{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T06:13:22Z","timestamp":1793168002018,"version":"4.5.0"},"reference-count":32,"publisher":"American Academy of Pediatrics (AAP)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,1]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVES<\/jats:title>\n                    <jats:p>To assess the effect of nirsevimab in preventing hospitalizations for lower respiratory tract infection (LRTI) during the second respiratory season of life among infants who were administered nirsevimab in their first months of life.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>Community-based case-control study conducted in 9 tertiary pediatric hospitals in Andalusia, Southern Spain. Infants born between April 1, 2023, and March 31, 2024, were included. Cases were infants hospitalized for LRTI during the 2024 to 2025 season. For each case, 4 community controls were matched by birthdate and province. Exposure was nirsevimab administration during the 2023 to 2024 respiratory syncytial virus (RSV) season. The main outcome was hospitalization for LRTI during the 2024 to 2025 season. Inverse probability weighting (IPW) and doubly robust augmented IPW (AIPW) models were used to estimate the average treatment effect, expressed as absolute risk reduction (ARR).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>The study included 1375 infants (275 cases and 1100 controls). Nirsevimab administration during the 2023 to 2024 season was associated with a 17.0% ARR (95% CI, 3.2%\u201330.8%) in LRTI hospitalizations during the 2024 to 2025 season in the AIPW model. Stronger associations were observed among RSV-positive cases (ARR\u2009=\u200925.4%; 95% CI, 4.9%\u201345.8%) and in infants with a history of inhaler use (ARR\u2009=\u200927.7%; 95% CI, 6.4%\u201348.9%). A negative control exposure (rotavirus vaccination) showed no association, supporting no evidence of relevant residual confounding regarding health-seeking behaviors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>Nirsevimab administration was associated with a reduction in second-season LRTI hospitalizations, suggesting meaningful benefits beyond the season of administration and potential implications for future cost-effectiveness evaluations.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1542\/peds.2025-075562","type":"journal-article","created":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:02:46Z","timestamp":1785196966000},"source":"Crossref","is-referenced-by-count":2,"title":["Nirsevimab and Hospitalization for Lower Respiratory Tract Infection During the Second Season"],"prefix":"10.1542","volume":"158","author":[{"given":"David","family":"Moreno-P\u00e9rez","sequence":"first","affiliation":[{"name":"1Department of Health, Presidency and Emergencies, General Directorate of Public Health and Pharmaceutical Management of Andalusia, Seville, Spain"},{"name":"2Department of Pediatrics at the Malaga Mother-and-Child Hospital, Hospital Regional Universitario de Malaga, Malaga, Spain"},{"name":"3Instituto de Investigaci\u00f3n Biom\u00e9dica de M\u00e1laga (IBIMA), Multidisciplinary Group for Pediatric Research, University of M\u00e1laga, M\u00e1laga, Spain"},{"name":"4Faculty of Medicine, University of M\u00e1laga, M\u00e1laga, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esther","family":"Catal\u00e1n-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"5Service of Preventive Medicine and Public Health, Hospital Universitario de Ja\u00e9n, Ja\u00e9n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Borja","family":"Croche-Santander","sequence":"additional","affiliation":[{"name":"6Service of Pediatrics, Hospital Virgen del Roc\u00edo, Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jes\u00fas Miguel","family":"R\u00edos-Hurtado","sequence":"additional","affiliation":[{"name":"7Service of Pediatrics, Hospital Regional Universitario de M\u00e1laga, M\u00e1laga, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"D\u00edaz-Morales","sequence":"additional","affiliation":[{"name":"8Service of Pediatrics, Hospital Universitario Reina Sofia, C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leticia","family":"Mart\u00ednez-Campos","sequence":"additional","affiliation":[{"name":"9Service of Pediatrics, Pediatric Infectious Diseases Unit, Hospital Materno Infantil Infanta Leonor, Hospital Universitario Torrec\u00e1rdenas, Almer\u00eda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"P\u00e9rez-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"10Service of Pediatrics, Hospital Virgen Macarena, Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda del Carmen","family":"Mart\u00ednez-Padilla","sequence":"additional","affiliation":[{"name":"11Service of Pediatrics, Hospital Universitario de Ja\u00e9n, Ja\u00e9n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Luis","family":"Santos-P\u00e9rez","sequence":"additional","affiliation":[{"name":"12Service of Pediatrics, Hospital Universitario Virgen de las Nieves, Granada, Spain"},{"name":"13Instituto de Investigaci\u00f3n Biosanitaria de Granada (ibs.GRANADA), Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Teresa","family":"Santos-Mart\u00edn","sequence":"additional","affiliation":[{"name":"14Service of Pediatrics, Hospital Universitario Juan Ram\u00f3n Jim\u00e9nez, Huelva, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Estrella","family":"Peromingo-Matute","sequence":"additional","affiliation":[{"name":"15Service of Pediatrics, Hospital Universitario Puerta del Mar, C\u00e1diz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Lorusso","sequence":"additional","affiliation":[{"name":"16Service of Surveillance and Occupational Health, General Directorate of Public Health and Pharmaceutical Regulation, Ministry of Health, Presidency and Emergencies of the Regional Government of Andalusia, Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Rivera-Izquierdo","sequence":"additional","affiliation":[{"name":"13Instituto de Investigaci\u00f3n Biosanitaria de Granada (ibs.GRANADA), Granada, Spain"},{"name":"17Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain"},{"name":"18Centros de Investigaci\u00f3n Biom\u00e9dica en Red de Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"417","published-online":{"date-parts":[[2026,7,28]]},"reference":[{"issue":"22","key":"2026101309121888000_r1","doi-asserted-by":"crossref","first-page":"126030","DOI":"10.1016\/j.vaccine.2024.05.078","article-title":"Effectiveness of nirsevimab introduction against respiratory syncytial virus in the Valencian Community: a preliminary assessment","volume":"42","author":"Estrella-Porter","year":"2024","journal-title":"Vaccine."},{"issue":"9","key":"2026101309121888000_r2","doi-asserted-by":"crossref","first-page":"736","DOI":"10.1136\/archdischild-2024-327153","article-title":"Effectiveness of nirsevimab immunoprophylaxis against respiratory syncytial virus-related outcomes in hospital and primary care settings: a retrospective cohort study in infants in Catalonia (Spain)","volume":"109","author":"Coma","year":"2024","journal-title":"Arch Dis Child."},{"issue":"1","key":"2026101309121888000_r3","doi-asserted-by":"crossref","first-page":"e2024066393","DOI":"10.1542\/peds.2024-066393","article-title":"Nirsevimab effectiveness against severe respiratory syncytial virus infection in the primary care setting","volume":"155","author":"L\u00f3pez-Lacort","year":"2025","journal-title":"Pediatrics."},{"issue":"8","key":"2026101309121888000_r4","doi-asserted-by":"crossref","first-page":"817","DOI":"10.1016\/S1473-3099(24)00215-9","article-title":"Effectiveness and impact of universal prophylaxis with nirsevimab in infants against hospitalisation for respiratory syncytial virus in Galicia, Spain: initial results of a population-based longitudinal study","volume":"24","author":"Ares-G\u00f3mez","year":"2024","journal-title":"Lancet Infect 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J."},{"issue":"2","key":"2026101309121888000_r7","doi-asserted-by":"crossref","first-page":"175","DOI":"10.3390\/vaccines13020175","article-title":"Nirsevimab prophylaxis for reduction of respiratory syncytial virus complications in hospitalised infants: the multi-centre study during the 2023\u20132024 season in Andalusia, Spain (NIRSEGRAND)","volume":"13","author":"Moreno-P\u00e9rez","year":"2025","journal-title":"Vaccines (Basel)."},{"issue":"11","key":"2026101309121888000_r8","doi-asserted-by":"crossref","first-page":"1189","DOI":"10.1016\/S1473-3099(25)00233-6","article-title":"Effectiveness and impact of nirsevimab in Chile during the first season of a national immunisation strategy against RSV (NIRSE-CL): a retrospective observational study","volume":"25","author":"Torres","year":"2025","journal-title":"Lancet Infect Dis."},{"issue":"26","key":"2026101309121888000_r9","doi-asserted-by":"crossref","first-page":"2425","DOI":"10.1056\/NEJMoa2309189","article-title":"Nirsevimab for 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Andaluc\u00eda, campa\u00f1a 2023\u20132024. [RSV infection prevention program using nirsevimab. Andalusia, 2023\u20132024 season]","author":"Consejer\u00eda de Salud y Consumo, Junta de Andaluc\u00eda"},{"issue":"2","key":"2026101309121888000_r20","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1093\/ije\/dyaa213","article-title":"Use of directed acyclic graphs (DAGs) to identify confounders in applied health research: review and recommendations","volume":"50","author":"Tennant","year":"2021","journal-title":"Int J Epidemiol."},{"key":"2026101309121888000_r21","doi-asserted-by":"crossref","first-page":"e078226","DOI":"10.1136\/bmj-2023-078226","article-title":"How to use directed acyclic graphs: guide for clinical researchers","volume":"388","author":"Feeney","year":"2025","journal-title":"BMJ."},{"issue":"2","key":"2026101309121888000_r22","doi-asserted-by":"crossref","first-page":"513","DOI":"10.2307\/2060176","article-title":"Small town growth in the United States: an analysis by size class and by 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