Service delivery (feasibility)
Both the maternal RSV Pre-F vaccine and the two available mAb products require only a single dose.
Maternal vaccination with the RSV Pre-F vaccine is recommended by WHO for use in the third trimester of pregnancy.
Nirsevimab is available in two weight-band dosages: 50 mg for infants <5 kg and 100 mg for infants ≥ 5 kg. WHO recommends that it be given to infants at birth or soon after if a year-round strategy is adopted. If a seasonal administration strategy is adopted, a single dose is recommended for infants aged up to 12 months, beginning shortly before the start of the RSV season, as well as at birth or the earliest opportunity thereafter for infants born during the RSV season.Go to footnote 1, Go to footnote 2
Clersovimab has one single dosage 105 mg and is recommended to be given to infants at birth or before start of the RSV season.Go to footnote 3 It has been recommended for use for the protection of infants up to 12 months of age in a few countries.Go to footnote 4, Go to footnote 5 As of August 2026, WHO has not yet reviewed the evidence in order to issue formal recommendations on the use of clesrovimab.
- Go back to footnote reference 1
World Health Organization (2025). WHO position paper on immunization to protect infants against respiratory syncytial virus disease, May 2025 Weekly Epidemiological Record. 2025;100(22):193-218 (https://www.who.int/publications/i/item/WER10022, accessed 28 June 2026).
- Go back to footnote reference 2
World Health Organization (2024). Meeting of the Strategic Advisory Group of Experts on Immunization (SAGE), December 2024. Wkly Epidemiol Rec. 99(49):719–40 (https://www.who.int/publications/i/item/who-wer9949-719-740, accessed 28 June 2026).
- Go back to footnote reference 3
Enflonsia (clesrovimab) . European Medicines Agency; 2026 (https://www.ema.europa.eu/en/medicines/human/EPAR/enflonsia, accessed 17 August 2026).
- Go back to footnote reference 4
Killikelly A, Siu W, Brousseau N. Summary of the National Advisory Committee on Immunization (NACI) Statement: Updated guidance to protect infants and children from respiratory syncytial virus disease. Can Commun Dis Rep. 2026;52(6):223-6. doi:10.14745/ccdr.v52i06a01.
- Go back to footnote reference 5
Moulia DL, Link-Gelles R, Chu HY, Jamieson D, Brooks O, et al. Use of Clesrovimab for Prevention of Severe Respiratory Syncytial Virus-Associated Lower Respiratory Tract Infections in Infants: Recommendations of the Advisory Committee on Immunization Practices - United States, 2025. MMWR Morb Mortal Wkly Rep. 2025;74(32):508-14. doi:10.15585/mmwr.mm7432a3.
