WHO Recommends Vaccines to Curb RSV in Infants Globally

WHO Recommends Vaccines to Curb RSV in Infants Globally

New Delhi: The World Health Organization (WHO) has made a significant breakthrough in the fight against respiratory syncytial virus (RSV), a leading cause of severe respiratory infections in children worldwide. On Friday, WHO urged all countries to adopt both a maternal vaccine and a monoclonal antibody to protect infants from this potentially deadly virus.

The maternal vaccine, known as RSVpreF, is intended for administration to pregnant women during their third trimester, ensuring protective antibodies are passed on to the newborn. Complementing this, the monoclonal antibody nirsevimab can be administered to infants starting from birth, ideally just before or during the RSV season.

According to WHO estimates, RSV results in approximately 100,000 deaths and over 3.6 million hospitalizations in children under five each year. Alarmingly, about half of these fatalities occur in infants younger than six months. Moreover, 97 percent of these deaths happen in low- and middle-income countries where access to critical medical care, such as oxygen therapy and hydration support, is scarce.

While the symptoms of RSV often mimic those of the common cold, such as runny nose and cough, the virus can lead to severe complications, including pneumonia and bronchiolitis, especially in vulnerable populations including infants, young children, older adults, and individuals with weakened immune systems.

Both RSVpreF and nirsevimab received endorsements from the Strategic Advisory Group of Experts on Immunisation (SAGE) for global rollout, scheduled for implementation in September 2024. Furthermore, the maternal vaccine was prequalified by WHO in March 2025, facilitating its procurement by UN agencies.

The administration schedule for these vaccines is designed to maximize their effectiveness. The maternal vaccine can be included as part of routine antenatal care, while nirsevimab is delivered as a single injection that begins to provide protection against RSV within a week and can last for at least five months, covering the entire RSV season in applicable regions.

The WHO recommends that infants receive nirsevimab ideally at birth or before they are discharged from the maternity ward. Alternatively, if not given immediately after birth, the monoclonal antibody can be administered at the baby's first health checkup. In cases where countries choose to limit administration to the RSV season, doses can be given to older infants prior to their first RSV season for enhanced immunity.

The most significant positive impact in preventing severe RSV disease is anticipated when the monoclonal antibody is administered to infants under six months of age, with benefits extending to infants up to twelve months as well.

Dr. Kate O’Brien, Director of Immunisation, Vaccines, and Biologicals at WHO, remarked, "RSV is an incredibly infectious virus affecting individuals across all ages but poses particular risks to infants, especially premature babies. The newly recommended immunization products are pivotal in combating severe RSV disease, dramatically reducing hospitalizations and mortality, potentially saving countless young lives worldwide."

Experts in the field have highlighted that the effective administration of RSV vaccines requires meticulous timing and tailored strategies focused on both pregnant women and their infants. Maternal immunization not only enhances the newborn's defense through passive immunity but also emphasizes the need for direct vaccination for infants to fortify their immune systems against RSV. To achieve optimal vaccine efficacy while minimizing potential risks, careful attention to clinical guidelines regarding gestational age, infant health status, and potential interactions with other immunizations becomes imperative.

The proactive strategies outlined by health authorities aim to diminish RSV-related complications among young children who are particularly vulnerable to severe health outcomes linked to this virus.