Vaccines today are more efficient and contain far fewer stimulants to the immune system than some used decades ago. It’s an idea as popular as it is incorrect: American babies now receive too many vaccines, which overwhelm their immune systems and lead to diseases like autism.This theory has been repeated so often that it has permeated the mainstream, echoed by President-elect Donald J. Trump and his pick to be the nation’s top health official, Robert F. Kennedy Jr.“When you feed a baby, Bobby, a vaccination that is, like, 38 different vaccines and it looks like it’s been for a horse, not a, you know, 10-pound or 20-pound baby,” Mr. Trump told Mr. Kennedy on a call in July. “And then you see the baby all of a sudden starting to change radically — I’ve seen it too many times.”On Sunday, Mr. Trump returned to the theme, saying Mr. Kennedy would investigate whether childhood vaccines caused autism, even though dozens of rigorous studies have already explored and dismissed that theory.“I think somebody has to find out,” Mr. Trump said on NBC’s “Meet the Press.”But the idea that today’s vaccines are overtaxing children’s immune systems is fundamentally flawed, experts said. Vaccines today are cleaner and more efficient, and they contain far fewer stimulants to the immune system — by orders of magnitude — than they did decades ago.What’s more, the immune reactions produced by vaccines are “minuscule” compared with those that children experience on a daily basis, said Dr. Yvonne Maldonado, a pediatrician at Stanford University who advises the Centers for Disease Control and Prevention on vaccines.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Rates of gonorrhea declined in 2023, while diagnoses of syphilis and chlamydia held roughly steady, according to new C.D.C. data.After decades of unrelenting increases, rates of sexually transmitted infections in the United States are showing hints of a downturn.Diagnoses of gonorrhea dipped in nearly all age groups last year, compared with 2022, and new cases of syphilis and chlamydia remained about the same, according to data released on Tuesday by the Centers for Disease Control and Prevention.The results are not yet cause for celebration.Overall, more than 2.4 million new S.T.I.s were diagnosed last year, about a million more than the figure 20 years ago. Nearly 4,000 babies were diagnosed with congenital syphilis last year, and 279 of them were stillborn or died soon after.Still, experts said they were cautiously optimistic that a resurgent tide of infections was beginning to turn.“It’s been a long time since I have felt that way about the S.T.I. epidemic,” said Dr. Jonathan Mermin, director of the National Center for H.I.V., Viral Hepatitis, S.T.D. and TB Prevention at the C.D.C.The drop in cases may be the result of a variety of factors: an infusion of funds into health departments during the Covid-19 pandemic, changes in sexual behavior among gay and bisexual men because of the mpox outbreak in 2022 and the recent availability of the antibiotic doxycycline to forestall S.T.I.s after unprotected sexual encounters.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The epidemic in Africa continues to grow, prompting fears of another outbreak in the U.S. But the vaccine is no longer free, and vulnerable people are going without.A particularly deadly form of mpox, formerly called monkeypox, has led to more than 48,000 cases and more than 1,100 deaths in Africa this year. The Biden administration has donated one million doses of the vaccine to affected countries.But in the United States, mpox vaccines are out of reach for many people who need them.In the 2022 outbreak that reached this country, doses of the mpox vaccine, Jynneos, were made available for free from the federal stockpile. That arrangement ended in April, when the vaccine became available commercially.But insurance companies do not yet cover the vaccine or, if they do, reimburse only a tiny fraction of the cost. Some young gay or bisexual men hesitate to use insurance, because they are not out to their families.And some people at high risk of mpox, including those with H.I.V., are less likely to have any form of insurance at all.“This is a massive bump in the road, and especially because it’s happening in the middle of deep concern about another outbreak,” said Dr. Stacey Trooskin, executive medical officer of the Mazzoni Center, a large sexual health clinic that serves the L.G.B.T.Q. community in Philadelphia.The virus circulating in Africa has not yet reached the United States. Still, the outbreak overseas has led to a rise in the number of Philadelphia residents seeking the vaccine.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Breaking up the C.D.C., moving funds from the N.I.H. — conservatives have floated changes should Mr. Trump regain office.The Covid pandemic dominated the last years of Donald Trump’s presidency, and the discontent it caused most likely contributed to his loss in 2020. But on the campaign trail this year, Mr. Trump rarely talks in depth about public health, dwelling instead on immigration, the economy and his grievances.Still, Project 2025, the blueprint for a new Republican administration shaped by many former Trump staff members, lays out momentous changes to the Food and Drug Administration, the Centers for Disease Control and Prevention, and the National Institutes of Health.And Mr. Trump’s embrace of Robert F. Kennedy Jr., a vaccine skeptic, and his campaign slogan, “Make America Healthy Again,” suggests there will be significant changes to the nation’s public health priorities should Mr. Trump regain the presidency.“I’m going to let him go wild on health,” Mr. Trump said of Mr. Kennedy at a rally in New York City on Sunday. “I’m going to let him go wild on the food. I’m going to let him go wild on medicines.”Republican critics increasingly describe the health agencies as corrupt, riddled with conflicts of interest and staffed by myopic bureaucrats accountable to no one.Mr. Trump echoed these themes at a rally in Wisconsin: “We’ll take on the corruption at the F.D.A., the C.D.C., World Health Organization and other institutions of public health that have dominated, and really are dominated by corporate power, and dominated really by China.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Supplies of a highly nutritious treatment are running out, according to UNICEF.Nearly two million children may die of malnutrition because a product used to treat the condition is in short supply, the United Nations Children’s Fund said on Monday.Four countries — Mali, Nigeria, Niger and Chad — have exhausted their supplies of the peanut-based, high-nutrient product, called ready-to-use therapeutic food, or are on the brink of doing so. Another eight nations, including South Sudan, the Democratic Republic of Congo and Uganda, could run out by mid-2025.“Urgent action is needed now to save the lives of nearly two million children who are fighting this silent killer,” Victor Aguayo, UNICEF’s director for child nutrition and development, said in a statement.Severe acute malnutrition, or wasting, can result from poor nutrition during gestation and in infancy, limited access to safe drinking water, and relentless attacks by multiple infections.The children may be stunted and may have prominent ribs and other bones, dry skin and brittle hair. They are diagnosed with the condition when they have a very low weight for their height (or length, in the case of infants); a mid-upper arm circumference of less than 4.5 inches; or a buildup of fluid in the legs, arms and face.Severe acute malnutrition affects an estimated 19 million children under the age of 5 worldwide and may account for about 400,000 deaths among children each year, according to the World Health Organization.Children who are severely malnourished have weak immune defenses, leaving them vulnerable to the diseases that circulate in poorer countries, particularly in crisis zones, such as diarrhea, pneumonia, malaria and measles.UNICEF relies on ready-to-use therapeutic food to treat children with severe wasting. Other organizations use similar products to help children at less serious stages of malnutrition. Children may need the food, along with medical care, for up to eight weeks before they are beyond danger.UNICEF estimated that in 2023, the food reached about 73 percent of the children in need and averted the deaths of 1.2 million children younger than 5.But war, civil conflicts, climate change and economic crises that have derailed global supply chains have all contributed to hunger emergencies, as have prolonged droughts and floods in the Sahel region of Africa.In Mali, supplies of the food began running low in late July. In Chad and Niger, it is expected to run out by the end of this month, and in Cameroon by the end of the year.Since 2022, UNICEF has raised about $933 million to support its malnutrition programs. It is now calling for donations of $165 million to refresh supplies of R.U.T.F., in addition to a $100 million donation that the United States recently made.

Both patients were dairy workers whose illnesses were mild. Investigators are continuing to evaluate the contacts of a Missouri patient who had no exposure to animals.Two more people were diagnosed with bird flu this week, even as scientists in Missouri continued to investigate a possible cluster of infections in that state, federal health officials said at a news briefing on Friday.In California, two farmworkers who were exposed to infected dairy cattle at different farms tested positive for the virus, called H5N1, state health officials said on Thursday. Those cases bring the total this year to 16, not including those under investigation.The cases do not come as a surprise, because the number of infected herds in California has risen to 56 from 16 two weeks ago, said Dr. Nirav Shah, the principal deputy director at the Centers for Disease Control and Prevention.“As there are more herds that test positive, there are more workers who are exposed, and where there are more workers who are exposed, the chances of human infection increase,” he said. The risk to the public remains low, he added.Still, experts said that the appearance of H5N1 in multiple states was worrisome. Flu viruses are adept at acquiring new abilities by swapping their genes. As the flu season swings in, even one person who becomes infected with both bird flu and the seasonal flu virus could help H5N1 to gain the ability to spread as readily among people as seasonal flu does.Given the many variables, it’s difficult to gauge the true risk of the virus mutating into a more contagious form, said Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Center in Seattle.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

From Covid to dengue, viral outbreaks seemed to be popping up all over. But maybe Americans are just more attuned to threats now.Bird flu. Mpox, formerly monkeypox. Eastern equine encephalitis. West Nile. Listeria. Dengue. Oropouche. And, of course, Covid.Have the past few months felt like an unending parade of infectious disease?A plethora of pathogens dominated headlines all summer, and some of that attention may have been warranted: Oropouche, a tropical infection, and dengue devastated South America; mpox is ravaging parts of Africa; and bird flu holds the potential to flare into a dangerous pandemic.But in the United States, the threat to public health was much less alarming than it may have seemed.Mosquitoes sickened some Americans with infections like dengue, malaria, West Nile virus and Eastern equine encephalitis. But with the exception of dengue, the viruses were less of a problem, or at least no worse, this year than last year.The major public health troublemakers were familiar foes: Covid, measles and whooping cough, along with a litany of noninfectious threats, including drug overdoses, heart disease and cancer, said Dr. Mandy Cohen, director of the Centers for Disease Control and Prevention.What has changed is how attuned to new pathogens many Americans are after the coronavirus pandemic, she added.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

In 2016, the global health authorities removed a type of poliovirus from the oral vaccine. The virus caused a growing number of outbreaks and has now arrived in Gaza.The poliovirus that paralyzed a child in Gaza, the first case in the region in 25 years, has traveled a long path.It most likely arose in Nigeria and made its way to Chad, where it was first detected in 2019, according to genetic analysis. It emerged in Sudan in 2020 and then found a foothold in Egypt, in unvaccinated pockets of Luxor and North Sinai — next door to Gaza.This journey was the consequence of a fateful decision by global health organizations to pare down the oral polio vaccine in 2016. The move, now called “the switch,” was intended to help eradicate the disease.Instead, the change has led to outbreaks of polio in dozens of countries and has paralyzed more than 3,300 children. A formal evaluation, commissioned by the global polio eradication program and led by two independent experts, was unflinching in its assessment: “The switch was an unqualified failure.”One consequence now is the furious scramble to vaccinate hundreds of thousands of children in a decimated conflict zone, just the sort of environment in which polio thrives. It’s not yet clear whether the virus can be contained in Gaza.Health workers carry polio vaccines during a campaign in central Gaza. So far, the workers have succeeded in immunizing many more children than expected. Eyad Baba/Agence France-Presse — Getty ImagesWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Previous human infections occurred in workers on farms. But community transmission of the virus remains unlikely for now, experts said.Officials in Missouri on Friday identified the first American infected with bird flu who had no known exposure to the infected animals or birds that have been plaguing the nation’s farms for more than six months.The case brings this year’s number of human bird-flu infections to 14. Previous human cases were all acquired from interactions with infected dairy cattle or poultry. The new patient raises the unsettling possibility that the virus, called H5N1, may be spreading undetected among people.How the person became infected is unknown, but Missouri health officials said they are trying to pinpoint the source.“The route of transmission is going to determine how much more escalated the risk of the disease is to the general public,” said Dr. Nahid Bhadelia, director of Center on Emerging Infectious Diseases at Boston University.The case was picked up by routine seasonal flu surveillance conducted in Missouri, where the person was hospitalized, and not during an investigation on a farm. The state has not reported any infections on its cattle farms, but has detected the virus in some commercial and backyard flocks, as well as in wild birds.Since March, the bird flu virus has been found in nearly 200 dairy herds in 14 states, although testing has not been conducted widely enough to gauge the full spread. California, the nation’s largest milk producer, found bird flu in three cattle herds last week.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The virus is poised to become a permanent presence in cattle, raising the odds of an eventual outbreak among people.Without a sharp pivot in state and federal policies, the bird flu virus that has bedeviled American farms is likely to find a firm foothold among dairy cattle, scientists are warning.And that means bird flu may soon pose a permanent threat to other animals and to people.So far, this virus, H5N1, does not easily infect humans, and the risk to the public remains low. But the longer the virus circulates in cattle, the more chances it gains to acquire the mutations necessary to set off an influenza pandemic.“I think the window is closing on our ability to contain the outbreak,” said Dr. Krutika Kuppalli, an infectious-disease physician who worked at the World Health Organization until April.“We’re so quick to blame China for what happened with SARS-CoV-2, but we’re not doing any better right now,” she added. “That’s how pandemics happen.”Half a year into the outbreak, H5N1 shows no signs of receding in U.S. dairy cattle or in the workers who tend them. In recent weeks, the virus has spread into poultry and workers.As of Wednesday, infections had been reported in 192 herds of cattle in 13 states, and in 13 people. Nine were workers at poultry farms close to dairy farms in Colorado.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.