New WHO Recommendations to Protect Infants from RSV
The World Health Organization recently published its first-ever position paper outlining recommendations to protect infants against respiratory syncytial virus (RSV), the leading cause of acute lower respiratory infections in children. These recommendations are the first step toward increasing access to lifesaving RSV immunization products around the world.
RSV is responsible for approximately , with nearly all (97%) of these deaths occurring in low- and middle-income countries (LMICs). A of more than 9,000 children in seven LMICs across Africa and Asia found that RSV accounted for 31% of cases of severe pneumonia requiring hospitalization. Forthcoming results from a recent systematic review demonstrate that across WHO regions, RSV caused 24% to 37% of acute respiratory illness among hospitalized children younger than 5 years. The proportion was twice as high among infants under 6 months (41%) compared to older children (19%).
As there is no specific treatment for RSV, preventive measures are critical to reduce disease burden among infants. This includes both protecting infants directly with long-acting monoclonal antibodies as well as passive immunization with a maternal vaccine, as infants can benefit from transplacental transfer of their mothers’ RSV antibodies for approximately 6 months after birth. Importantly,
WHO has that all countries introduce products to prevent severe RSV disease among young infants. Specifics of these recommendations include:
- For countries choosing to implement maternal vaccination, a single dose of RSV vaccine should be administered during the third trimester, ideally at least 2 weeks before delivery. This timing allows countries to link RSV vaccination with other antenatal care recommendations during the third trimester while also allowing sufficient time for antibody transfer.
- For countries choosing to introduce monoclonal antibodies, a single dose should be administered at birth or at the earliest opportunity. Although infants younger than 6 months will benefit most, countries may choose to administer monoclonal antibodies to infants up to 12 months who are entering their first RSV season.
- In countries in tropical or subtropical regions, where RSV circulates throughout the year, a year-round approach to RSV immunization will most likely be more feasible and cost-effective. In countries with established seasonal patterns of RSV transmission, a seasonal immunization approach can be considered.
- Generally, the same mother-infant pair should not receive both maternal vaccination and a monoclonal antibody.
“The high burden of severe RSV disease among young infants and the fact that, as a virus, it is not treatable with antibiotics, makes prevention all the more important,” said Maria Deloria Knoll, IVAC’s Director of Epidemiology and a Research Professor in the Department of International Health. “The new WHO recommendation is good news for children, their families and caregivers.” However, she cautioned that that affordability and feasibility of implementation of these products may be a challenge for some countries. We must work to ensure that products to prevent RSV are accessible to those infants who are most vulnerable to severe disease in all parts of the world.
