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The European Society of Cardiology (ESC) Guidelines for the diagnosis and treatment of acute and chronic heart failure are published online today in European Heart Journal. This was the first ESC Guideline to include patients as full members of the task force.
Approximately 2% of adults worldwide have heart failure. Prevalence increases with age, from 1% in those under 55 years to more than 10% in people aged 70 and above. In developed countries, the most common causes are coronary artery disease and high blood pressure. Patients with heart failure have a poor prognosis and markedly reduced quality of life. The main symptoms are breathlessness, ankle swelling, and tiredness. After diagnosis, patients are hospitalised once every year on average and more than half die within five years.
Chronic heart failure is a condition where the heart is unable to pump blood around the body properly. It usually occurs because the heart has become too weak or stiff. Ejection fraction, i.e. the percentage of the blood within the ventricles that is ejected during the cardiac cycle, is the most important measurement of cardiac function. When the pumping action of the heart is weak it is referred to as “heart failure with reduced ejection fraction” and when it is stiff and does not relax properly, it is referred to as “heart failure with preserved ejection fraction.” Acute heart failure is a life-threatening condition requiring urgent evaluation and treatment; it may be the first manifestation of heart failure (new onset) or, more frequently, it is due to an acute deterioration of chronic heart failure.
Regarding diagnosis, when there is a suspicion of chronic heart failure, the guidelines recommend measuring the level of hormones produced by the heart (natriuretic peptides). If levels are normal the patient can be reassured that heart failure is very unlikely. If high, this should prompt referral for an echocardiogram to detect the underlying heart problem.
All heart failure patients are normally treated with diuretics to reduce breathlessness and ankle swelling. For heart failure with reduced ejection fraction, there are many drug treatments that improve survival, namely angiotensin?converting enzyme (ACE) inhibitors, angiotensin-receptor neprilysin inhibitors (ARNIs), beta-blockers and mineralocorticoid receptor antagonists (MRAs). In addition, the guidelines recommend a new class of drugs, the sodium-glucose co-transporter-2 (SGLT2) inhibitors, also called gliflozins, as both dapagliflozin and empagliflozin reduce the risk of cardiovascular death and/or hospitalisations for heart failure when added to standard treatment. Some patients with heart failure with reduced ejection fraction may also benefit from devices such as defibrillators and cardiac resynchronisation therapy pacemakers.
The guidelines state that no treatment has been shown to reduce mortality and morbidity in patients with heart failure with preserved ejection fraction to date.
Exercise is recommended for all capable chronic heart patients to improve quality of life and reduce heart failure hospitalisation. In those with more severe disease, frailty, or comorbidities, a supervised, exercise-based, cardiac rehabilitation programme should be considered. “The vast majority of drug treatments that improve survival and reduce hospitalisations also have beneficial effects on quality of life and symptoms,” said guidelines task force chairperson Professor Theresa McDonagh of King’s College Hospital, London, UK. “There are some interventions that do not impact survival but do improve quality of life and symptoms — for example exercise rehabilitation — that should also be offered to patients with chronic heart failure.”
The guidelines recommend that all patients have access to a multi-professional heart failure disease management programme to ensure that their heart failure is correctly diagnosed and managed. These programmes have been associated with better care and improved outcomes. In addition, patients with heart failure should be encouraged to be actively involved in managing their condition. Self-care includes adopting healthy habits such as physical activity, avoiding excessive salt intake, maintaining a healthy body weight, avoiding excessive alcohol consumption, and not smoking. It is also important to avoid drinking large volumes of fluid, recognise sleeping problems, monitor changes in symptoms, and know when to contact a health professional.
Patients with heart failure are at increased risk of infections, which may worsen symptoms and be a precipitant factor for acute heart failure. The guidelines state that influenza, pneumococcal and COVID-19 vaccination should be considered in patients with heart failure.
The guidelines provide general advice on how to prevent heart failure. This includes regular physical activity, not smoking, healthy diet, no/light alcohol intake, influenza vaccination, and treatment of high blood pressure and high cholesterol. Recommendations are also given on how to manage patients with heart failure who have co-existing conditions such as atrial fibrillation and valvular heart disease. “It is crucial to treat the underlying causes of heart failure and its comorbidities,” said guidelines task force chairperson Professor Marco Metra of the University of Brescia, Italy. “Proper treatment of high blood pressure, diabetes and coronary artery disease can prevent the development of heart failure. Atrial fibrillation, valvular heart disease, diabetes, chronic kidney disease, iron deficiency and other comorbidities frequently co-exist with heart failure and the adoption of specific treatments may have a major impact on the clinical course of our patients.”

As the COVID-19 pandemic swept the globe in 2020, musicians around the world were desperate for the answers to two pressing questions: Can playing musical instruments transmit COVID-19? And if so, what can be done?
Now, halfway through 2021, the first official research results are in — and it’s good news: The show can go on.
Published today in the journal ACS Environmental Au, University of Colorado Boulder and University of Maryland researchers have found that while playing musical instruments can emit the same levels of potentially COVID-laden airborne particles as singing, simple safety measures, such as masking instruments, social distancing and implementing time limits, significantly reduce this risk.
“COVID has shown people that aerosol transmission of respiratory diseases is something that happens. But just because it goes into the air doesn’t mean that everyone is going to contract this disease. We found that there are ways to mitigate these aerosols in a space and ways to reduce your risk,” said Tehya Stockman, lead author of the paper and graduate student in mechanical engineering.
This research began in earnest in 2020 at CU Boulder and the University of Maryland to find out if playing musical instruments carried the same risks of COVID-19 transmission as singing is shown to have. While there have been no reported outbreaks from instrumental ensembles, these published findings echo the researchers’ initial hypotheses and recommendations that were eagerly accepted early on in the pandemic by musicians and performing groups worldwide.
“I want to acknowledge the courage of the music directors and the teachers to go ahead and follow our suggestions in the face of all of this adversity, fear and worry,” said Shelly Miller, co-author of the study and professor of mechanical and environmental engineering. “That really meant a lot to us because they trusted our very good research methods, our researchers and the evolution of science as it moves from: we don’t know, to, let’s find out, to OK — now we know this.”
These findings not only apply to the specific musical applications in which they have been tested, they also further validate that masking works as an effective mitigation technique, and ventilation and social distancing are important to reduce transmission, said Miller. Miller said she hopes these findings will further inspire a paradigm shift focused on mitigation measures and ventilation in order to reduce airborne transmission of infectious diseases.

A baby born prematurely often has to be separated from its parents and placed in an incubator in intensive care. For several weeks, he or she will undergo routine medical procedures that can be painful, without being relieved by too many pharmaceutical painkillers, which are risky for his or her development. So how can we act for the good of the baby? A team from the University of Geneva (UNIGE), in collaboration with the Parini Hospital in Italy and the University of Valle d’Aosta, observed that when the mother spoke to her baby at the time of the medical intervention, the signs of the baby’s expression of pain decreased and his oxytocin level — the hormone involved in attachment and also linked to stress — increased significantly, which could attest to better pain management. These results, to be read in the journal Scientific Reports, demonstrate the importance of parental presence with premature babies, who are subjected to intense stress from birth, a presence that has a real impact on their well-being and development.
As soon as they are born before 37 weeks of gestation, premature babies are separated from their parents and placed in an incubator, often in intensive care. They have to undergo daily medical interventions, necessary to keep them alive (intubation, blood sampling, feeding tube, etc.), which have potential impacts on their development and pain management. The difficulty? It is not always possible to relieve them with pharmaceutical painkillers, as the short and long term side effects on their neurological development can be significant. There are other ways to relieve the baby, such as wrapping, restraint, sugar solutions or non-nutritive sucking with a teat.
However, for several years now, studies have shown that the presence of a mother or father has a real calming effect on the child, particularly through the emotional modulations of the voice. This is why the team of Didier Grandjean, full professor at the Psychology Section of the Faculty of Psychology and Educational Sciences (FPSE) and at the Swiss Center for Affective Sciences (CISA) of the UNIGE, has been interested in the early vocal contact between the mother and the premature baby, in the impact of the mother’s voice on the management of pain resulting from the routine practices necessary for the follow-up of the babies, and in the psychological and cerebral mechanisms that would be involved.
Including the mother in the heel prick
To test this hypothesis, the scientists followed 20 premature babies at the Parini Hospital in Italy and asked the mother to be present during the daily blood test, which is done by extracting a few drops of blood from the heel. “We focused this study on the maternal voice, because in the first days of life it is more difficult for the father to be present, due to working conditions that do not always allow days off,” says Dr. Manuela Filippa, a researcher in Didier Grandjean’s group and first author of the study.
The study was conducted in three phases over three days, allowing for comparison: a first injection was taken without the mother being present, a second with the mother talking to the baby and a third with the mother singing to the baby. The order of these conditions changed randomly. “For the study, the mother started talking or singing five minutes before the injection, during the injection and after the procedure,” says the Geneva researcher. We also measured the intensity of the voice, so that it would cover surrounding noise, as intensive care is often noisy due to ventilations and other medical devices.
Signs of pain expression significantly reduced
First, the research team observed whether the baby’s pain decreased in the presence of the mother. To do this, they used the Preterm Infant Pain Profile (PIPP), which establishes a coding grid between 0 and 21 for facial expressions and physiological parameters (heartbeat, oxygenation) attesting to the baby’s painful feelings. “In order to code the behavior of premature babies, we filmed each blood test and judged the videos ‘blind’, by trained personnel, without sound, so as not to know whether the mother was present or not,” notes Didier Grandjean.
The results are significant: the PIPP is 4.5 when the mother is absent and drops to 3 when the mother talks to her baby. “When the mother sings, the PIPP is 3.8. This difference with the spoken voice can be explained by the fact that the mother adapts her vocal intonations less to what she perceives in her baby when she sings, because she is in a way constrained by the the melodic structure, which is not the case when she speaks,” emphasizes the Geneva professor.
Maternal voice induces an increase in oxytocin
The scientists then looked at what changes in the baby when it hears its mother speak. “We quickly turned to oxytocin, the so-called attachment hormone, which previous studies have already linked to stress, separation from attachment figures and pain,” explains Dr. Manuela Filippa. Using a painless saliva sample before the mother spoke or sang and after the heel prick, the research team found that oxytocin levels rose from 0.8 picograms per milliliter to 1.4 when the mother spoke. “In terms of oxytocin, this is a significant increase,” she says.
These results show the positive impact of the mother’s presence when premature babies undergo painful medical procedures. “We demonstrate here the importance of bringing parents and child together, especially in the delicate context of intensive care,” Manuela Filippa emphasizes. “Furthermore, parents play a protective role here and can act and feel involved in helping their child to be as well as possible, which strengthens the essential attachment bonds that are taken for granted in a full-term birth,” concludes Didier Grandjean.

Cutting 20% of sugar from packaged foods and 40% from beverages could prevent 2.48 million cardiovascular disease events (such as strokes, heart attacks, cardiac arrests), 490,000 cardiovascular deaths, and 750,000 diabetes cases in the U.S. over the lifetime of the adult population, according to micro-simulation study published in Circulation.
A team of researchers from Massachusetts General Hospital (MGH), the Friedman School of Nutrition Science & Policy at Tufts University, Harvard T.H. Chan School of Public Health and New York City Department of Health and Mental Hygiene (NYC DOH) created a model to simulate and quantify the health, economic, and equity impacts of a pragmatic sugar-reduction policy proposed by the U.S. National Salt and Sugar Reduction Initiative (NSSRI). A partnership of more than 100 local, state and national health organizations convened by the NYC DOH, the NSSRI released draft sugar-reduction targets for packaged foods and beverages in 15 categories in 2018. This February, NSSRI finalized the policy with the goal of industry voluntarily committing to gradually reformulate their sugary products.
Implementing a national policy, however, will require government support to monitor companies as they work toward the targets and to publicly report on their progress. The researchers hope their model will build consensus on the need for a national-sugar reformulation policy in the US. “We hope that this study will help push the reformulation initiative forward in the next few years,” says Siyi Shangguan, MD, MPH, lead author and attending physician at MGH. “Reducing the sugar content of commercially prepared foods and beverages will have a larger impact on the health of Americans than other initiatives to cut sugar, such as imposing a sugar tax, labeling added sugar content, or banning sugary drinks in schools.”
Ten years after the NSSRI policy goes into effect, the U.S. could expect to save $4.28 billion in total net healthcare costs, and $118.04 billion over the lifetime of the current adult population (ages 35 to 79), according to the model. Adding the societal costs of lost productivity of Americans developing diseases from excessive sugar consumption, the total cost savings of the NSSRI policy rises to $160.88 billion over the adult population’s lifetime. These benefits are likely to be an underestimation since the calculations were conservative. The study also demonstrated that even partial industry compliance with the policy could generate significant health and economic gains.
The researchers found that the NSSRI policy became cost-effective at six years and cost-saving at nine years. The policy could also reduce disparities, with the greatest estimated health gains among Black and Hispanic adults, and Americans with lower income and less education — populations that consume the most sugar as a historical consequence of inequitable systems.
Product reformulation efforts have been shown to be successful in reducing other harmful nutrients, such as trans fats and sodium. The U.S., however, lags other countries in implementing strong sugar-reduction policies, with countries such as the UK, Norway, and Singapore taking the lead on sugar-reformulation efforts. The US may yet become a leader in protecting its people from the dangers of excessive sugar consumption if the NSSRI’s proposed sugar-reduction targets are achieved. “The NSSRI policy is by far the most carefully designed and comprehensive, yet achievable, sugar-reformulation initiative in the world,” says Shangguan.
Consuming sugary foods and beverages is strongly linked to obesity and diseases such as type 2 diabetes and cardiovascular disease, the leading cause of mortality in the U.S. More than two in five American adults are obese, one in two have diabetes or prediabetes, and nearly one in two have cardiovascular disease, with those from lower-income groups being disproportionately burdened.
“Sugar is one of the most obvious additives in the food supply to reduce to reasonable amounts,” says Dariush Mozaffarian, MD, DrPH, co-senior author and dean of the Friedman School of Nutrition Science and Policy at Tufts University. “Our findings suggest it’s time to implement a national program with voluntary sugar reduction targets, which can generate major improvements in health, health disparities, and healthcare spending in less than a decade.”
Major funding for this study provided by the National Institutes of Health.
Shangguan is an attending at MGH and an instructor of Medicine at Harvard Medical School. Mozaffarian is dean of the Friedman School of Nutrition Science and Policy at Tufts University. Thomas Gaziano, MD, MSc, is associate professor at Brigham and Women’s Hospital and assistant professor of Medicine at HMS. Renata Micha, PhD, is research associate professor at the Friedman School of Nutrition Science and Policy at Tufts University and associate professor at the University of Thessaly in Greece.

The world’s first feasibility study has found that drones can be used to deliver life-saving defibrillators to people with suspected cardiac arrest in the community. The research is presented at ESC Congress 20211,2 and published in the European Heart Journal.3
“Drones delivered an automated external defibrillator (AED) just outside the door of residential homes, where most cardiac arrests occur, as well during the first minutes of a cardiac arrest,” said study author Dr. Sofia Schierbeck of Karolinska University Hospital, Stockholm, Sweden. “When a drone arrived before the ambulance it was nearly two minutes quicker. As drone technology improves it should be possible to increase the number of patients and the time benefits.”
Cardiac arrest is a life-threatening condition where the heart suddenly stops. It is fatal without cardiopulmonary resuscitation and an electric shock from an AED. Each minute without treatment decreases the chance of survival. It is estimated that cardiac arrest causes one in five deaths in industrialised countries.4 Survival has not increased over the years, and the mortality rate is 90%.5
Dr. Schierbeck said: “Emergency medical service response times are getting longer and people rarely have an AED at home. We believe that novel ways to provide AEDs are needed to increase the chance of survival in these patients. Therefore, we performed the first ever study to investigate the feasibility of drone delivery of AEDs to patients with suspected cardiac arrest outside of hospital.”
The study was conducted in the Gothenburg city area in western Sweden within the controlled airspace of an airport. The usual procedure when a suspected cardiac arrest occurs outside of hospital is that a witness calls the emergency number (112 in Sweden), and the dispatch centre sends an alarm to the ambulances that then drive as quickly as possible to the scene.
In this study, as a complement, three drones were set up in three different locations, each with a 5 km radius flight range. When a suspected cardiac arrest occurred in one of these three areas, the dispatch centre also sent an alarm to the drone pilots at the control centre for the drones. The drone pilot then contacted the air traffic control tower and if they approved the flight a drone was deployed. The automated drone system was surveilled by the drone pilot and when it arrived at the scene the drone descended to 30 m altitude before an AED was slowly winched down. The bystander with the victim then retrieved the AED, which was beeping to attract attention.

Research from a large international effort shows that 20% of children with cancer who are infected with SARS-CoV-2 develop severe infections. In studies of children overall, only 1-6% have reported severe infections. The results come from the Global Registry of COVID-19 in Childhood Cancer, which was launched by St. Jude Children’s Research Hospital and the International Society of Paediatric Oncology (SIOP). The registry gathers data on the pandemic’s effect on this unique patient population. The findings were published today in The Lancet Oncology.
Results from the registry indicated that in addition to more severe or critical infections, pediatric cancer patients were more likely to be hospitalized and die than were other children. The pandemic also disrupted cancer treatment. These effects were observed more significantly in low- and middle-income countries, where the odds of severe or critical disease from COVID-19 were nearly 6 times higher than in high-income countries.
“The results clearly and definitively show that children with cancer fare worse with COVID-19 than children without cancer,” said corresponding author Sheena Mukkada, M.D., St. Jude Departments of Global Pediatric Medicine and Infectious Diseases. “This global collaboration helps clinicians make evidence-based decisions about prevention and treatment, which, unfortunately, remain relevant as the pandemic continues.”
A greater burden for childhood cancer patients
This is the first multinational study to describe the outcomes of a large cohort of children and adolescents with cancer or hematopoietic stem cell transplantation and laboratory diagnosis of COVID-19. The registry remains open and is enrolling children younger than 19 years old.
The analysis looked at 1,500 children from 131 hospitals in 45 countries from April 15, 2020, to February 1, 2021. This is prior to vaccinations becoming available to older children in some areas of the globe, as well as prior to the emergence of certain disease variants, including delta, which are responsible for the new surge and have become a major global concern.

A “humanized” mouse model equipped with the immune system of a patient who needs an organ transplant beats current measures for identifying the best potential living donor, scientists report.
They call the new approach an “immunobiological algorithm” that provides a comprehensive prospective on how a patient’s immune system will react to tissue from each potential living donor, says Dr. Anatolij Horuzsko, immunologist at the Medical College of Georgia and Georgia Cancer Center.
The current standard, HLA, or human leukocyte antigen, testing is used to compare a potential recipient and donor’s lineup of a handful of proteins on the surface of their cells that provide cues to how aggressively the recipient’s immune system is likely to respond to the new organ.
Scientists did a head on comparison of the two approaches in a study published in the journal Frontiers in Immunology and the best donor identified per HLA testing ultimately triggered the strongest immune response, which translates to an increased risk for organ rejection and the need for more medication to try to keep that immune response at bay.
“We create a situation very close to reality with a kidney transplant or any type of organ transplant,” says corresponding author Horuzsko. “We see the response of T cells, CD8+ T cells, killer cells, many factors which potentially have a killing effect on the transplanted kidney,” he says, noting the comprehensive assessment shows the response of antigens that have not even been named, but whose collective immune response is clear.
“That’s the beauty of this,” says Dr. Laura Mulloy, chief of the MCG Division of Nephrology, Horuzsko’s longtime collaborator and a coauthor on the new paper. “It’s more comprehensive, specific testing.”
Our blood contains all the components of the immune system, and to build the model of a patient’s immune system, Horuzsko’s team, which developed this system from scratch over the past five years, isolates those components, which are given to a mouse without an immune system. A humanized mouse model is created for each potential donor, each potential donor’s blood is then given to the mouse and the varying immune responses measured. An additional model is given the patient’s own blood as a control.

SharecloseShare pageCopy linkAbout sharingimage sourceGetty ImagesHealth officials are urging festival-goers this weekend to take a free rapid Covid test before they attend, stay outside and apart from other groups as much as possible.Experts say sharing public transport, tents and cars are key trigger points, with outdoor spaces far less risky.There is concern the events, in places like Reading and Leeds, could lead to a rise in cases in young people.All 16 and 17-year-olds have only recently been offered a Covid vaccine.And tens of thousands of them and older teenagers are expect to attend festivals this bank holiday weekend.Dr Susan Hopkins, of Public Health England (PHE), advised youngsters to wear a face covering if using public transport to travel to festivals, and also urged caution when they return home.”You may well have caught Covid-19 while you’ve been away,” she said. “Make sure you take an LFD test when you get home and then test twice a week after having mixed with a large group of people.”Try and avoid seeing older or more vulnerable relatives so that you don’t pass anything on.”Reading Festival will be emotional, says bossVaccine target set for 16 and 17-year-oldsWaning immunity and rising cases – time to worry? Meradin Peachey, director of public health for west Berkshire, which covers Reading, said: “Sixteen, 17-year-olds are the main groups that are going to be there and they’re not covered yet.”We are trying to ask people to show proof of a lateral flow test before you even get anywhere near the gates.”The Boardmasters Festival in Cornwall earlier this month, which attracted about 50,000 people, is thought to have created 4,700 coronavirus cases.But council leaders in the county, which has some of highest case rates in England, say there is no reason to cancel any holiday events this weekend.Cases climbingIt comes as infections in the UK are climbing again to about 34,000 cases reported every day in the past week – a similar number reported daily in mid-January around the winter peak.But the number of people admitted to hospital and dying with Covid is far below the levels seen then because of high levels of protection from the vaccines.The Office for National Statistics estimates that infection rates have increased across all four UK nations in the week up to 20 August, with stark variations.The number of people thought to be infected is:one in 40 in Northern Irelandone in 70 in Englandone in 120 in Walesone in 140 in Scotland Dr Michael Head, from the University of Southampton, said the main trigger points at mass gatherings were indoor settings.”Where festival-goers are in a field, even in large numbers, the transmission risks will remain relatively low. “It is the indoor shared spaces that are key, such as marquees, tents, or shared cars, and use of public transport to and from the event.”He said using masks would be helpful, and everyone should have a Covid-19 vaccine when offered one.Dr Julian Tang, clinical virologist at the University of Leicester, said people needed to make their own assessments of risk.But he said “these are admittedly very difficult to make accurately without knowing your vaccine responses, those of others, as well as what viral loads people around you might be shedding at any point – and then your individual susceptibility to more severe or long-Covid complications”.Ambulance pleaThe London Ambulance Service is also asking people to use its services wisely this weekend as it prepares for a busy bank holiday, which could be “what we normally see on New Year’s Eve”, it said.The service puts the extra demand down to increased spread of Covid in the community, more people being out and about, and travelling in and out of the capital.It said August was expected to be one of the busiest months ever for the service.Alicia Demirjian, incident director for Covid-19 at Public Health England (PHE), said: “Cases of Covid-19 are still high, especially among young people. “If you have Covid-19 symptoms, please do not go out – stay at home and get a PCR test as soon as possible.”If you are heading to a festival or other event this bank holiday weekend, to protect your friends and others we encourage you to take a free rapid test before you leave to check that you do not have the virus.” PHE said it would be closely monitoring how the start of the school term, which is happening for many children next week in England, affects the number of new infections.

During the Delta surge, British schools emphasized other safety measures: quarantining and regular testing for the virus.From late spring into early summer, Britain’s elementary and secondary schools were open during an alarming wave of Delta infections.And they handled the Delta spike in ways that might surprise American parents, educators and lawmakers: Masking was a limited part of the strategy. In fact, for the most part, elementary school students and their teachers did not wear them in classrooms at all.Instead, the British government focused on other safety measures, widespread quarantining and rapid testing.“The U.K. has always, from the beginning, emphasized they do not see a place for face coverings for children if it’s avoidable,” said Dr. Shamez Ladhani, a pediatric infectious-disease specialist at St. George’s Hospital in London and an author of several government studies on the virus and schools.The potential harms exceed the potential benefits, he said, because seeing faces is “important for the social development and interaction between people.”The British school system is different than the American one. But with school systems all over the United States debating whether to require masking, Britain’s experience during the Delta surge does show what happened in a country that relied on another safety measure — quarantining — rather than face coverings for young children.Unlike the United States, all public and private schools in England are expected to follow the national government’s virus mandates, and there is a single set of guidelines. (Scotland, Wales and Northern Ireland are responsible for their own schools, but the rules have been similar.)The Delta variant tested the guidelines. Starting in June, case numbers quickly increased before peaking in mid-July, which roughly mirrors the last few months of the school calendar. For the 13 million people in England under the age of 20, daily virus cases rose from about 600 in mid-May to 12,000 in mid-July, according to government data. Test positivity rates were highest among children and young adults — ages 5 to 24 — but they were also the least likely to be vaccinated.It is difficult to pinpoint exactly how much spread occurred on campuses. But throughout the pandemic, government studies showed that infection rates in schools did not exceed those in the community at large, Dr. Ladhani said. In schools that experienced multiple virus cases, he added, there were often “multiple introductions” — meaning that infections were likely acquired outside the building.There is debate about whether the end of the school year in mid-July contributed to the nation’s drop in virus cases, but some researchers point out that the decline began before schools closed.To counter the Delta variant during the last academic year, the government provided free rapid tests to families and asked them to test their children at home twice per week, though compliance was spotty. Students were kept in groups within the school building and sent home for 10-day quarantines if a virus case was confirmed within the bubble. More than 90 percent of school staff members had received at least one vaccine dose by the end of June, according to a government sample survey of English schools, a similar vaccination rate to American teachers in the Northeast and West, but higher than in the South.Under the government guidelines, masks in classrooms were required only for discrete periods in secondary schools, the equivalent of middle and high school, and were never required for elementary-age children.Students waiting for coronavirus vaccines in London. More than 90 percent of school staff members in Britain had received at least one vaccine dose by the end of June.Daniel Leal-Olivas/Agence France-Presse — Getty ImagesAnd there was less partisan divide; both the Conservative and Labour Parties have generally believed that face coverings hinder young children’s ability to communicate, socialize and learn.In England, schools followed government recommendations last academic year and aggressively quarantined students and staff who came into contact with the virus.But quarantines were disruptive for students and parents and led, in mid-July, to more than 1 million children being forced out of schools, or 14 percent of the public school population. During the same period, about 7 percent of teachers were sent home.Rudo Manokore-Addy, the mother of a 7-year-old and 3-year-old in London, described herself as more cautious when it came to the virus than the typical British parent. In the spring of 2020, she encouraged her daughters to wear cloth masks outside the house. At times last summer and this past winter, she kept both girls home from school to observe the schools’ virus policies before sending her children back.Last spring, during the Delta surge, she and her husband gladly kept their children in school, unmasked.“I was quite relaxed,” she said. “At the end, we just resolved to kind of go with it. We were confident the school had practices in place.”In the United States, the federal Centers for Disease Control and Prevention currently recommends universal masking inside school buildings, and the C.D.C. has advised that breaches in mask use were likely responsible for some spread of Covid-19 in American schools.This recommendation has been divisive, with nine states attempting to ban school mask orders, according to the Center on Reinventing Public Education, a think tank. But with low vaccination rates in many communities and limited access to regular virus testing across the country, masking may be one of the easiest safety measures for American schools to put into place. In addition, the C.D.C. has said that students who come into contact with the virus in schools do not need to quarantine if both individuals wore well-fitting masks.The American conversation on masks is “so polarized,” said Alasdair Munro, a pediatric infectious-disease researcher at the University Hospital Southampton. “It seems to either be viewed as an essential, nonnegotiable imperative or a very harmful infringement upon individual liberty.”Others in Britain would welcome masking. Dr. Deepti Gurdasani, an epidemiologist and senior lecturer at Queen Mary University of London, has spoken widely for stricter safety precautions in schools. She called the British government’s opposition to masking among children “ideological,” and said she looked with envy at the New York City school system’s policies around universal masking and the placement of two air purifiers in each classroom.But there has also been quarantining in the United States, with some schools that have reopened for the new academic year temporarily closing classrooms over the past several weeks.Research from Britain suggests that rapid testing might be an alternative. In a study conducted as the Delta variant spread, secondary schools and colleges in England were randomly assigned to quarantine or test.One set of schools quarantined students and staff members who came into contact with positive Covid-19 cases. The other allowed those contacts to continue coming into the building, but with the requirement that they take a rapid virus test each day for one week; only those who tested positive would be sent home.Though the daily testing regimen was challenging for some schools to carry out, the results were reassuring: In both the quarantine and test groups, less than 2 percent of the contacts tested positive for Covid-19.Health workers at a virus testing site in London in May, before the Delta variant began surging throughout the country.Adrian Dennis/Agence France-Presse — Getty ImagesFurther reassuring evidence comes from testing antibodies of school staff members; positivity rates were the same or lower than adults in the community, suggesting that schools were not “hubs of infection,” according to Public Health England, a government agency.Today, after long periods of shuttered classrooms, there is now a broad consensus in Britain that policies that keep children out of school are “extremely harmful in the long term,” Dr. Munro said.The national Department for Education also announced last week that in the coming school year, no one under the age of 18 would be forced to quarantine after contact with a positive virus case, regardless of vaccination status. (In Britain, vaccines are approved for individuals 16 and over.)Masks will not be required for any students or school staff, though they will be recommended in “enclosed and crowded spaces where you may come into contact with people you don’t normally meet,” such as public transit to and from school.Some critics believe that the British government has been too quick to loosen safety measures inside schools.Dr. Gurdasani said the lack of precautions this fall would increase the number of children infected and suffering the effects of long Covid.“I am not advocating for school closures,” she said. “But I don’t want a generation of children disabled in the coming years.”Robin Bevan, president of the National Education Union and a secondary school principal in Southend, east of London, said he found it curious that Britons regularly masked in supermarkets, but not in schools.“All we are left with is opening the windows and washing hands,” he said. “That is the government position.”School leaders have the latitude to continue to keep children in defined bubbles or pods to reduce transmission — a practice Mr. Bevan said he would like to keep.Many parents say they are keeping calm.“It felt like in the U.K., there was such political commitment to reopening,” said Bethan Roberts, 40, who felt confident returning her three children to in-person learning last spring and keeping them there during the Delta surge.“It didn’t feel very controversial here,” she added. “And there were lots of exhausted parents who were just, like, ‘We can’t do this anymore.’”Alicia Parlapiano