| Title: |
P-1435. Effectiveness of RSV Immunization among Infants in Their First RSV Season in the United States, 2023-2024 and 2024-2025 Seasons |
| Authors: |
Payne, Amanda B.; Battan-Wraith, Steph; Reese, Sarah E.; Hathaway, Cassandra A.; Tartof, Sara Y.; Natarajan, Karthik; Irving, Stephanie; Grannis, Shaun J.; Chickery, Sean M.; Vazquez-Benitez, Gabriela; Dascomb, Kristin K.; Salas, S. Bianca; Bezi, Cassandra; Sy, Lina S.; Lewin, Bruno; Stockwell, Melissa S.; Stephens, Ashley B.; Han, Jungmi; Naleway, Allison L.; Dixon, Brian E.; Rogerson, Colin; Duszynski, Thomas; Fadel, William F.; Ball, Sarah W.; Cao, Jingran; McEvoy, Charlene E.; Sheffield, Tamara; Bride, Daniel; Arndorfer, Julie; Van Otterloo, Joshua; Kautz, Amber; Avrich Ciesla, Allison; Najdowski, Morgan; Mak, Josephine; DeCuir, Jennifer; Wiegand, Ryan E.; Link-Gelles, Ruth |
| Contributors: |
Health Policy and Management, Richard M. Fairbanks School of Public Health |
| Source: |
PMC |
| Publisher Information: |
Oxford University Press |
| Publication Year: |
2026 |
| Collection: |
Indiana University - Purdue University Indianapolis: IUPUI Scholar Works |
| Subject Terms: |
Respiratory syncytial virus (RSV); Maternal vaccine; Infant monoclonal antibody; Infants |
| Description: |
Background: During the 2023-2024 and 2024-2025 respiratory virus seasons, two products, a maternal vaccine (Abrysvo, by Pfizer) and an infant monoclonal antibody (nirsevimab), were recommended in the United States to protect infants against severe respiratory syncytial virus (RSV) disease during their first RSV season. We estimated product effectiveness (PE) against RSV-associated emergency department (ED) encounters and hospitalizations among infants in their first RSV season during these seasons. Methods: VISION includes integrated health record data with linkages to state and local immunization information systems from 127 EDs and 107 hospitals. We conducted a test-negative analysis using data from 6 VISION sites, including children with ED encounters and hospitalizations with a diagnosis of RSV-like illness (RLI) during October 2023–March 2024 and October 2024–March 2025 among infants in their first RSV season. PE was estimated for each product, comparing the odds of immunization versus no immunization among RSV-positive cases and RSV-negative controls, adjusting for age, race and ethnicity, sex, calendar day, and geographic region. Results: Of the 8,404 RLI ED encounters and 1,395 RLI hospitalizations among infants in their first RSV season without exposure to maternal RSV vaccine, 2,981 (35%) and 771 (55%) were RSV-positive and 1,448 (17%) and 208 (15%) had evidence of nirsevimab receipt, respectively. Nirsevimab effectiveness was 67% (95% CI: 61-72%) against RSV-associated ED encounters and 92% (95% CI: 87-95%) against RSV-associated hospitalization (Table 1). In 1,508 RLI ED encounters and 421 RLI hospitalizations among infants in their first RSV season without receipt of nirsevimab, 480 (32%) and 222 (53%) were RSV-positive and 261 (17%) and 62 (15%) had evidence of maternal RSV vaccination, respectively. Maternal RSV vaccine PE was 70% (95% CI: 57-79%) against RSV-associated ED encounters and 79% (95% CI: 58-89%) against RSV-associated hospitalization among infants in their first RSV season (Table 2). ... |
| Document Type: |
article in journal/newspaper |
| File Description: |
application/pdf |
| Language: |
English |
| Relation: |
Open Forum Infectious Diseases; https://hdl.handle.net/1805/53873 |
| Availability: |
https://hdl.handle.net/1805/53873 |
| Rights: |
Attribution 4.0 International ; http://creativecommons.org/licenses/by/4.0/ |
| Accession Number: |
edsbas.88BA58D2 |
| Database: |
BASE |