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An Improved and High Throughput Respiratory Syncytial Virus RSV Micro-neutralization Assay
Published on: January 26, 2019
Nirsevimab Effectiveness Against Medically Attended Respiratory Syncytial Virus Illness and Hospitalization Among
Insights
Nirsevimab effectively prevents medically attended respiratory syncytial virus (RSV) illness and hospitalization in American Indian and Alaska Native infants and at-risk children. This monoclonal antibody offers significant protection for those in their first or second RSV season.
Area of Science:
- Pediatric Infectious Diseases
- Immunology
- Public Health
Background:
- Respiratory syncytial virus (RSV) is a major cause of pediatric hospitalizations.
- American Indian and Alaska Native (AI/AN) children face disproportionately high rates of RSV hospitalization.
- Nirsevimab, a monoclonal antibody, was recommended in August 2023 for infants and at-risk children to prevent severe RSV.
Purpose of the Study:
- To evaluate the effectiveness of nirsevimab in AI/AN children in Alaska.
- To assess nirsevimab's impact on medically attended RSV illness and hospitalization during the 2023-2024 season.
Main Methods:
- A retrospective evaluation was conducted in Alaska's Yukon-Kuskokwim Delta region.
- Effectiveness was estimated among 472 AI/AN children with medically attended acute respiratory illness (ARI).
- Participants were analyzed based on whether they received nirsevimab (≥7 days prior) and their RSV season (first or second).
Main Results:
- Overall, 48% of children with ARI had received nirsevimab.
- For children in their first RSV season (n=292), nirsevimab effectiveness was 76% against medically attended RSV illness and 89% against RSV hospitalization.
- For children in their second RSV season (n=180), effectiveness was 88% against medically attended RSV illness.
Conclusions:
- Nirsevimab demonstrates significant effectiveness in preventing medically attended RSV illness and hospitalization in AI/AN infants and at-risk children.
- The findings support nirsevimab's role in protecting vulnerable populations, including AI/AN children, against severe RSV outcomes.
- Nirsevimab is a valuable tool for preventing severe RSV in infants and children at increased risk, including those in their first or second RSV season.
Abstract:
Respiratory syncytial virus (RSV) is a leading cause of hospitalization among young children. Historically, American Indian and Alaska Native (AI/AN) children have experienced high rates of RSV-associated hospitalization. In August 2023, a preventive monoclonal antibody (nirsevimab) was recommended for all infants aged <8 months (born during or entering their first RSV season) and for children aged 8-19 months (entering their second RSV season) who have increased risk for severe RSV illness, including all AI/AN children. This evaluation in Alaska's Yukon-Kuskokwim Delta region estimated nirsevimab effectiveness among AI/AN children in their first or second RSV seasons during 2023-2024. Among 472 children with medically attended acute respiratory illness (ARI), 48% overall had received nirsevimab ≥7 days earlier (median = 91 days before the ARI-related visit). For children in their first RSV season (292), nirsevimab effectiveness was 76% (95% CI = 42%-90%) against medically attended RSV illness and 89% (95% CI = 32%-98%) against RSV hospitalization. For children in their second RSV season (180), effectiveness against medically attended RSV illness was 88% (95% CI = 48%-97%). Nirsevimab is effective for preventing severe RSV illness among infants entering their first RSV season and children entering their second season with increased risk for severe RSV, including all AI/AN children.
