The American Academy of Pediatrics (AAP) has released recommendations for childhood vaccination against respiratory syncytial virus (RSV) for the 2026-2027 season.

The American Academy of Pediatrics has updated its recommendations for the prevention of respiratory syncytial virus infection for the 2026-2027 season. The major change concerns children aged 8-19 months entering the second season of the virus's circulation: the list of conditions for which prophylactic administration of the long-acting monoclonal antibody nirsevimab is recommended has been significantly expanded. It now includes certain extremely premature infants, children with hemodynamically significant congenital heart defects, certain respiratory and neuromuscular diseases, as well as Down syndrome and certain other chromosomal abnormalities.

The strategy for the first season has not changed fundamentally. The American Academy of Pediatrics continues to recommend protection for all infants under 8 months of age who are born during the RSV season or are entering their first season, unless they have documented protection from maternal vaccination. After birth, prophylaxis is administered with a single dose of a long-acting monoclonal antibody—nirsevimab or clesrovimab.

The update was based not only on clinical trials of the drugs but also on several seasons of their actual use. For example, in the US surveillance system, the efficacy of nirsevimab against RSV-related hospitalization in the first season was estimated at approximately 90%, while in another study, it was 98%. A separate analysis of severe cases showed approximately 80% efficacy against intensive care unit admission and 83% against acute respiratory failure.

However, this new publication is not yet another clinical trial of a specific drug. It is a technical report from the American Academy of Pediatrics' Committee on Infectious Diseases, systematizing data on the epidemiology of RSV, risk groups, efficacy, safety, and cost-effectiveness of prophylaxis. The report is accompanied by a separate policy statement with its own DOI and provides recommendations for the 2026-2027 season.

Key point of the 2026-2027 recommendations	What has changed?
The first season of RSV	protection is still recommended for all infants under 8 months of age without sufficient protection after vaccination during pregnancy
First season drugs	nirsevimab or clesrovimab
Season two	prevention only for children 8-19 months at high risk
The main drug of the second season	nirsevimab
New group	children born before 32 weeks of pregnancy
New group	hemodynamically significant congenital heart defects
New group	anatomical abnormalities of the lungs and certain neuromuscular diseases
New group	Down syndrome and some other chromosomal abnormalities
Previously included groups	severe chronic lung disease of prematurity, severe immunodeficiency, some cases of cystic fibrosis, children of Native Americans and Alaskans
DOI of the technical report	10.1542/peds.2026-079049
DOI official recommendation	10.1542/peds.2026-079047

Why RSV remains a major infectious threat to infants

Respiratory syncytial virus (RSV) is extremely common. Most children become infected before the age of two, with approximately 20-30% of those infected developing lower respiratory tract infections such as bronchiolitis or pneumonia. Reinfection is possible and common, although subsequent infections are usually milder than the first.

The first months of life are especially vulnerable. According to a technical report, RSV causes approximately 58,000-80,000 hospitalizations in children under five in the United States each year, and up to 3% of children may be hospitalized due to RSV in the first year of life. The highest hospitalization rates occur in the first six months after birth.

The disease can be severe even in a child without congenital pathologies. One of the key arguments in favor of universal prophylaxis during the first season is that approximately three-quarters of hospitalized RSV-positive infants under one year of age were previously considered healthy and had neither prematurity nor known chronic diseases. In other words, it is impossible to select only children with obvious risk factors for protection.

The global burden is even higher. It is estimated that approximately 33 million episodes of lower respiratory tract infection (RSV) occur annually in children under five years of age, with 3.6 million hospitalizations and approximately 100,000 deaths. Approximately 97% of childhood deaths occur in low- and middle-income countries, where intensive care and respiratory support capacity is limited.

The scale of the problem

Indicator	Grade
Hospitalizations of children under 5 years old in the United States	58,000-80,000 per year
Hospitalization in the first year of life	up to 3% of children
Children who become infected by age 2	majority
Lower respiratory tract infection among infected persons	20-30%
Worldwide episodes of RSV lower respiratory tract infection	≈33 million per year
Hospitalizations worldwide	≈3.6 million
Child deaths	≈100,000
Deaths in low- and middle-income countries	≈97%

Why are all babies protected in the first season, but not all in the second?

Age significantly affects the risk of severe RSV infection. In the first few months, the airways are small, pulmonary reserves are limited, and the immune system is still developing. Even moderate swelling and secretion accumulation in the bronchioles can quickly lead to severe respiratory failure. Therefore, the first season of infection is the most dangerous for almost any infant.

After the first year of life, the risk of severe illness, on average, decreases sharply. The airways become larger, the immune system has already encountered respiratory viruses, and many children have partial natural immunity after their first RSV infection. This is why administering an expensive monoclonal antibody to all children before the second season has significantly less absolute benefit.

However, some children retain a risk comparable to or even exceeding that of healthy infants in the first year of life. In a Canadian population-based study, the rate of RSV-related hospitalizations in children with chronic conditions during the second season was 7.8 per 1,000 person-years, compared to approximately 8.0 per 1,000 in healthy infants during the first season. In the presence of multisystem chronic diseases, the risk in the second season was more than twice that of healthy infants during the first season.

A particularly revealing analysis of 1,083 hospitalized children aged 12-23 months in the United States is particularly revealing. Approximately 23.4% had at least one chronic condition, and the rate of intensive care unit (ICU) admission increased from 22% with one or no chronic conditions to 30% with two or more. Furthermore, 92% of children with RSV who required intensive care during the second season did not meet the previous prophylaxis criteria. This gap between the old policy and the actual population of severely ill patients became one of the main arguments for expanding the recommendations.

Which children are now considered high-risk for the second season?

Prior to this update, prophylaxis during the second season was already recommended for children with severe chronic lung disease of prematurity who required oxygen, diuretics, or long-term corticosteroid therapy in the previous six months. The list also included children with severe immunodeficiency, certain children with cystic fibrosis, and American Indian and Alaska Native children.

In 2026, all children born before 32 weeks of gestation were added to this category, regardless of whether they required oxygen, medication, or other support at the start of the second season. Children with hemodynamically significant congenital heart defects, that is, defects that cause symptoms or dilation of the heart chambers, were also added.

Another new category includes children with anatomical abnormalities of the airways or neuromuscular diseases that impair coughing, swallowing, or the ability to clear secretions from the airways. This problem can arise with congenital defects of the lungs and trachea, tracheostomy, certain neurological diseases, muscular dystrophies, and other conditions. In studies, children with neurological diseases had a 6-11 times higher rate of RSV-specific hospitalizations than the general pediatric population.

The fourth major expansion concerns Down syndrome and other chromosomal abnormalities that increase the risk of severe RSV infection. Systematic studies have long indicated a high risk in this group. One meta-analysis estimated the relative risk of RSV hospitalization in children with Down syndrome under two years of age to be approximately 6.06 times higher, while another analysis found an odds ratio of hospitalization of approximately 8.69.

The full selection process for the second season

Group 8-19 months	Recommendation
Birth <32 weeks gestation	Yes, a new category
Chronic lung disease of prematurity with recent medical support	Yes
Hemodynamically significant congenital heart defect	Yes, a new category
Anatomical anomaly of the respiratory system with impaired secretion clearance	Yes, a new category
Certain neuromuscular disorders	Yes, a new category
Severe immunodeficiency	Yes
Down syndrome/certain other chromosomal abnormalities	Yes, a new category
Severe cystic fibrosis or weight/length <10th percentile	Yes
American Indians and Alaska Natives	Yes
A healthy child 8-19 months old without risk factors	not routinely

Why is the cutoff for prematurity set at 32 weeks?

The risk of severe RSV infection increases with decreasing gestational age. The reasons are clear: the earlier a baby is born, the less time there is for the maturation of lung tissue and the immune system, and the transfer of maternal antibodies across the placenta. Very premature babies are also more likely to have chronic pulmonary and cardiac problems.

The technical report shows a pronounced hospitalization gradient. For children born before 29 weeks, the RSV hospitalization rate before age two was approximately 24.9 per 1,000, at 29-31 weeks – 19.3 per 1,000, at 32-34 weeks – 17.5, at 35-36 weeks – 11.3, and after 37 weeks – approximately 7.5 per 1,000.

However, for decisions about prophylaxis in the second season, what's more important is not the absolute difference immediately after birth, but whether the additional risk persists after 12 months. Here, studies show a much clearer boundary: among children born before 32 weeks, the hospitalization rate continues to be elevated in the second year, while among those born between 32 and 36 weeks, there is no longer a statistically significant difference from the general population of the same age.

That's why the American Academy of Pediatrics has chosen the practical threshold of "less than 32 weeks, 0 days." Unlike previous criteria, a baby in this category no longer requires continued oxygen or medications: the mere fact of extreme prematurity is considered sufficient evidence of continued risk in the second trimester.

Nirsevimab has already demonstrated high efficacy in real-world practice.

Nirsevimab is a long-acting monoclonal antibody directed against the prefused form of the RSV F protein. Unlike the vaccine, it does not stimulate the child's immune system to produce antibodies on its own, but rather provides ready-made neutralizing molecules. Its half-life is approximately 71 days, allowing a single dose to protect a child throughout most of the flu season.

After registration, the results of randomized trials were confirmed in real-world practice. The US surveillance system estimated the efficacy against RSV hospitalizations during the first season at approximately 90%. Another analysis of six healthcare systems showed a 77% efficacy against emergency department visits and 98% against hospitalizations.

In a large retrospective analysis that included 409,723 infants from more than 1,700 hospitals and 40,000 outpatient facilities, the rate of RSV hospitalization was 0.4% among those who received nirsevimab and 1.2% among those who did not. Results for the most severe outcomes were particularly important: efficacy against intensive care unit admission was estimated at 80%, and against acute respiratory failure at 83%.

Data has also emerged outside the US. In Galicia, a universal nirsevimab program demonstrated approximately 82% efficacy against hospitalization due to RSV lower respiratory tract infection and 86.9% against severe disease requiring oxygen. A later analysis found an 85.9% reduction in RSV hospitalizations in the first season; some residual effect persisted in the second season, although it was weaker and assessed with greater statistical uncertainty.

The real effectiveness of nirsevimab

Exodus	Evaluation of effectiveness
Hospitalization, American surveillance system	90%
Seeking emergency care	77%
Hospitalization in another US analysis	98%
Admission to the intensive care unit	80%
Acute respiratory failure	83%
Hospitalization in Galicia	82.0%
Severe infection requiring oxygen in Galicia	86.9%
RSV hospitalization in high-risk children during the second season in individual studies	approximately 79-88%

For the second season, the evidence base is smaller, but the risk is concentrated in chronically ill children.

In the second season, the evidence is naturally weaker because the absolute incidence of severe disease is significantly lower. In a study of American Indian and Alaska Native children, the efficacy of nirsevimab against RSV requiring medical attention in the second season was estimated at approximately 88%, and against hospitalization at approximately 87.9%. Confidence intervals were wide due to the small sample size.

A European multicenter study of children under two years of age demonstrated a pooled prophylactic efficacy of approximately 79% against hospitalization with severe respiratory infection, although the results for the second season cannot be completely separated from those for the first. Therefore, the Academy relied not on a single trial, but on the combined risk and efficacy data.

Population-based data from Quebec proved particularly compelling. Among children under 19 months with chronic lung disease, heart defects, pulmonary hypertension, Down syndrome, cystic fibrosis, neuromuscular diseases, or transplant recipients, the adjusted efficacy of nirsevimab was 86% against emergency department visits and 79% against hospitalization.

Thus, expanding the recommendations does not mean that the second season has suddenly become as dangerous for all children as the first. On the contrary, the new approach is more targeted: universal prevention remains the rule for the first season, while in the second, protection is focused on children who remain at high risk.

Klesrovimab provides a second option for first-season protection

Since 2025, American pediatricians have had another long-acting drug available: clesrovimab. Like nirsevimab, it is a monoclonal antibody against RSV and is intended for a single intramuscular injection before or during the first season. Its half-life is approximately 44 days.

In a phase III study involving 3,614 infants—2,412 received clesrovimab and 1,202 received placebo—the efficacy against RSV lower respiratory tract infection requiring medical attention was 60.4%. The efficacy against hospitalization was significantly higher at 84.2%, which is particularly important, as the primary goal of prophylaxis is not so much to completely prevent any infection as to reduce severe outcomes.

For infants in their first season, the American Academy of Pediatrics does not recommend nirsevimab or clesrovimab as a treatment option if the drug is appropriate for the child's age and clinical condition. The clesrovimab dosage for the first season is 105 mg as a single dose, while nirsevimab is administered at a dose of 50 mg for infants weighing less than 5 kg or 100 mg for infants weighing 5 kg or more.

The situation is different for the second season. Although a study of clesrovimab in high-risk children is already yielding encouraging results and the manufacturer has submitted documents for an indication expansion, at the time of publication of the technical report, clesrovimab was not approved in the US for the second season. Therefore, the current recommendation for children aged 8-19 months in high-risk groups applies to nirsevimab.

Comparison of two long-acting antibodies

Characteristic	Nirsevimab	Klesrovimab
First season	Yes	Yes
Age	<8 months	<8 months
One dose	Yes	Yes
Dose for the first season	50 or 100 mg by weight	105 mg
Season two	yes, in high-risk groups	there is no approved indication yet
Dose in the second season	200 mg	-
Half-life	≈71 days	≈44 days
Does the AAP prefer one drug?	no, for the first season	no, for the first season

Monoclonal antibody for infants or vaccine during pregnancy: two strategies, not double protection for everyone

The first RSV season can currently be prevented in two fundamentally different ways. The first is vaccination of the pregnant woman with a prefused F-protein vaccine between the 32nd and 36th weeks of pregnancy. The pregnant woman's body produces its own antibodies, which then cross the placenta and protect the newborn for a short time.

The second option is to administer nirsevimab or clesrovimab to the baby after birth. In this case, there's no need to build immunity: the baby immediately receives ready-made antibodies. The American Academy of Pediatrics doesn't state that one strategy is inherently preferable to the other for most families. The choice depends on the gestational age, the season, drug availability, and parental preference.

Typically, both strategies are not necessary simultaneously. If a pregnant woman received the vaccine early enough—at least 14 days before delivery, as per the current schedule—most infants under eight months do not require an additional monoclonal antibody. If the vaccine was not administered, the status is unknown, or the baby was born too soon after vaccination, then protection of the infant itself is recommended.

There are some exceptions when an additional dose of antibodies may be necessary even after vaccination during pregnancy. For example, procedures that can remove circulating antibodies—plasmapheresis, cardiopulmonary bypass, or extracorporeal membrane oxygenation—can significantly reduce the protection provided. In such situations, the technical report suggests the possibility of re-administering the antibody.

The safety of nirsevimab is no longer confirmed only by clinical trials

In randomized trials of nirsevimab, the rate of serious adverse events was comparable to placebo—6.8% versus 7.3%—and independent investigators did not attribute any deaths or serious events to the drug. Trials in high-risk children also showed a safety profile similar to the previous drug, palivizumab.

Data from post-mass rollout are particularly valuable. In Spain, nirsevimab coverage reached 91.9% in the 2023-2024 season. The pharmacovigilance system recorded 67 reports of 141 suspected adverse events, corresponding to approximately 23.1 reports per 100,000 doses. The most frequently reported were rash, fever, and suspected insufficient drug effect; no serious new safety signals were identified.

A Canadian study of 1,559 children also found no anaphylaxis. Injection site reactions were reported in approximately 9%, and events that interfered with daily activities or required medical attention occurred in 3.4% of children after nirsevimab alone and in 4.2% after concomitant administration with another vaccine.

Results for clesrovimab also look favorable. In a large study, serious adverse events were observed in 11.5% of those receiving the drug and 12.4% of those receiving placebo. Mortality rates were virtually identical, and no deaths were considered drug-related. Data from the second season have also not yet revealed any new safety signals.

What is known about safety

Indicator	Observation
Nirsevimab: Serious events in trials	6.8% versus 7.3% placebo
Spain: Reports of alleged reactions	23.1 per 100,000 doses
Anaphylaxis in Canadian surveillance	not registered
Klesrovimab: Serious Events	11.5% versus 12.4% placebo
New safety signal for season two	not identified
Main contraindication	severe allergic reaction to the drug or its components

Antibodies can be administered simultaneously with regular childhood vaccines

The American Academy of Pediatrics permits the simultaneous administration of RSV monoclonal antibodies with routine vaccines appropriate for the child's age. This is important for practical purposes: families do not need to reschedule routine vaccinations or arrange additional clinic visits just because of nirsevimab or clesrovimab.

In clinical trials, some children received standard vaccinations for seven or fourteen days after nirsevimab. No significant new safety signals were detected. Fever was slightly more common among infants who received the vaccine within two weeks of nirsevimab—1.5% versus 0.7%—but no serious problems related to the combination of interventions were identified.

Biologically, this combination also makes perfect sense. Nirsevimab and clesrovimab are ready-made antibodies that highly specifically bind the RSV viral protein. They do not suppress the immune system as a whole and therefore should not interfere with the immune response to diphtheria, tetanus, whooping cough, polio, or other standard childhood vaccines.

This once again highlights an important terminological distinction. The American Academy of Pediatrics' guidelines use the generic term "RSV immunization," but nirsevimab and clesrovimab are not vaccines. A vaccine trains the immune system to create immune memory, whereas a monoclonal antibody provides temporary passive protection with a pre-made molecule.

When exactly should prevention be carried out?

For most of the continental United States, the Academy recommends administering monoclonal antibodies between October and March. This is consistent with the typical seasonal pattern of RSV, which begins actively circulating in the fall, peaks in the winter, and gradually declines in the spring. However, the timing may be adjusted based on local surveillance.

This clarification is especially relevant after the 2025-2026 flu season. Then, the peak in pediatric hospitalizations in the US occurred unusually late—only in late February—and reached approximately 6.5 hospitalizations per 100,000 children under 18 per week. Due to the prolonged flu season, almost all states extended preventive measures until the end of April.

If a child is born just before the RSV season or during active RSV circulation, prophylaxis is recommended during the first week of life, preferably in the maternity hospital. If the hospital is unable to administer the drug, it should be administered as soon as possible after discharge as an outpatient.

A child born outside the season and less than eight months old by the start of the following season should receive the antibody shortly before the expected RSV surge or as soon as possible after its onset. A previous RSV infection does not guarantee complete protection: reinfection is possible even within the same season. Therefore, a previous infection alone does not cancel the prophylactic recommendation for a child who remains a suitable candidate based on age and risk.

Why the Academy does not recommend nirsevimab for all children in their second year of life

Cost and absolute risk matter. According to calculations by American experts, prophylaxis of infants with nirsevimab during the first season, at an estimated cost of $445 per dose, equates to approximately $102,811 per additional quality-adjusted life-year. For the US healthcare system, this is roughly within the range often considered acceptable for effective prophylaxis.

If nirsevimab were administered prophylactically to all children before the second season, when the average risk was significantly lower, the estimated cost would increase to approximately $1.56 million per additional quality-adjusted life-year. This is one argument against universal booster dosing.

This is why the 2026 expansion does not represent a transition from selective prophylaxis to mass booster immunization. The Academy sought to more precisely identify children whose risk in the second season remains so high that the potential absolute benefit of a single dose remains significant. New data on extreme prematurity, congenital heart defects, Down syndrome, and severe airway clearance disorders allowed for the expansion of this group.

However, economic evaluation is not the only criterion for the recommendation. The authors specifically note that disease severity, effectiveness, safety, accessibility, and equity of prevention are also taken into account. A good example is American Indian and Alaska Native children, where the RSV hospitalization rate in some regions was more than double the US average due to a combination of medical and social factors.

Why were Native American and Alaskan children left out of the recommendations?

Before the advent of modern preventive measures, the rate of RSV hospitalizations among American Indian infants in the southwestern United States was approximately 59.6 per 1,000, and among children in the Yukon-Kuskokwim Delta region of Alaska, it was 52.8 per 1,000. By comparison, the average rate for American infants was approximately 22.3 per 1,000.

The authors emphasize that this difference cannot be explained simply by biological or ethnic predisposition. Social conditions play a significant role: distance to medical care, transportation problems, lack of running water in some homes, overcrowded living conditions, and indoor air pollution.

Therefore, this entire population remains in the high-risk category for the second season. Moreover, real-world studies in these communities have already demonstrated the high efficacy of nirsevimab: approximately 86-89% against hospitalization in the first season and approximately 88% against medically significant RSV infection in the second season.

This example illustrates the broader principle of the new recommendations. The risk of severe infection is determined not only by a child's diagnosis but also by the conditions in which they live and receive medical care. However, for most social factors, there are still insufficient precise criteria that could be applied uniformly across all clinics, so the Academy has not created a universal social scale for prescribing nirsevimab.

What the recommendations mean for a child with Down syndrome or a heart defect

For a child aged 8-19 months with Down syndrome entering their second RSV season, the current recommendation differs significantly from the previous approach. Previously, prophylaxis might depend on the presence of an accompanying severe heart defect or another specific indication. Now, Down syndrome itself or another chromosomal disorder associated with an increased risk of severe RSV infection may be grounds for prophylaxis.

The reason lies in a combination of factors: these children are more likely to have congenital heart defects, pulmonary hypertension, airway anatomical features, muscle hypotonia, and immune response disorders. Even in children with Down syndrome without known cardiopulmonary diseases, the risk of hospitalization remained significantly higher than in the general population.

For congenital heart defects, the recommendation is also targeted. Nirsevimab is not indicated for every small atrial septal defect or fully repaired defect in the second season. The Academy specifically notes that children with hemodynamically insignificant defects, successfully repaired defects without ongoing heart failure, and untreated mild cardiomyopathy are generally not considered high-risk for this reason alone.

Therefore, the term "congenital heart disease" should not be taken as an automatic indication. Hemodynamic significance, the presence of heart failure, pulmonary hypertension, drug therapy, and overall clinical risk are crucial; in complex situations, the report recommends an individualized decision in consultation with a pediatric cardiologist.

What remains uncertain for now

Despite the impressive efficacy of modern antibodies, the evidence base is not uniform across all new groups. For healthy infants in the first season, large clinical trials, population-based programs, and hundreds of thousands of real-world observations have accumulated. For some rare conditions, the absolute number of infants studied in the second season is significantly smaller.

Therefore, part of the Academy's decision is based not on a separate large randomized trial for each disease, but on a combination of three types of evidence: how strongly a diagnosis increases the risk of severe RSV infection, how well nirsevimab works in similar high-risk children, and how acceptable its safety profile is. This is typical for recommendations for rare pediatric conditions, where conducting a separate multi-thousand-student trial for each diagnosis is virtually impossible.

The question of clesrovimab in the second season remains. A study in high-risk children shows similar infection and hospitalization rates to the first season, and an application to expand the indication has already been submitted to regulators. However, at the time of publication, approval had not yet been granted, so it is premature to include the drug in the official regimen for the second season.

Finally, the recommendations are focused on the United States and take into account seasonality, approved medications, insurance coverage, and the free childhood vaccine program. Seasonal timing and national programs may vary significantly in other countries. Data on the efficacy of nirsevimab from Spain, Chile, Italy, and other countries support the general preventive principle, but the practical regimen should be consistent with local recommendations.

What's changed since the old palivizumab era?

Before the advent of nirsevimab, the main monoclonal antibody was palivizumab. It was effective, but required monthly intramuscular administration throughout the season—usually five doses. Furthermore, the cost of a single dose in the US was estimated at approximately $1,455–$2,747. Because of this, prophylaxis criteria were deliberately very strict.

Nirsevimab radically changed this logic. A single dose is sufficient to cover a season in most cases, and the estimated cost per dose is approximately $400-500. This allowed for a shift from prophylaxis for only the most severely at-risk groups to universal protection for infants during the first season and broader coverage for high-risk children in their second year of life.

With the advent of clesrovimab, the choice for the first season has become even broader. Palivizumab has now been discontinued in the US, and the Academy does not recommend nirsevimab or clesrovimab as the preferred option if both are suitable for the child. This reflects the shift from complex monthly prophylaxis to simple, single-dose seasonal protection.

The availability of single-dose prophylaxis has effectively redefined the concept of high risk. Some children with Down syndrome, extreme prematurity, or neuromuscular disorders may have previously avoided palivizumab not because the risk was low, but because the balance of cost, evidence, and the need for five injections seemed less favorable. The new drug has changed this balance. [1]

The main conclusion

The main change in the American Academy of Pediatrics' recommendations for the 2026-2027 season concerns the second RSV season. Prophylaxis is still not routinely prescribed for children aged 8-19 months, but the list of high-risk groups has been expanded. It now includes children born before 32 weeks, children with hemodynamically significant heart defects, certain anatomical or neuromuscular respiratory disorders, and Down syndrome or other chromosomal conditions that increase the risk of severe infection.

For infants during the first season, the approach remains universal: virtually all children under eight months should be protected either through antibodies transferred after the mother's vaccination or through a single dose of nirsevimab or clesrovimab. This is because most hospitalized infants were considered completely healthy before their first RSV episode.

Accumulating data confirm the high efficacy of this approach. Nirsevimab, in various studies, reduced the risk of RSV-related hospitalization by approximately 79-98%, and the risk of severe outcomes, including intensive care and respiratory failure, by approximately 80% or more. In a large randomized trial, clesrovimab reduced the risk of RSV-related hospitalization by approximately 84%.

Thus, the 2026 update reflects the transition of pediatric RSV prophylaxis from limited protection for a small number of particularly vulnerable children to a more precise two-stage strategy: universal protection during the first season and targeted protection for children with persistent high risk during the second. It was the real-world data from the first seasons of widespread use of long-acting antibodies that allowed the American Academy of Pediatrics to expand the second stage of this system.

News source

Committee on Infectious Diseases, American Academy of Pediatrics. "Recommendations for the Prevention of Respiratory Syncytial Virus Disease in Infants and Children: Technical Report." Pediatrics, 2026. This document was accepted August 27, 2026, and prepublished September 2, 2026. At this writing, the publisher designates this as a peer-reviewed prepublication that may receive editorial revisions before final publication. DOI for the technical report: 10.1542/peds.2026-079049.

The technical report is accompanied by a separate official statement from the American Academy of Pediatrics with summary recommendations for clinical practice: "Recommendations for the Prevention of RSV Infection in Infants and Children: Official Statement." Pediatrics, 2026. DOI official statement: 10.1542/peds.2026-079047.

Importantly, this publication is not a new clinical trial. It is a technical evidence review and formal guideline update based on randomized trials, surveillance data, real-world effectiveness studies, pharmacovigilance, and analyses of high-risk populations. The American Academy of Pediatrics Committee on Infectious Diseases contributed to the document's development; no external commercial funding was used for the technical report itself.