Maternal Respiratory Syncytial Virus Vaccination and Receipt of Respiratory Syncytial Virus Antibody (Nirsevimab) by Infants Aged <8 Months - United States, April 2024

Abstract

Respiratory syncytial virus (RSV) is the most common cause of hospitalization among U.S. infants. CDC recommends RSV vaccination for pregnant persons or administration of RSV antibody (nirsevimab) to infants aged <8 months to prevent RSV lower respiratory tract disease among infants. To determine maternal and infant RSV immunization coverage for the 2023-24 RSV season, CDC conducted an Internet panel survey during March 26-April 11, 2024. Among 678 women at 32-36 weeks' gestation during September 2023-January 2024, 32.6% reported receipt of an RSV vaccine any time during pregnancy. Among 866 women with an infant born during August 2023-March 2024, 44.6% reported receipt of nirsevimab by the infant. Overall, 55.8% of infants were protected by maternal RSV vaccine, nirsevimab, or both. Provider recommendation for maternal vaccination or infant nirsevimab was associated with higher immunization coverage, whereas lack of a provider recommendation was the main reason for not getting RSV immunization. The main reason for definitely or probably not getting nirsevimab for infants was concern about the long-term safety for the infant. Activities supporting providers to make RSV prevention recommendations and have informative conversations with patients might increase the proportion of infants protected against severe RSV disease. CDC and the American College of Obstetricians and Gynecologists have resources to assist providers in effectively communicating the importance of immunization.

FIGURE

Main reason for not receiving respiratory syncytial virus vaccine among unvaccinated pregnant or recently pregnant women (N = 433) (A) and probably or definitely not receiving respiratory syncytial virus antibody (nirsevimab) for unprotected infants (N = 240) (B)^, — Internet panel survey, United States, April 2024 Abbreviations: RSV = respiratory syncytial virus; Tdap = tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine. * Currently or recently pregnant women with a live birth who were 32–36 gestational weeks pregnant any time during September 1, 2023–January 31, 2024, and were not vaccinated against RSV during their pregnancy, were asked to select from a list of reasons for not receiving a maternal RSV vaccine (among the 446 unvaccinated women, 11 recently pregnant women who did not report a live birth were not asked the question, and two did not respond to the question, leaving a sample size of 433). Respondents who selected more than one reason were asked to select the main reason. Reasons reported by <2% of respondents are not shown. ^† Currently pregnant women who were not vaccinated against RSV, and recently pregnant women with a live birth, who reported their infants had not received nirsevimab and would “definitely” or “probably” not receive nirsevimab, were asked to select from a list of reasons why their infant would “definitely” or “probably” not receive nirsevimab. Respondents who selected more than one reason were asked to select the main reason. Reasons reported by <2% of respondents are not shown. ^§ Estimates for the responses “An RSV antibody shot would not work very well at preventing RSV for my baby” and “I am concerned about the short-term safety of an RSV antibody shot for my baby” do not meet the National Center for Health Statistics’ standards of reliability and should be interpreted with caution. https://www.cdc.gov/nchs/data/series/sr_02/sr02_175.pdf