{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T22:34:14Z","timestamp":1792794854887,"version":"4.5.0"},"reference-count":37,"publisher":"American Medical Association (AMA)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Pediatr"],"published-print":{"date-parts":[[2026,2,1]]},"abstract":"<jats:sec id=\"ab-poi250073-4\">\n                    <jats:title>Importance<\/jats:title>\n                    <jats:p>Nirsevimab, a long-acting monoclonal antibody available since 2023, has demonstrated effectiveness in preventing lower respiratory tract infection (LRTI) caused by respiratory syncytial virus (RSV) in clinical trials and postlicensure settings. However, its broader real-world associations with respiratory-related outcomes in infants remain unclear, and characterizing these associations is essential to inform pediatric immunization policy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-5\">\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To evaluate the real-world association of nirsevimab with LRTI-related hospitalizations and emergency department (ED) visits in infants.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-6\">\n                    <jats:title>Data Sources<\/jats:title>\n                    <jats:p>MEDLINE, Embase, Web of Science, Scopus, Global Health, and medRxiv databases were systematically searched for observational studies published between January 1, 2023, and June 20, 2025. Data analysis was performed between January 1, 2025, and June 20, 2025.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-7\">\n                    <jats:title>Study Selection<\/jats:title>\n                    <jats:p>Postlicensure observational studies reporting original data on the effectiveness of nirsevimab immunization programs in infants and children aged 24 months or younger in routine clinical settings were eligible for inclusion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-8\">\n                    <jats:title>Data Extraction and Synthesis<\/jats:title>\n                    <jats:p>Two reviewers independently extracted data and assessed study quality using the Critical Appraisal Checklist of the Joanna Briggs Institute. Random-effects meta-analysis was conducted to estimate pooled odds ratios (ORs) and 95% confidence intervals.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-9\">\n                    <jats:title>Main Outcomes and Measures<\/jats:title>\n                    <jats:p>Primary outcomes were all-cause LRTI-related hospitalization, all-cause hospitalization, all-cause LRTI-related ED visit, and RSV-LRTI\u2013related ED visit.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-10\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Of 1752 records screened, 15 studies met inclusion criteria; 11 studies were from 5 countries included in the meta-analysis, comprising 236\u202f764 infants and children in the nirsevimab group and 27\u202f522 in the control group. Compared with controls, nirsevimab was associated with lower odds of all-cause LRTI-related hospitalization (OR, 0.38; 95% CI, 0.28-0.53), all-cause LRTI-related ED visits (OR, 0.52; 95% CI, 0.37-0.73), and RSV-LRTI\u2013related ED visits (OR, 0.24; 95% CI, 0.13-0.47). No significant difference was observed in all-cause hospitalizations (OR, 0.56; 95% CI, 0.14-2.20) between the nirsevimab and control groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-poi250073-11\">\n                    <jats:title>Conclusions and Relevance<\/jats:title>\n                    <jats:p>In this meta-analysis, nirsevimab was associated with reduced LRTI-related hospitalizations and ED visits in infants and young children. These findings support nirsevimab\u2019s potential to reduce respiratory-related morbidity in young children and health care utilization.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1001\/jamapediatrics.2025.5280","type":"journal-article","created":{"date-parts":[[2025,12,22]],"date-time":"2025-12-22T16:31:09Z","timestamp":1766421069000},"page":"152","source":"Crossref","is-referenced-by-count":13,"title":["Nirsevimab Against Hospitalizations and Emergency Department Visits for Lower Respiratory Tract Infection in Infants"],"prefix":"10.1001","volume":"180","author":[{"given":"Dewan Md.","family":"Sumsuzzman","sequence":"first","affiliation":[{"name":"Agent-Based Modelling Laboratory, York University, Toronto, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Congjie","family":"Shi","sequence":"additional","affiliation":[{"name":"Agent-Based Modelling Laboratory, York University, Toronto, Ontario, 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