tetano
Editor, Senior Moderator
Influenza Other Respir Viruses
. 2025 Apr;19(4):e70094.
doi: 10.1111/irv.70094. Respiratory Syncytial Virus Incidence in Young Children in the United States: Impact of Methodologies and Patient Characteristics
Sabina O Nduaguba[SUP] 1 2 3 [/SUP], Phuong T Tran[SUP] 1 4 [/SUP], Renata Shih[SUP] 5 [/SUP], Lyn Finelli[SUP] 6 [/SUP], Yoonyoung Choi[SUP] 6 [/SUP], Yanning Wang[SUP] 7 8 [/SUP], Almut G Winterstein[SUP] 1 7 9 [/SUP]
Affiliations
Objectives: This study aimed to estimate the incidence of respiratory syncytial virus (RSV) infections in US inpatient and outpatient settings.
Methods: We established national cohorts of privately insured children < 5 years (2011-2019) to estimate annual and seasonal incidences of lower respiratory tract infection (LRTI), RSV-LRTI, and RSV acute respiratory infection (RSV-ARI), stratified by age and high-risk conditions per American Academy of Pediatrics definitions. Sensitivity analyses varied episode definitions and assessed the impact of immunoprophylaxis and RSV under-ascertainment.
Results: Among 6,767,107 children, annual RSV-LRTI rates dropped with increasing age in both inpatient (7.9 for age < 1 year to 0.2 for age 4 per 1000 person-years) and outpatient settings (48.3 to 1.6). Most RSV-ARI (~80%-90%) was RSV-LRTI. RSV-LRTI accounted for > half of LRTI hospitalizations among infants (7.9 RSV-LRTI versus 14.7 LRTI) and for ~20% outpatient LRTI (48.3 versus 250.3), but this contribution declined with older age. Outpatient RSV-LRTI was > 5 times inpatient rates. Inpatient RSV-LRTI rates dropped consistently with increasing gestational age (GA) (35.6 for GA < 29 weeks versus 7.6 for term infants), while outpatient rates were similar across GA groups (54.0 versus 51.6). Infants with Down syndrome had the highest RSV-LRTI rates, and any high-risk group had rates >2 times higher than healthy term infants. Across all strata, seasonal rates were > 2 annual rates. Modeling suggested that claims data captured 42% of all RSV episodes.
Conclusion: This study provides national, population-based estimates of medically attended RSV infections across age groups and high-risk strata. Results allow granular assessments of disease burden to guide recommendations for new RSV prevention strategies.
Keywords: epidemiologic methods; incidence; respiratory syncytial virus infection.
. 2025 Apr;19(4):e70094.
doi: 10.1111/irv.70094. Respiratory Syncytial Virus Incidence in Young Children in the United States: Impact of Methodologies and Patient Characteristics
Sabina O Nduaguba[SUP] 1 2 3 [/SUP], Phuong T Tran[SUP] 1 4 [/SUP], Renata Shih[SUP] 5 [/SUP], Lyn Finelli[SUP] 6 [/SUP], Yoonyoung Choi[SUP] 6 [/SUP], Yanning Wang[SUP] 7 8 [/SUP], Almut G Winterstein[SUP] 1 7 9 [/SUP]
Affiliations
- PMID: 40176778
- DOI: 10.1111/irv.70094
Objectives: This study aimed to estimate the incidence of respiratory syncytial virus (RSV) infections in US inpatient and outpatient settings.
Methods: We established national cohorts of privately insured children < 5 years (2011-2019) to estimate annual and seasonal incidences of lower respiratory tract infection (LRTI), RSV-LRTI, and RSV acute respiratory infection (RSV-ARI), stratified by age and high-risk conditions per American Academy of Pediatrics definitions. Sensitivity analyses varied episode definitions and assessed the impact of immunoprophylaxis and RSV under-ascertainment.
Results: Among 6,767,107 children, annual RSV-LRTI rates dropped with increasing age in both inpatient (7.9 for age < 1 year to 0.2 for age 4 per 1000 person-years) and outpatient settings (48.3 to 1.6). Most RSV-ARI (~80%-90%) was RSV-LRTI. RSV-LRTI accounted for > half of LRTI hospitalizations among infants (7.9 RSV-LRTI versus 14.7 LRTI) and for ~20% outpatient LRTI (48.3 versus 250.3), but this contribution declined with older age. Outpatient RSV-LRTI was > 5 times inpatient rates. Inpatient RSV-LRTI rates dropped consistently with increasing gestational age (GA) (35.6 for GA < 29 weeks versus 7.6 for term infants), while outpatient rates were similar across GA groups (54.0 versus 51.6). Infants with Down syndrome had the highest RSV-LRTI rates, and any high-risk group had rates >2 times higher than healthy term infants. Across all strata, seasonal rates were > 2 annual rates. Modeling suggested that claims data captured 42% of all RSV episodes.
Conclusion: This study provides national, population-based estimates of medically attended RSV infections across age groups and high-risk strata. Results allow granular assessments of disease burden to guide recommendations for new RSV prevention strategies.
Keywords: epidemiologic methods; incidence; respiratory syncytial virus infection.