Dengue, the excruciating mosquito-borne disease, is surging throughout the world and coming to places that had never had it. California just confirmed a rare U.S. case.Cases of dengue fever, a mosquito-borne viral illness that can be fatal, are surging around the world. The increase is occurring both in places that have long struggled with the disease and in areas where its spread was unheard-of until the last year or two, including France, Italy and Chad, in central Africa. Last week, health officials in Pasadena, Calif., reported a first case of locally transmitted dengue.What is dengue fever and why is it becoming more widespread?Dengue, a viral fever, is transmitted by Aedes species of mosquitoes. It can cause excruciating joint pain; is also known by the grim nickname “breakbone fever.” The Aedes aegypti mosquito, which has been driving many of the current outbreaks, is native to Africa, where it originally lived in forests and fed on animals. But decades ago it spread to the rest of the world via trade routes and adapted to thrive in urban areas, feeding on people and breeding in small bits of trapped water in places such as old tires, discarded bottle caps and trays used to catch air-conditioner drips. Now as more people move to urban areas — many to lower-quality housing in developing countries — they are more vulnerable to the virus. And climate change is bringing the mosquito to new places, where it is thriving. “Aedes mosquitoes thrive in warm and humid environments, so definitely climate change and rising temperatures and also extreme weather events are helping extend their habitat range,” said Dr. Gabriela Paz-Bailey, chief of the dengue branch at the division of vector-borne diseases at the U.S. National Center for Emerging and Zoonotic Infectious Diseases. How dangerous is it?Only one in four dengue cases are symptomatic. Some infections may produce only a mild flulike illness. But others can result in dreadful symptoms, including headache, vomiting, high fever and the aching joint pain. Full recovery can take weeks.About 5 percent of people who get sick will progress to what’s called severe dengue, which causes plasma, the protein-rich fluid component of blood, to leak out of blood vessels. Some patients may go into shock, causing organ failure.Severe dengue has a mortality rate of between 2 and 5 percent in people whose symptoms are treated. When left untreated, however, the mortality rate is 15 percent.Severe dengue may go untreated because patients live far from medical care or can’t afford it, or because hospitals are overwhelmed with cases during an outbreak.Or it can happen when dengue isn’t diagnosed in time because it’s appearing in a new area. That is a problem in resource-strapped countries such as Chad, of course, but also a challenge for a patient or clinician in Pasadena who is unfamiliar with dengue, Dr. Paz-Bailey said.Who is at risk?Demonstrators in Kolkata, India, last month protesting what they said were insufficient efforts to control a dengue outbreak.Dibyangshu Sarkar/Agence France-Presse — Getty ImagesForty percent of people globally live in areas where they are at risk of dengue infection; the disease is most common in tropical countries such as Brazil.The people most vulnerable to dengue live in housing that doesn’t keep mosquitoes away from them. In studies on communities along the U.S. southern border in areas where the aegypti mosquito is well established, researchers found that there were as many or sometimes even more of the mosquitoes on the Texas side, but far fewer dengue cases there than on the Mexican side.That is because more people on the U.S. side of the border had screened windows and air-conditioners, which limited their exposure to mosquitoes, and lived farther apart and were less social: By making fewer visits to friends and relatives, they were less likely to take the virus into new areas where a mosquito might pick it up from them and pass it on.It is unlikely that dengue will become a serious problem in the United States, “as long as people keeping living like they’re living now,” said Thomas W. Scott, a dengue epidemiologist and professor emeritus at University of California, Davis.Outside Puerto Rico and other territories where the disease is endemic, there are about 550 dengue cases each year in the United States, but they are imported by travelers who were infected abroad and passed the disease along to their close contacts.The case in Pasadena is a rare locally acquired case of dengue in the United States. City officials said on Friday that they had been trapping and testing mosquitoes in the neighborhood where the case was reported and had not found any further insects with the virus.But scientists say dengue will continue to spread to places that haven’t experienced it before.In addition to climate change, rising rates of urbanization around the world are playing a role, said Alex Perkins, who is an associate professor of biological sciences at the University of Notre Dame and an expert in the mathematical modeling of dengue transmission. If people have recently come from rural areas, they are unlikely to have priority immunity, so the virus can move swiftly through the population.“I don’t think that the case in Pasadena or anything else that I’ve seen lately is an indication of any looming crisis in the United States in the short term,” Dr. Perkins said. “But I think the general expectation that this is going to be a growing problem in the United States is reasonable.”Dr. Perkins said the experience of southern China offers a cautionary tale: Historically, the region saw only a handful of dengue cases each year. Then in 2014, there were 42,000 cases in Guangdong Province. “All of a sudden in one year, it grew by a couple of orders of magnitude without any real forewarning,” he said. He added, “In endemic settings, we’re continuing to have record years, year in and year out, and that’s what’s driving all these imported cases in the United States and elsewhere. And when it comes to the more marginal transmission settings such as the southern United States, southern Europe, China — it’s not getting better there either. So it’s really getting better nowhere: it’s all bad.”Is there treatment for dengue?There is at present no specific treatment for dengue infection, and patients are given only symptom management, such as medication to control pain. Drug companies have antivirals in clinical trials.Is there a vaccine?The effort to find a dengue vaccine has been long and complicated. Dengvaxia, a vaccine developed by the French firm Sanofi, was rolled out widely in countries such as the Philippines and Brazil starting in 2015, but two years later the company said it was causing vaccinated people who caught the virus to have more severe cases. The U.S. Centers for Disease Control and Prevention recommends use of Dengvaxia in endemic areas for people with a laboratory-confirmed previous dengue infection.The World Health Organization recently recommended a new vaccine called QDENGA, which can be used regardless of prior infection status, for children aged 6 to 16 living in areas with high dengue transmission. This vaccine has already been introduced in Indonesia, Brazil, Thailand and 16 European countries, including Britain and Italy, but it won’t be available in the U.S. any time soon. Takeda, the Japanese company that makes it, withdrew it from the F.D.A. approval process in July after a dispute over what data was being considered.Aedes aegypti cannot pass on the dengue virus when infected with the Wolbachia bacteria.Dado Galdieri for The New York TimesWhat else can we do?Some countries that have acted aggressively against dengue have controlled it. Singapore uses a combination of methods, including the inspection of homes and construction sites for breeding areas, with high fines for rules violations. “It’s a successful approach but they have a really large budget to support those activities, but not every country has that,” Dr. Paz-Bailey said.Brazil and Colombia have had success using a bacteria called Wolbachia: When Aedes aegypti is infected with the bacteria, it can no longer pass on the dengue virus. Projects there are mass-producing mosquitoes infected with Wolbachia, and releasing them to breed with wild insects in an effort to get the bacteria through the mosquito population.

Over the last two decades, medical facilities and staff have become casualties of war more frequently, in violation of international law.The explosion at the Ahli Arab Hospital in Gaza City on Tuesday was the latest in a growing series of violent incidents involving medical facilities in conflict zones, which together have taken an enormous toll on vital health care infrastructure and staff in violation of what was once a bedrock aspect of international law.Over last two decades, as the principle of sparing health care workers and facilities has continually eroded, the most dangerous incidents have been carried out by state actors, said Michiel Hofman, who is an operational coordinator for Doctors Without Borders in Sudan and a veteran of medical aid delivery in Afghanistan, Yemen and Syria.Yet Article 18 of the First Geneva Convention, ratified by United Nations member states after World War II, says that civilian hospitals “may in no circumstances be the object of attack, but shall at all times be respected and protected by the parties to the conflict.”Article 20 of the convention says that health care workers similarly must be protected by all sides.“The willingness of states to push the boundaries of international humanitarian law seems to have accelerated,” Mr. Hofman said. “It’s the states that have explicitly signed the Geneva Conventions, and states usually have far greater military power and especially air power.”The two sides traded blame for the explosion at the hospital in Gaza City.Mohammed Saber/EPA, via ShutterstockIn Ukraine, Russia has carried out more than 1,100 attacks on health care facilities and personnel since it began its invasion 21 months ago, a staggering number for so short a period, said Leonard Rubenstein, an expert in health and human rights at Johns Hopkins University.Mr. Rubenstein chairs the Safeguarding Health in Conflict Coalition, which is made up of more than three dozen human rights and humanitarian organizations working in conflict zones, tracking attacks on health care around the world.Mr. Rubenstein said the pattern of Russian attacks showed that Moscow has in some cases intentionally targeted hospitals and in others indiscriminately attacked areas where hospitals were located; both are war crimes. “They’re unaccountable, with complete impunity,” he said. “And they don’t care.”Neither Russian soldiers or commanders nor any other state or paramilitary actor that has attacked medical sites, with one exception, has ever faced prosecution by international bodies, he added: “There is wide agreement in the international community that attacks on health care are unacceptable — protection of health care is like motherhood and apple pie. But there’s no real commitment by governments to do what you need to do to stop it.”He added: “There has been no accountability, instead complete impunity — no prosecution and political interference with U.N. entities that seek even mild condemnation of states responsible for attacks.”The only time a deliberate attack on a hospital was ever referred for prosecution in an international court involved the war in Bosnia. The charge was one of seven against a Serbian military commander considered by the tribunal investigating war crimes in the former Yugoslavia.The International Criminal Court, a tribunal set up by the United Nations 21 years ago to prosecute crimes against humanity, has never issued an indictment for an attack on medical personnel or infrastructure.A strike in March 2022 hit a maternity hospital in Ukraine.Evgeniy Maloletka/Associated PressAttacks on medical facilities jeopardize health care not only for those injured by fighting, but also for all those with routine medical needs. On Thursday, Doctors Without Borders (also known as M.S.F., an abbreviation for its French name, Médecins Sans Frontières) withdrew a surgical team from a hospital in Sudan after military authorities blocked all delivery of supplies to the facility. The team had been providing lifesaving trauma surgeries and cesarean sections from one of the last functioning hospitals in the capital, Khartoum.“It’s so painful, because of the moral distress of the medics,” Mr. Hofman said. They were unable to function without basic supplies, but also profoundly disturbed to cut off one of the last sources of care in a city where fighting has not let up since rival factions of the military government went to war in April.In Ukraine, Russian attacks have destroyed 10 to 15 percent of medical facilities. The damage is even more far-reaching than it might seem, said Pavlo Kovtoniuk, a former deputy minister of health in Ukraine who now works with a think tank called the Ukrainian Health Center.“Hospitals symbolize respect for civilian life, and when people see that disregarded they say, ‘We have to get out,’” he said. “We have a huge loss of human capital, with more than six million people now living outside the borders.”Among those who remain, there is a growing population in need of rehabilitation and psychosocial support, from a steadily shrinking health system.“This is not a situation of waging war according to the laws of war and the Geneva Convention — this is a completely different philosophy of war where civilian lives are disregarded entirely,” Mr. Kovtoniuk said.He added: “We are revisiting the rules we thought were a given on regard for civilian life, and Russia has contributed to this feeling, ‘OK, we can do this. We can attack civilian infrastructure as a weapon of war.’”Ukrainian officials are working with the International Criminal Court to compile evidence from the attacks, Mr. Kovtoniuk said. At least some top Russian officials must be indicted in order to re-establish the principle of protecting health care workers and facilities, he said. Russia has often either said that the facilities it hit were harboring Ukrainian fighters or dismissed the accusations as fake.In Sudan, M.S.F. says that fatalities caused by neglected medical needs are as great as those caused by violent injuries. According to the World Health Organization, 70 percent of Sudan’s medical facilities are no longer functioning. More than seven million people are now internally displaced and face a cascade of disease outbreaks.The World Health Organization says vaccine delivery is impossible in much of Sudan.Agence France-Presse, via Getty ImagesThere are epidemics of cholera, malaria, dengue fever and measles in Sudan. The W.H.O. says measles and malnutrition have killed 1,200 children since the war began in April, and vaccine delivery is impossible in many parts of the country.“Health care was terrible to begin with, and any specialized care we had was overwhelmingly centered in Khartoum and it’s no longer functioning,” said Dr. Yasir Yousif Elamin, president of the Sudanese American Physicians Association. “The places able to do cardiac surgery, neurosurgery, cancer care, dialysis — all of these are out of service now.”People who need these services are scattering to areas far from the capital; patients who need dialysis three times a week are receiving it once in a 10-day stretch, while cancer patients might manage to find chemotherapy treatment every few months, he said.The physicians’ association is tracking attacks on health care facilities in hopes of supporting eventual prosecution.Last month, in the city of Wad Madani, Dr. Elamin met a 5-year-old child who had been shot in the abdomen in Khartoum. His mother had taken him hundreds of miles in search of help.“Imagine you don’t have something as basic as this, for a boy hit accidentally,” Dr. Elamin said.Researchers began tracking attacks on health care facilities in conflict zones in an organized fashion only in the early 2000s, so it is difficult to speak with much certainty about the trend, Mr. Rubenstein said.But in an analysis of the figures for 2022, Safeguarding Health in Conflict said that the 1,989 incidents that were tabulated represented “by far the highest number” documented since the coalition began reporting a decade ago.After Ukraine, which accounted for nearly half the incidents, the most-affected country was Myanmar. More than 800 health care workers have been arrested there since a military coup in 2021.Between 2014 and 2016, there was a series of horrific bombings of medical facilities in Afghanistan, Syria and Yemen — including a U.S. airstrike on an M.S.F.-run trauma center in Kunduz, Afghanistan, in 2015 that killed 42 people. (The Pentagon called it “unintentional.”)The aftermath of a United States airstrike on the Doctors Without Borders hospital in Kunduz, Afghanistan, which killed 42 people.Victor J. Blue for The New York TimesThe violence prompted the U.N. Security Council to unanimously adopt a resolution calling for greater protection of health care workers and facilities in armed conflict, which brought “a bit of a breather,” Mr. Hofman said. Those kinds of airstrikes continued in Syria, however.“But now with four major wars erupting in the last few years — Ethiopia, then Ukraine, Sudan, and now Gaza — we are at a peak again,” he said.There have been more than 115 attacks on health care facilities and personnel in the West Bank and Gaza Strip since the Oct. 7 Hamas attacks. Israel has warned 20 hospitals in the north of Gaza to evacuate their patients in anticipation of a ground invasion but Palestinian doctors say it is impossible to move them.In 2009, a suicide bomber infiltrated a graduation ceremony for medical students in Mogadishu, the Somali capital, and killed three cabinet ministers who were in attendance, plus the dean of the medical school, a dozen students and two journalists.In addition to the terrible loss of life, the International Committee of the Red Cross calculated that an indirect effect of those deaths was as many as 150,000 missed physician consultations per year, in a country where the medical system was already in tatters because of a decades-long civil war.

An esteemed pediatrician, he overcame apartheid’s barriers to help make his country a global leader in H.I.V. care and research.Hoosen Coovadia, a pediatrician who used science to fight for racial justice in apartheid South Africa and later transformed the approach to H.I.V. treatment for pregnant women in Africa and beyond, died on Oct. 4 at his home in Durban. He was 83.His daughter, Anuschka Coovadia, a physician in South Africa, confirmed the death, saying he had been in poor health for two years and was further debilitated by a case of Covid-19 several months ago that kept him in intensive care for weeks.Dr. Jerry Coovadia, as he was familiarly known, was a leader in the struggle against white rule in South Africa and campaigned for decades for the political transition that brought the African National Congress to power in 1994.But when, four years later, President Thabo Mbeki began to deny that the human immunodeficiency virus caused AIDS, and asserted that new treatments for H.I.V. were poisons he would not permit to be given to South Africans, Dr. Coovadia became one of the government’s fiercest critics.“Never was a doctor so vilified as Jerry Coovadia in the A.N.C. for his implacable and quietly militant stand against Thabo Mbeki,” said Zackie Achmat, the founder of the Treatment Action Campaign, a movement of people living with H.I.V. that also battled Mr. Mbeki, who was unseated in a party putsch in 2008.Dr. Coovadia and the activists he supported eventually won that fight, and he helped make South Africa a global leader in H.I.V. care and research. He also mended some relationships with the government, although he remained a vocal critic of inequity in the post-apartheid years.In a statement after Dr. Coovadia’s death, President Cyril Ramaphosa of South Africa said, “Our nation’s loss will be felt globally, but we can take pride at and comfort from the emergence of a giant of science and an icon of compassion and resilience from our country.”Hoosen Mahomed Coovadia was born on Aug. 2, 1940, in Durban. His parents, Mohamed Coovadia and Khateja Moosa, came from prosperous merchant families in Durban’s Indian community, though his father, a compulsive gambler, lost most of his wealth while Dr. Coovadia was still young.He was admitted to the University of Natal medical college, set up by the apartheid government for Black and so-called colored students like Dr. Coovadia, but after a short time he concluded that the education it offered was inferior. He applied to study in Cape Town, but the government denied him the permit to travel that he required as a nonwhite student.Instead, he traveled to India and enrolled at Grant Medical College in Bombay (now Mumbai). There he was exposed to anticolonial ideas and met other South African students, with whom he organized a political association. Prominent leaders of the anti-apartheid movement visiting India would address them.Dr. Coovadia, with a medical degree from Grant, returned to South Africa in 1966. Three years later, he married Zubeida Hamed, who had also graduated from Grant and was finishing her training in dermatology. Dr. Hamed shared her new husband’s growing interest in activism, and their home, in Durban, became a mecca for political meetings. Dr. Coovadia went to work as a pediatrician at King Edward VIII Hospital in Durban, an institution that could treat only nonwhite South Africans under apartheid, and later joined the department of pediatrics at the University of Natal Medical School (now part of the University of KwaZulu-Natal). He came under suspicion by the regime for conducting research on topics such as racial disparities in infant mortality in South Africa. He also joined the Natal Indian Congress, an anti-apartheid organization, and soon became a leader of it.In 1975, Dr. Coovadia earned a master’s degree in immunology from the University of Birmingham in Britain. Returning to South Africa, he found opposition to apartheid there swelling into open revolt. He helped found the United Democratic Front, a coalition of more than 400 trade unions, religious organizations and other civic groups opposed to white rule. In 1989, the police raided and ransacked his home in search of papers related to secret talks between the regime and the A.N.C.Dr. Coovadia in 1989 as a leader of the Natal Indian Congress, an anti-apartheid organization. He and another group member, Paddy Kearney, displayed a list of 189 people arrested for political activities. 1860 Heritage CentreA month later, South African secret police planted a bomb in front of Dr. Coovadia’s home. His son, Imraan, a novelist and professor of creative writing at the University of Cape Town, said his father had become such a prominent critic of apartheid abroad, speaking at scientific meetings, that the regime had decided to eliminate him. The bomb destroyed the second floor of the house, but the family survived.“It took weeks to get the walls rebuilt,” his daughter, Anuschka, said, “and during that time, my father’s medical students came on a schedule, protecting the house with broom poles and sticks, sitting out all night. There was so much love from his community of students.”In addition to his son and daughter, he is survived by his wife and five grandchildren.Dr. Coovadia wrote a textbook on child health now in its seventh edition, mentored dozens of students and researchers, many of whom became health ministers and key figures in global health, and conducted pioneering work on measles and pediatric kidney disorders. He advised successive South African governments from various positions, including a seat on the powerful National Planning Commission; led international research projects; published widely in scientific journals; and received awards, including the Star of South Africa, the country’s highest honor, presented by President Nelson Mandela.But it was his work on H.I.V. that had perhaps the greatest impact on global policy, and which drew him into an unexpectedly vicious political battle.In the late 1980s, he started to see babies with H.I.V. arriving at the hospital, prompting him to begin researching ways to stop the transmission of the virus from mothers to their children. “He considered it another form of oppression for these women, who were Black, who were poor, who were often rural — and on top of all of that, had H.I.V.,” said Salim Abdool Karim, a leading authority on H.I.V. globally and a former student of Dr. Coovadia’s.By the 1990s, the World Health Organization was recommending that women with H.I.V. feed their children with baby formula rather than breast milk, which could transmit the virus. But Dr. Coovadia suspected — and then proved in a series of studies — that the risk was minimal in exclusively breastfed infants, and that the health benefits for infants whose mothers did not have access to clean water with which to mix formula far outweighed the risk from H.I.V.Dr. Coovadia battled the W.H.O. and succeeded in having the policy reversed. He also helped demonstrate that giving antiretroviral drugs to pregnant women could prevent them from transmitting the virus to babies at birth.South Africa had the world’s largest number of people living with the virus by the late 1990s, but when President Mbeki, to whom Dr. Coovadia had earlier been close, created a commission to govern the AIDS response, he stacked it with rogue researchers and self-proclaimed experts known as “AIDS denialists.” Manto Tshabalala-Msimang, a health minister appointed by Mr. Mbeki, told people living with H.I.V. that they could stave off AIDS by eating garlic and beets. Dr. Coovadia was incensed.In 2000, as he prepared to become a co-chair of a major global AIDS conference in Durban, the A.N.C. government put immense pressure on him to present the denialist view.“He was such a courageous and principled person: He would not give in,” said Dr. Peter Piot, who was then the head of the United Nations AIDS agency and who joined Dr. Coovadia in “turbulent” meetings with government officials ahead of the event.President Mbeki, as head of state, opened the conference and, to the horror of much of the audience, reiterated his denialist view. The government then demanded that Dr. Coovadia allow Dr. Tshabalala-Msimang to close the event.Dr. Coovadia’s daughter recalled that 10 “thuggish” men came to the family’s hotel room the night before the conference ended and ordered him to a meeting with the minister. “When he came back, he was utterly shaken,” she said. “He didn’t sleep that night.”Knowing it might mean both the end of his professional life and ostracism from the party for which he had fought for decades, Dr. Coovadia nevertheless refused the minister the platform. Instead, the keynote speaker at the final session was Mr. Mandela, who had stepped down as president a few years earlier. He exhorted the world to bring AIDS treatment to his country and the rest of Africa.After Mr. Mbeki left office, Dr. Coovida helped South Africa roll out what became the world’s largest H.I.V.- treatment programs.

We need new ways to fight mosquitoes. Dangerous species are spreading to new parts of the world, bringing diseases like malaria and dengue with them. Our old weapons, such as bed nets and insecticides, don’t work well anymore: Mosquitoes have evolved to resist and evade them.

The repellents can last for a year and researchers hope they will be sold for just a few dollars each — about the same price as a bed net — so that families in low-income countries can buy them.

Next, for outdoors: A gizmo with the clunky name of Attractive Targeted Sugar Bait, or ATSB, is a flat packet about the size of a sheet of looseleaf paper that is filled with pouches of a sugary liquid laced with a new kind of insecticide. The bait is sealed under a membrane thin enough for a mosquito to drink through.

Every mosquito, male or female, needs to feed on sugar. ATSBs lures them with fruit syrup, then poisons them. ATSBs are hung about six feet off the ground (out of range of children and goats) on the outside of people’s homes and in places where they gather outdoors.

For both inside and outside, there’s another novel experiment, which makes use of ivermectin, a drug lots of people have heard of. Ivermectin is an endectocide, a medicine usually taken to kill parasites such as head lice. But there is evidence that it may also kill mosquitoes that bite humans who were recently treated with it.

The researchers are waiting for data to see how much this drove down malaria. It’s helpful that people are already familiar with ivermectin, which is safe and cheap (although with delivery, this method costs about $2.75 per person per year). As a bonus, ivermectin significantly reduces cases of scabies, head lice and worms.

The decision has little practical effect but is a significant moment in the struggle against a virus that has killed millions and upended lives throughout the world.The World Health Organization announced on Friday that it was ending the emergency it declared for Covid-19 more than three years ago, a milestone in the fitful emergence from a pandemic that has killed millions of people around the world and upended daily life in previously unimaginable ways.“With great hope, I declare Covid-19 over as a global health emergency,” said the W.H.O. director general, Dr. Tedros Adhanom Ghebreyesus.In practical terms, the decision changes little: Many countries have already ended their states of emergency for Covid, and have moved away from almost all public health restrictions implemented to control the virus. The United States will lift its Covid emergency on May 11. The virus will continue to have pandemic status according to the W.H.O., much as H.I.V. does.But the lifting of the W.H.O. designation — officially called a “public health emergency of international concern” — is a significant moment in the evolving human relationship with the novel coronavirus.Dr. K. Srinath Reddy, who led India’s Public Health Foundation through the pandemic, said the decision to lift the emergency was appropriate, because of the high levels globally of immunity to Covid, induced by vaccination or infection, or both.“It no longer possesses the same level of danger,” he said, adding that Covid “has achieved a level of equilibrium, a certain type of coexistence with the human host.”Dr. Reddy said the end of the emergency status should also be appreciated as a moment of human achievement and a “celebration of science.”“It’s important to recognize that what made the virus change its character is not only evolutionary biology,” he said, “but also the fact that we have induced it to actually become less virulent, by vaccination, by masks, by a number of public health measures.”Globally, there have been 765,222,932 confirmed cases of Covid, including 6,921,614 deaths, reported to the W.H.O. as of May 3. But these figures are a vast undercount of the pandemic’s true toll. Independent researchers have estimated the real death tally of the virus to be many times higher.A year ago the W.H.O. said that 15 million more people had died in the first two years of the pandemic than would have in normal times, a figure that laid bare how vastly countries had undercounted victims. In Egypt, excess deaths were roughly 12 times as great as the official Covid toll; in Pakistan, the figure was eight times as high. Developing nations bore the brunt of the devastation, with nearly eight million more people than expected dying in lower-middle-income nations by the end of 2021.And Covid continues to spread: The W.H.O. recorded 2.8 million new cases globally, and more than 17,000 deaths, from April 3 to 30, the most recent numbers available. As many countries have reduced their testing for Covid, these numbers also probably represent a significant undercount.The W.H.O.’s emergency declaration was a crucial piece of guidance when it was made on Jan. 30, 2020, when just 213 people were known to have died of the virus. It signaled to the world that this new virus posed a threat outside of China, where it emerged, and gave countries critical buttressing to impose potentially unpopular or disruptive public health measures.The virus that jumped into humans in late 2019 proved to be an unpredictable adversary, mutating swiftly and significantly in ways that allowed it to resurge and devastate countries just as they thought the worst was past. A brutal wave of the Delta variant ravaged India just weeks after Prime Minister Narendra Modi bragged about how well the country had done in its Covid response. The Omicron variant, while less virulent, spread with a deceptive ease that made it the fourth-leading cause of death in the United States in 2022, and a major killer in many other countries.The first large-scale vaccinations began on Dec. 8, 2020, less than a year after the first case of the disease was reported to the W.H.O., an extraordinary triumph of science. But the collaborative process of vaccine development was followed by a grim period of hoarding and nationalism; a full year later, when people in industrialized countries were receiving second and third doses of the vaccine, just five percent of people in sub-Saharan Africa had been vaccinated.Dr. Githinji Gitahi, executive director of Amref Health Africa, said it was time to lift the emergency. “The danger of keeping it forever is diluting the tool — you need it to retain its force,” he said. The declaration helped to mobilize resources for Africa, he said, but did nothing to counter the bleak experience of what he called “vaccine injustice.” Amref continues to work on supporting vaccination in 35 African countries; continent-wide, coverage now stands at 52 percent.The pandemic also has a positive legacy, Dr. Gitahi said, because it spurred the highest level of cooperation ever seen among African countries, including the creation of an African Union task force to coordinate procurement of vaccines.The W.H.O. decision was not welcomed by all health experts. Dr. Margareth Dalcolmo, a respiratory physician and member of Brazil’s National Academy of Medicine who was one of that country’s most prominent experts guiding the public through Covid, said it was too soon to lift the emergency, given that there are still urgent tasks such as research into Covid variants and development of better vaccines. Having the designation of global public health emergency also creates leverage for lower-income nations to access treatments and support, she said.On May 3, the W.H.O. issued an updated Covid management plan, which it said was intended to guide countries on how to manage Covid over the next two years as they transition from emergency response to long-term Covid prevention and control.Opening a meeting of W.H.O. experts in Geneva on Thursday, Dr. Ghebreysus told the committee that for each of the past 10 weeks, the number of weekly reported Covid deaths had been the lowest since March 2020. As a consequence, life has returned to normal in most countries and health systems are rebuilding, he said.“At the same time, some critical uncertainties about the evolution of the virus persist, which make it difficult to predict future transmission dynamics or seasonality,” he said. “Surveillance and genetic sequencing have declined significantly around the world, making it more difficult to track known variants and detect new ones.”And access to lifesaving Covid treatments continues to be sharply unequal globally, he said.Dr. Dalcolmo said the lifting of the global emergency should be viewed not as a milestone, but as a warning. “Take this as an alert, a time to start being prepared for the next pandemic,” she said, “because we know respiratory viruses are going to increase.”

Leaders on the continent have vowed that if there is another pandemic, they won’t be shut out of the vaccine market.Just 3 percent of all Covid-19 vaccine doses delivered in 2021 went to Africa, home to a fifth of the world’s population, according to the World Health Organization. In the vast debacle of global vaccine inequity, it was Africa that was left furthest behind as the pandemic raged, and that had the least leverage to negotiate contracts.African leaders vowed to make sure that never happened again. High-income nations and philanthropic groups promised to help fund the effort to make vaccine access more equitable. There was a flurry of announcements of new partnerships and investments: plans to modernize the handful of existing pharmaceutical manufacturing operations in Africa; plans to build new ones; plans to send shipping containers from Europe with pop-up facilities to produce the new mRNA vaccines; plans for an mRNA production incubator that would dispense open-source technology around the continent.Now, some of the hype has subsided, and there are some signs of real progress. But it’s also become evident just how big the hurdles are.There aren’t many shortcuts in the decades-long process of developing a sophisticated biotechnology industry that can make a routine vaccine for export, let alone develop a shot to protect against a new pathogen.The African Union has set a goal of having 60 percent of all vaccines used on the continent produced in African nations by 2040 — up from 1 percent now — an plan that looks wildly ambitious given the current production landscape.The big issue, as always, is money. The many-step process of making vaccines needs high biosecurity and intense quality control. The expense of putting it all in place means that vaccines made in Africa are going to cost significantly more than those from the Indian pharmaceutical industry, which is the major supplier of routine vaccines used in Africa.Manufacturers such as the Serum Institute of India, the world’s largest vaccine maker, have achieved huge economies of scale and have taken over much of the market share that was held by European producers. But the Covid vaccine rollout made clear that despite the low price of Indian-made vaccines, African leaders cannot afford to rely on them. In March 2021, when millions of Serum-made doses of the AstraZeneca vaccine were bound for Africa, the Indian government imposed an export ban and rerouted those vaccines to its own population.The Africa Centers for Disease Control and Prevention says the continent’s existing vaccine market is worth an estimated $1.3 billion and is expected to grow to about $2.4 billion by 2030. But many who work in global health say buyers will have to pay a “resilience premium” — a higher price for African-made vaccines, the production of which helps build up the African industry. There is a lot less clarity about who is going to be willing to pay that higher price.The obvious candidate is Gavi, the organization that uses funds donated by high-income countries and major philanthropies to purchase routine and emergency vaccines for low- and middle-income countries. Gavi buys half the vaccines used in Africa today.Aurélia Nguyen, Gavi’s chief program strategy officer, says the organization is ready to sign advance purchase contracts with new vaccine makers in developing countries, to assure business owners of an income stream that will defray investments in expansion.“The traditional market economics that got us to a place where we have strong developing-country manufacturers in Asia and Latin America are not going to get us to a place where we’re going to have regional players in the African continent,” she said. “Gavi is in a position to bridge the market failure.”A vial of Johnson & Johnson’s Covid vaccine in Juba, South Sudan.Lynsey Addario for The New York TimesIf Gavi is able to provide that cushion, these are the projects that experts say are most likely to help the continent reach the goal of producing a majority of vaccines for Africans in Africa. Most will need at least three years before they have even a bottling-and-packaging line running.In SenegalThe Pasteur Institute of Dakar was making a million doses a year of yellow fever vaccine before Covid, and its business was flagging. But it has recently been a major target for new investment and has nearly completed a large expansion of its existing production plant. It is aiming to increase its production of yellow fever vaccine to 50 million doses a year. A second site will produce a low-cost rubella and measles vaccine for the African market, with a production target of 300 million doses.It will use a new bio-manufacturing production platform from Univercells, a Belgian start-up that aims to make vaccine ingredients more quickly and in a smaller space.“The progress in Dakar is the fastest I’ve seen anywhere in the world,” said Prashant Yadav, a medical supply chain expert at the Center for Global Development who visited the institute several times over the past year.In South AfricaAspen Pharmacare, one of the few serious pharmaceutical players in Africa before Covid, received an infusion of $30 million in philanthropic funds to build up a production process for four of the main childhood vaccines, including shots for pneumonia and rotavirus.In 2021, the World Health Organization set up an “mRNA production hub” at a small biotechnology company in Cape Town called Afrigen Biologics and Vaccines, with the goal of reverse-engineering the Moderna Covid vaccine and then sharing mRNA production knowledge across the global south. Afrigen will put its Covid shot into clinical trials in early 2024. There is no longer a market for Covid vaccines, but the hope is that the process of designing, testing and producing this product will build up technological know-how to make others including an mRNA shot for tuberculosis, an Afrigen priority.Afrigen’s production partner is the nearby BioVac Institute, which makes childhood vaccines for South Africa. BioVac signed a deal to bottle Pfizer’s Covid vaccine (a process called fill-finish), and has a new licensing and technology transfer deal to produce an oral cholera vaccine with the International Vaccine Institute, a South Korean nonprofit.In RwandaSix shipping containers arrived in the country in mid-March to form the first “BioNTainer, — a pop-up mRNA vaccine manufacturing line packaged in the containers — donated by BioNTech, the maker of the mRNA technology in Pfizer’s Covid vaccine. The modular site is intended to form the core of a new vaccine manufacturing center. It will be staffed by Europeans for the first five years, according to BioNTech.A key challenge here, Dr. Yadav noted, is that the site has no vaccine to make: There is no demand for the Covid vaccine, and BioNTech does not currently make any other product. A malaria or tuberculosis mRNA vaccine that could be useful for Rwanda and the region is most likely a decade away. The new capacity in the country is only for production; in Rwanda, as in most other African countries, there is no biotech industry capable of the kind of research and development that is essential when responding to a new pathogen, said Alain Alsalhani, a vaccines expert with Doctors Without Borders’ access-to-medicines campaign.And beyondTwo more companies — Biogeneric Pharma in Egypt, which will receive an mRNA technology transfer from Afrigen, and SENSYO Pharmatech in Morocco — have received significant investment to expand their production. And in Kenya, the government is having the Kenya BioVax Institute switch from producing animal vaccines to making human ones. It has tapped Dr. Michael Lusiola, an expatriate Kenyan who was a senior executive with AstraZeneca in the United Kingdom, to come home and run it.Ms. Nguyen said that having the ability to manufacture large numbers of vaccines would help to give Africa security in the event of another pandemic. The continent could build that capacity while making routine vaccines for the African market, she said.Research at the Pasteur Institute of Dakar.Seyllou/Agence France-Presse — Getty ImagesIn most cases, that will mean starting with fill-finish agreements for existing vaccines — putting a bulk vaccine made somewhere else into vials. Then companies can begin manufacturing the actual drug substance and, eventually, conduct the research and develop the vaccines, either for known pathogens or for new ones.Countries will need stronger regulatory agencies so their vaccines can be quickly approved for export. They will also need better supply chains of everything that goes into vaccines. The Africa C.D.C. hopes to create regional ones, in which some countries makes glass vials and others make drug substances, as a way to ensure equitable access in a future pandemic.Ms. Nguyen said she was encouraged by the number of African initiatives that were embracing new technologies that would allow them to “leapfrog.” In the past, making vaccines required a huge physical footprint, so that meant producing huge volumes to pay for it.“Having a small unit that can get up and running and do five or 10 million doses and then switch to something else — I think that really changes the established marketplace,” she said.Many of the new initiatives are heavily dependent on philanthropic funding, much of it from the Bill & Melinda Gates Foundation and the multilateral Coalition for Epidemic Preparedness Innovations, as well as low-cost bilateral loans. It’s not clear how long that enthusiasm will last. Martin Friede, who leads the vaccine research unit at the W.H.O., predicted “the Covid guilt will be over by this afternoon.” He added, “I just don’t see South Africa agreeing to buy vaccines from Nigeria at a higher price than vaccines from India or Europe — that’s a tough ask.”Patrick Tippoo, the head scientist at Biovac in Cape Town and a key player in the African network of manufacturers, said that was similar to what he and his colleagues were hearing in meetings. “There’s a lot of good will from development financing institutions,” he said, but concern about how manufacturers can repay loans. “That’s reliant on product volumes and access to markets,” he continued. “So we kind of go around in circles a little bit.”BioVac’s new cholera vaccine is a prime example of the promise of this new manufacturing capacity, and the obstacles it faces. There is a critical global shortage of that vaccine, and outbreaks are raging in several sub-Saharan countries. This will be the first time in decades that an African drugmaker will be developing a strategic vaccine, taking it through the full chain of clinical development and into manufacturing, regulatory authorization and, BioVac hopes, prequalification by the W.H.O. for global use. But it will be a many-year process — and will require construction of costly new facilities.“A number of things have advanced, and if half of them succeed we will be doing well,” Mr. Tippoo said. “It will take us closer — the question is, Will it take us close enough?”

The spread of the Ebola-like virus has claimed lives but could be a crucial chance to test a vaccine — if supplies and researchers are mobilized in time.Two concurrent outbreaks of the Marburg virus, a close cousin of Ebola that can kill as many as 90 percent of the people it infects, are raising critical questions about the behavior of this mysterious bat-borne pathogen and global efforts to prepare for potential pandemics.Marburg, a hemorrhagic fever, is rare: Just a handful of outbreaks have been reported since the virus was identified in 1967. But a steady uptick in occurrences in Africa in recent years is raising alarm.Marburg causes high fever, vomiting, diarrhea and, in the most severe cases, bleeding from orifices. It spreads between people via direct contact with the blood or other bodily fluids of infected people and with surfaces and materials such as clothing contaminated with these fluids. One of the two outbreaks, in Tanzania in East Africa, seems to have been brought under control, with just two people left in quarantine. But in the other, in Equatorial Guinea on the west coast, spread of the virus is ongoing, and the World Health Organization said last week that the country was not being transparent in reporting cases.There are no treatments or vaccines for Marburg, but there are some candidates that have shown promise in Phase 1 clinical trials. However these candidates must be tested in active outbreaks to prove they work, and so far, no vaccine supplies have been delivered to test in the current outbreaks.“The moment an outbreak is detected there should be a mechanism of moving in quickly,” said Dr. John Amuasi, the head of the global health department at Kwame Nkrumah University of Science and Technology in Ghana who investigated a Marburg outbreak in that country last year.The W.H.O. and others are good at rapid response to control the spread of a virus, he said, but lack a similarly swift response for research. It requires ready-to-ship stockpiles of the vaccine candidates and researchers equipped to operate without putting additional strain on an already struggling health system; neither currently exists. The W.H.O. says it has drafted a research protocol that can be applied in these outbreaks and to any other filovirus — the family that includes Marburg and Ebola — and it has been scrambling for more than a month to get trials underway, working against a ticking clock.If outbreak response works well — isolating cases and tracing contacts — the epidemic will quickly be controlled, which seems to be the case in Tanzania. If the response doesn’t go as well (as in Equatorial Guinea), there are fears of a widespread outbreak and a redoubled need for vaccination.When an Ebola outbreak began in Uganda in September 2022, the strain that rapidly claimed lives was one for which there was no vaccine, but, similarly, there was a strong candidate waiting a chance to be tested. Researchers announced plans to try it in Uganda. But the outbreak was over by the time the vaccine doses arrived.The outbreaks in Equatorial Guinea and Tanzania are the first ever reported in either country. The outbreak in Equatorial Guinea began in January. The government has reported the deaths of nine people with confirmed Marburg virus disease and the deaths of another 20 people linked to the confirmed cases who were not tested but are considered probable cases.The government of Equatorial Guinea has released limited information about the outbreak, and the W.H.O. has said there are likely undetected chains of transmission and that not all the known cases have a clear connection to each other, suggesting a wider spread than previously thought.“W.H.O. is aware of additional cases, and we have asked the government to report these cases officially to W.H.O.,” Dr. Tedros Adhanom Ghebreyesus, the agency’s director, said last week.The outbreak in Tanzania was first reported in March. Five people with confirmed Marburg infections have died there, including a health care worker.No new cases have been reported in Tanzania for two weeks but the Marburg incubation period is 21 days, so the outbreak is considered active.“This is the hard part, with people in isolation, waiting through the days,” said Kheri Issa, the Tanzania Red Cross manager for Marburg viral disease response, in a telephone interview from the Kagera area where the disease broke out.The W.H.O. said both outbreaks pose regional risks: Equatorial Guinea has porous borders with Cameroon and Gabon, and so far the cases have appeared in geographically diffuse parts of the country. In Tanzania, the Kagera region has busy borders with Uganda, Rwanda and Burundi.These outbreaks follow one in Ghana last year and in Guinea the year before — a marked shift from the sporadic occurrences in previous years. Dr. Amuasi said better tracking was likely contributing to what appeared to be a rise in cases. As part of the response to the Covid-19 pandemic, he said, every African country improved its PCR testing capacity and infectious disease surveillance, which means Marburg is being diagnosed more frequently.But that suggests there may have historically been more of the virus circulating among humans than has been thought, Dr. Amuasi said, and the way it sickens people may be different than has been understood.Dr. Nancy Sullivan, the director of the National Emerging Infectious Diseases Laboratories at Boston University, said she believes climate change, and the way it is shifting human and animal behavior, is driving an actual increase in cases. “We’re impinging much more on reservoirs” of the virus, she said.Dr. Sullivan designed the Marburg vaccine candidate farthest along in development when she worked with the National Institute of Allergy and Infectious Diseases. It showed safety and immune response in a Phase 1 clinical trial, and the Sabin Vaccine Institute, a nonprofit organization based in Washington that promotes global vaccine development, is continuing the testing process.The Sabin Institute said it has 600 doses of the vaccines in vials and ready to use and plans for an eventual stockpile of 8,000 by the end of this year. Dr. Sullivan said 600 doses would be enough to start a ring vaccination trial of those at risk in Tanzania and Equatorial Guinea.But the W.H.O. has yet to announce operational details for a trial of this or three other vaccine candidates. Transporting the doses into the country is just one challenge; a trial would require a principal investigator from the outbreak country, legal agreements with the vaccine makers and regulatory approval. Equatorial Guinea has a notoriously opaque government that has been under the control of President Teodoro Obiang Nguema Mbasogo and his family for more than 30 years.Without committed resources and preapproved trial protocols, filovirus outbreaks will keep happening with little progress on interventions that could stop them, Dr. Amuasi said.

Incidence of illnesses such as diabetes and hypertension are climbing quickly in most sub-Saharan countries, but the conditions are rarely diagnosed or treated.NAIROBI, Kenya — Hannah Wanjiru was plagued by dizzy spells and headaches for years. After a half-dozen costly trips to the doctor, she was finally diagnosed with high blood pressure. It took two more years — and some fainting spells — before she finally started to take medication. By then, her husband, David Kimani, had been shuttling between doctors himself and ended up with a diagnosis of diabetes, another condition the couple knew nothing about.They might have wished for different diseases. Not far from their small apartment in the Kenyan capital, there is a public hospital where treatments for H.I.V. and tuberculosis are provided for free. Posters for free H.I.V. prevention services paper the streets in their low-income neighborhood.There is no such program for high blood pressure or diabetes, or for cancer or chronic respiratory conditions. The health systems in Kenya and much of sub-Saharan Africa — and the international donations that support them — are heavily weighted to the treatment of infectious diseases such as H.I.V. and malaria.“Sometimes I go to have my sugars tested and I wait all day and I am almost fainting right there in the lineup,” said Mr. Kimani.Success in fighting H.I.V., malaria and other deadly infectious diseases, plus an expansion of essential services, have helped countries in sub-Saharan Africa achieve extraordinary gains in healthy life expectancy over the past two decades — 10 additional years, the largest improvement in the world, the World Health Organization reported recently.“But this was offset by the dramatic rise in hypertension, diabetes and other noncommunicable diseases and the lack of health services targeting these diseases,” the agency said, launching a report on health care in Africa. It warned that the rise in life expectancy could be erased before the next decade is out.Noncommunicable diseases now account for half of hospital bed occupancy in Kenya and more than a third of deaths. The rates are similar across the rest of sub-Saharan Africa, and people in this region are being affected at younger ages than those in other parts of the world.Mr. Kimani and Hannah Wanjiru on the roof of their home. There is a clinic nearby that offers free treatment for H.I.V. and tuberculosis, but there is no such program for conditions like diabetes or cancer.Malin Fezehai for The New York Times“Vaccination programs are running very well, H.I.V. programs are running very well — but these same people will die of noncommunicable diseases while they are young,” said Dr. Gershim Asiki, a research scientist focused on management and prevention of these conditions at the African Population and Health Research Center, an independent organization in Nairobi.The medications and supplies Ms. Wanjiru, 44, and Mr. Kimani, 49, need to control their conditions cost $60 each month, a huge portion of the income from their small convenience store, Ms. Wanjiru said over tea in their sitting room. Both skip their medication on months when school fees are due for their four children.“I get headaches and I feel weak, and then I feel stressed knowing I need to buy medication instead of food for my family,” Mr. Kimani said.Routine screening for conditions such as high blood pressure is rare here, diagnosis rates are low and care is often available only at specialized centers in urban areas. The public is not aware of the ailments — everyone can recognize malaria, but few connect blurry vision or exhaustion with hypertension — and primary care health workers often don’t know what to check for either.When Dr. Asiki’s organization set up random screenings in a low-income community in Nairobi a couple of years ago, researchers found that a quarter of adults had hypertension. But 80 percent of them did not know they had it. Of those who did, fewer than 3 percent were controlling their blood pressure with medication.A fraction of Kenya’s health budget goes to noncommunicable disease — it was 11 percent in 2017-18, the latest figures in the government’s strategic plan — and those funds are mostly earmarked for expensive curative services such as radiation machines at cancer clinics and kidney dialysis centers. “But people come with cancers that are already Stage 4, with very little chance of survival, because they cannot get diagnosed,” Dr. Asiki said.Government ministers like to cut the ribbon on new cancer centers, but there is no perceived political value in investing in a long-term screening program, said Catherine Karekezi, executive director of the Kenyan chapter of an international patient advocacy organization called the Noncommunicable Disease Alliance.“Eighty percent of deaths from noncommunicable disease in this country are from preventable causes,” Dr. Karekezi said. “We can prevent the causes, and if you do have the condition, we could prevent you from progressing to complications.”Azibeta Kamonga, 70, lives in the sprawling low-income community of Kibera, in the Kenyan capital. She was diagnosed with diabetes 17 years ago, but can rarely afford to buy medication, and often feels weak and dizzy.Malin Fezehai for The New York TimesInstead, she said, younger people are falling ill and developing serious complications, and are sometimes unable to work. “It’s the economically active segment of the population that is affected,” she said.People die of undiagnosed heart disease or complications from diabetes in their 50s and that’s chalked up to “old age.” The systems to accurately track causes of death are weak, which means that neither the public nor policymakers understand the true scale of the problem, Dr. Asiki said.Unlike H.I.V. medication and care, which is usually free and subsidized by international donors, treatment for diabetes or blood pressure are usually out-of-pocket expenses for families, and often cripplingly expensive, said Dr. Jean-Marie Dangou, who coordinates the noncommunicable disease program of the W.H.O.’s Africa regional office.“In the Democratic Republic of Congo, hypertension treatment is two-thirds of the typical household income each month,” he said. “That’s absurd, for that family. But it is not unusual.”Annah Mutindi, 42, used up all her savings from her job as a clerk in a Nairobi dress shop on doctor visits and tests before a painful lump in her breast was diagnosed as cancer in January 2021. She was prescribed a course of 12 biweekly sessions of chemotherapy. She could have had them for a minimal cost, in theory, at a large public hospital in the center of the city, but the treatment was continuously out of stock.Instead she had to wait until her family and friends scraped together $360 every few weeks so she could pay for the treatments one by one, stretched over the next nine months.“I was in shock when they told me it was cancer, because I never touch alcohol and I eat healthy,” Ms. Mutindi said, recalling her diagnosis. “They said maybe it was environmental factors.”The share of deaths caused by noncommunicable disease is increasing across the region, most rapidly in the continent’s most populous states, Dr. Dangou said. In Ethiopia, for example, mortality caused by these conditions climbed to 43 percent of deaths last year from 30 percent in 2015, and made a similar jump in the D.R.C. It is clear that rapid urbanization and an increase in sedentary lifestyles is driving some of the increase in these conditions. So is growing use of tobacco and alcohol, and consumption of processed foods. Kenya’s government has been slow to update policies to discourage these. And all three industries have powerful lobbying organizations that are focused on stalling legislation such as a tax on sugar-sweetened beverages. Kenya is a major producer of tobacco and the industry reminds the government of the jobs it creates, Dr. Asiki saidThere’s also the simple fact that people are living longer because of the progress fighting infectious diseases. But others causes, such as possible genetic factors and a correlation with exposure to infectious disease, are less understood.Annah Mutindi with her son, Joel, at the entrance to their apartment in Nairobi. Ms. Mutindi used up all her savings on doctor visits and tests to learn that a painful lump in her breast was cancer in January 2021.Malin Fezehai for The New York TimesThere is little public investment in researching the mystery of why noncommunicable disease rates are rising so quickly, and in comparatively younger people, in this region. The experience of high-income countries is of limited relevance to the situation in a country such as Kenya, Dr. Asiki said. Scarcity of nutritious food in childhood appears to prime people metabolically for obesity in adulthood. There is some evidence that malaria infections predispose people to cardiovascular disease; hepatitis infections put them at risk for cancer.Taking the antiretroviral drugs that control H.I.V. for years can lead to a higher risk of heart disease. Urban dwellers are also exposed to increased rates of air pollution and environmental toxins, and some to the stress of living in areas with high rates of violence and insecurity. All of these are contributing factors, Dr. Asiki said, but their combined effect is not yet well understood.Dr. Andrew Mulwa, who directs preventive and health promotion programs for the Kenyan Ministry of Health, said the government was concerned about the soaring rates of noncommunicable conditions, but that it was slow work rolling out diagnostics and treatment to the primary care level in rural areas.“When I worked as a clinician in a rural area 10 years ago, you would see 50 patients a day with these conditions, and now it is 500 to 1,000 at the same facility,” he said.Poor nutrition is influencing the rise of noncommunicable diseases in multiple ways — what Dr. Asiki calls “a double burden of under-nutrition.” This region is home to both the largest number of stunted children in the world and the fastest-rising rate of obesity.It is common in low-income households to find both malnourished children, who lack the protein and nutrients essential for growth, and adults who are obese, because they are reliant on cheap, fatty and energy-dense street foods — often a more affordable option than paying for vegetables and cooking gas to make food at home.“You can have enough of the bad food but scarcity of the needed foods,” Dr. Asiki said. “The body stores excess energy as fat — but at the end it’s still scarcity.”He speculated that the government had been slow to roll out screening programs because there was no way it could respond to the extent of the problem.“That’s when you suddenly realize, I don’t have enough medications for hypertension, I don’t have enough medications to treat people with cancer,” Dr. Asiki said. “If you screen, you will pick cases that are treatable. But do we have the resources to treat them?”

Some of the most fragile health systems in the world can teach us ways to respond to public health threats early and effectively.When Ebola swept through the eastern Democratic Republic of Congo in 2018, it was a struggle to track cases. Dr. Billy Yumaine, a public health official, recalls steady flows of people moving back and forth across the border with Uganda while others hid sick family members in their homes because they feared the authorities. It took at least a week to get test results, and health officials had difficulty isolating sick people while they waited.It took two years for the country to bring that outbreak under control, and more than 2,300 people died.A similar disaster threatened the D.R.C. last September. Members of a family in North Kivu Province fell ill with fevers, vomiting and diarrhea, one after the other. Then their neighbors became sick, too.But that set off a series of steps that the D.R.C. put in place after the 2018 outbreak. The patients were tested, the cases were quickly confirmed as a new outbreak of Ebola and, right away, health workers traced 50 contacts of the families.Then they fanned out to test possible patients at health centers and screened people at the busy border posts, stopping anyone with symptoms of the hemorrhagic fever. Local labs that had been set up in the wake of the previous outbreak tested more than 1,800 blood samples.It made a difference: This time, Ebola claimed just 11 lives.“Those people died, but we kept it to 11 deaths, where in the past we lost thousands,” Dr. Yumaine said.You probably didn’t hear that story. You probably didn’t hear about the outbreak of deadly Nipah virus that a doctor and her colleagues stopped in southern India last year, either. Or the rabies outbreak that threatened to race through nomadic Masai communities in Tanzania. Quick-thinking public health officials brought it in check after a handful of children died.Officials in Kerala, India, inspected a well to catch bats, which carry the deadly nipah virus, in 2018.Agence France-Presse — Getty ImagesOver the past couple of years, the headlines and the social feeds have been dominated by outbreaks around the world. There was Covid, of course, but also mpox (formerly known as monkeypox), cholera and resurgent polio and measles. But a dozen more outbreaks flickered, threatened — and then were snuffed out. While it may not feel that way, we have learned a thing or two about how to do this, and, sometimes, we get it right.A report by the global health strategy organization Resolve to Save Lives documented six disasters that weren’t. All emerged in developing countries, including those that, like the D.R.C.., have some of the most fragile health systems on earth.More on IndiaUrdu Poetry Festival: More than 300,000 people came to celebrate Urdu poetry during a three-day festival in New Delhi. It was testament to the peculiar reality of the language in India.Tourism in Kashmir: Visitors are flocking back to the region. Тhat is proof, India says, that its imposition of control worked. But people who live there say fear and uncertainty persist.A Deadly Bridge Collapse: After 134 people were killed when a pedestrian bridge collapsed in Gujarat, the country is asking why its infrastructure has failed so calamitously once again.Coal Baron or Climate Warrior?: The business decisions of Gautam Adani, Asia’s richest man, could go a long way in determining whether India helps the world avert a climate catastrophe.While cutting-edge vaccine technology and genomic sequencing have received lots of attention in the Covid years, the interventions that helped prevent these six pandemics were steadfastly unglamorous: building the trust of communities in the local health system. Training local staff in how to report a suspected problem effectively. Making sure funds are available to dispense swiftly, to deploy contact tracers or vaccinate a village against rabies. Increasing lab capacity in areas far from the main urban centers. Priming everyone to move fast at the first sign of potential calamity.“Outbreaks don’t occur because of a single failure, they occur because of a series of failures,” said Dr. Tom Frieden, the chief executive of Resolve and a former director of the United States Centers for Disease Control and Prevention. “And the epidemics that don’t happen don’t happen because there are a series of barriers that will prevent them from happening. .”Dr. Yumaine told me that a key step that made a difference in shutting down Congo’s Ebola outbreak in 2021 was having local health officials in each community trained in the response. The Kivu region has lived through decades of armed conflict and insecurity, and its population faces a near-constant threat of displacement. In previous public health emergencies, when people were told they would have to isolate because of Ebola exposure, they feared it was a trick to move them off their land.“In the past, it was always people from Kinshasa who were coming with these messages,” he said, referring to the country’s capital. But this time, the instructions about lockdowns and isolation came from trusted sources, so people were more willing to listen and be tested.Ebola prevention signage at a local health center in Madudu, Uganda, in October. Luke Dray/Getty Images“We could give local control to local people because they were trained,” he said.Because labs had been set up in the region, people with suspected Ebola could be tested in a day — two, at most — instead of waiting a week or more for samples to be sent more than 1,600 miles to Kinshasa. In the State of Kerala in southern India, Dr. Chandni Sajeevan, the head of emergency medicine at Kozhikode Government Medical College hospital, led the response to an outbreak of Nipah, a virus carried by fruit bats, in 2018. Seventeen of the 18 people infected died, including a young trainee nurse who cared for the first victims.“It was something very frightening,” Dr. Chandni said. The hospital staff got a crash course in intensive infection control, dressing up in the “moon suits” that seemed so foreign in the pre-Covid era. Nurses were distraught over the loss of their colleague.Three years later, in 2021, Dr. Chandni and her team were relieved when the bat breeding season passed with no infections. And then, in May, deep into India’s terrible Covid wave, a 12-year-old boy with a high fever was brought to a clinic by his parents. That clinic was full, so he was sent to the next, and then to a third, where he tested negative for Covid.But an alert clinician noticed that the child had developed encephalitis. He sent a sample to the national virology lab. It swiftly confirmed that this was a new case of Nipah virus. By then, the child could have exposed several hundred people, including dozens of health workers.The system Dr. Chandni and her colleagues had put in place after the 2018 outbreak kicked into gear: isolation centers, moon suits, testing anyone with a fever for Nipah as well as Covid. She held daily news briefings to quell rumors and keep the public on the lookout for people who might be ill — and away from bats and their droppings, which litter coconut groves where children play. Teams were sent out to catch bats for surveillance. Everyone who had been exposed to the sick boy was put into 21 days of quarantine.“Everyone, ambulance drivers, elevator operators, security guards — this time, they knew about Nipah and how to behave not to spread it,” she said.Health workers in Kerala collected blood samples from a goat to test for Nipah virus after a 12-year-old boy died in September 2021.Shijith. K/Associated PressDr. Amanda McLelland, who leads epidemic prevention at Resolve, told me that when she heard of new Ebola cases in Guinea in West Africa in 2021, she feared disaster. An outbreak that began in Guinea in 2014 had spread to two neighboring countries, and by the time it was declared over two years later, nearly 30,000 people had been infected and 11,325 had died.But this time, although Guinea was already struggling to respond to Covid, it managed to bring the Ebola outbreak in check in six months, with just 11 deaths.“That was a fantastic example of learning those lessons and investing and building sustainably in the capacity,” Dr. McLelland said.It should be celebrated, she added. While public health failures, such as those in the face of Covid, receive plenty of attention, she said, “our success is invisible.”Nevertheless, progress can be fitful: A new Ebola outbreak is slowly being brought under control in Uganda, and neighboring nations have watched it with concern. Dr. Frieden said he was discouraged to see this, because Uganda has a strong public health system with a track record of detecting and responding to outbreaks quickly.“I think what we’re seeing there is the unfortunate harvest of Covid. Covid broke a lot of things,” he said. “It broke health care worker resilience, it broke the willingness of many people to follow public health advice, it broke trust in the health care system and communities that was there before. Progress is possible, but it’s also fragile.”But Dr. Yumaine said he had growing confidence that even if Ebola were to spill back across the border from Uganda, the D.R.C. could respond swiftly, with surveillance systems that grow better all the time.“We’re encouraged by our improvements,” he said. “But we’re not stopping there.”

Many of the poorest countries will continue to get free Covid shots, but global demand for them has plummeted, driving a shift away from the goal of broad coverage.A key partner in Covax, the organization that has led the effort to bring Covid vaccines to poor and middle-income countries, will stop supplying the shots to a huge part of the global population in the year ahead, and provide them only to the lowest-income nations.The board of governors of Gavi, the nonprofit that supplies immunizations to developing countries, voted at a meeting in Geneva on Thursday to end Covax support for 37 countries, including Egypt and Indonesia, where hundreds of thousands of people have died from the coronavirus.Fifty-four other nations, including some of the world’s poorest countries, will continue to receive free Covid shots and funds to help deliver them — if they want them — going into 2025.The decision reflects the fact that demand for Covid vaccines has plummeted worldwide, and that Gavi has found itself overcommitted to vaccine purchases when countries don’t want them. The continuing vaccination efforts are expected to focus on high-risk groups, including older and immunocompromised people.Covax has delivered 1.7 billion Covid shots to people in developing nations, in challenging circumstances, but has fallen far short of its goal of ensuring equitable access to the vaccines worldwide. The effort was hobbled at the outset by high-income countries that locked up the initial supply of shots, and later by erratic supply flows and weak delivery systems.Read More on the Coronavirus PandemicCases and Apathy Rise: The United States is once again experiencing an uptick in cases in the weeks after Thanksgiving. But fear — and masks — are missing this time around.A Crisis for the Uninsured: As federal funding for the pandemic response dries up, Americans without health insurance risk being left footing the bill for tests and treatments.Long Covid: People who took the antiviral drug Paxlovid within a few days after being infected with the coronavirus were less likely to experience long Covid months later, a study found.Calls for a New Strategy: Covid boosters can help vulnerable Americans dodge serious illness or death, but some experts believe the shots must be improved to prevent new waves.Today, vaccination rates in the countries served by Covax sit at an average of 52 percent of the population receiving initial Covid inoculation. But the figure for sub-Saharan Africa is just 26 percent. Delivery of booster doses has stalled across developing nations, and Covid cases are rising around the world. “It’s alarming that this decision has been made while the pandemic is still ongoing and without thorough consultation with these countries,” said Kate Elder, the senior vaccines policy adviser for Doctors Without Borders’ access campaign.But Dr. Anthony Mounts, director of the Covid vaccine introduction program at the Task Force for Global Health, a nonprofit organization that has supported Covid vaccination delivery in 37 developing countries, said the decision seemed inevitable in the face of the across-the-board lack of interest in Covid vaccines he had seen. The World Health Organization estimates that 90 percent of the world population now has some immunity to Covid-19, from vaccination or previous infection.“In spite of whatever challenges Covax faced, I think just the fact that there was a coordinating mechanism was extremely useful,” Dr. Mounts said. “But it’s time to change our direction and really focus on high-risk groups and what we can do to protect them.”Palestinian Health Ministry staff members unloading 300,000 doses of Covid-19 vaccines provided by Covax in 2021.Jaafar Ashtiyeh/Agence France-Presse — Getty ImagesThe 37 countries for which support is ending will receive a one-time payment, which the board described as “catalytic,” to set up their own Covid vaccination programs. The other 54 are nations that received support from Gavi for routine immunization before the pandemic. If those countries choose to continue with Covid campaigns, Gavi will move to integrate Covid shots into the regular support it offers, ending the emergency program.“We’re as committed as we were from Day 1 to helping countries reach their national targets and boost the most vulnerable,” Aurelia Nguyen, Gavi’s chief programming and strategy officer, said. “At the same time, we need to plan for any potential worst-case scenario and find ways of gaining efficiencies for countries” by adding Covid-19 shots to regular vaccination programs.The World Health Organization, another partner in Covax, continues to maintain a goal of vaccinating 70 percent of the population in each country. The W.H.O. did not respond to a request for comment on the Gavi board decision.Gavi, using funds from rich nations, negotiates purchases with vaccine makers on behalf of Covax, and also channels money to countries to help administer shots. The agency has also received millions of doses of vaccines as donations, the tide of which has ballooned as high-income nations — which have seen their own vaccine programs falter — seek to offload their oversupply.Budget documents presented to the Gavi board show that the organization has had to renegotiate its vaccine contracts to get out of having to buy hundreds of millions of doses, and that countries have been slow to use the funds they were given to administer the shots.The Gavi board directed the organization’s staff to update donors early in 2023 on how it suggests using the money currently sitting in the pool to buy vaccines. It also gave broad approval to a plan for Gavi to create a $1.5 billion pandemic preparedness pool.At the meeting, Gavi’s governors recommitted the organization to trying to catch up on a critical drop in routine childhood vaccinations that has occurred over the course of the Covid pandemic and led to resurgences of diseases including polio and measles.In addition, the Gavi board voted to restart a vaccination campaign against the human papillomavirus, or HPV, with an investment of $600 million, in an effort to try to reach 86 million girls by 2025 with the vaccine, which aims to prevent cervical cancer.And, going forward, Gavi will invest in efforts to expand the manufacturing of vaccines in Africa, as part of an effort to prevent the kind of disparity seen early in the Covid pandemic when vaccine nationalism left the continent with no access to shots.