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An In vitro Model to Study Immune Responses of Human Peripheral Blood Mononuclear Cells to Human Respiratory Syncytial Virus Infection
Published on: December 10, 2013
Risk Analysis of Respiratory Syncytial Virus Among Infants in the United States by Birth Month
Jason R Gantenberg1,2, Robertus van Aalst1,3,4, Monika Reddy Bhuma1
1Department of Health Services, Policy and Practice, Brown University School of Public Health, Providence, Rhode Island, USA.
Insights
Infants born in late spring/summer face higher risks for medically attended RSV lower respiratory tract infections. Nirsevimab can help protect infants, especially those born near the end of the RSV season.
Area of Science:
- Pediatrics
- Infectious Diseases
- Public Health
Background:
- Respiratory syncytial virus (RSV) significantly impacts infant morbidity and mortality in the US.
- Infant's birth month influences their age and timing of first RSV exposure.
- Understanding birth month-specific risks is crucial for targeted prevention strategies.
Purpose of the Study:
- To estimate the risk of medically attended (MA) RSV lower respiratory tract infection (LRTI) based on infant birth month.
- To analyze risks during the first RSV season and the first year of life (FYOL).
Main Methods:
- Analysis of three US insurance claims databases (commercial and Medicaid) for infants born July 2016-February 2020.
- Classification of MA RSV LRTI episodes by care level (outpatient, ED, inpatient) using diagnostic coding algorithms.
- Primary analysis focused on the first RSV season; secondary analysis compared first season to FYOL risks.
Main Results:
- Infants born May-September showed the highest risk for first-season MA RSV LRTI (6-26% depending on diagnostic definition).
- Infants born October-December had the highest risk for RSV-related hospitalization in their first season.
- Overall MA RSV LRTI risk across the FYOL was comparable across birth months (6-30%), with many cases managed outpatient or in EDs.
Conclusions:
- Findings support nirsevimab recommendations for US infants.
- Administering nirsevimab before the second RSV season may reduce outpatient and ED visits for infants not treated earlier.
Background:
Respiratory syncytial virus (RSV) is a major cause of morbidity and mortality among US infants. A child's calendar birth month determines their age at first exposure(s) to RSV. We estimated birth month-specific risk of medically attended (MA) RSV lower respiratory tract infection (LRTI) among infants during their first RSV season and first year of life (FYOL).
Methods:
We analyzed infants born in the USA between July 2016 and February 2020 using three insurance claims databases (two commercial, one Medicaid). We classified infants' first MA RSV LRTI episode by the highest level of care incurred (outpatient, emergency department, or inpatient), employing specific and sensitive diagnostic coding algorithms to define index RSV diagnoses. In our main analysis, we focused on infants' first RSV season. In our secondary analysis, we compared the risk of MA RSV LRTI during infants' first RSV season to that of their FYOL.
Results:
Infants born from May through September generally had the highest risk of first-season MA RSV LRTI-approximately 6-10% under the specific RSV index diagnosis definition and 16-26% under the sensitive. Infants born between October and December had the highest risk of RSV-related hospitalization during their first season. The proportion of MA RSV LRTI events classified as inpatient ranged from 9% to 54% (specific) and 5% to 33% (sensitive) across birth month and comorbidity group. Through the FYOL, the overall risk of MA RSV LRTI is comparable across birth months within each claims database (6-11% under the specific definition, 17-30% under the sensitive), with additional cases progressing to care at outpatient or ED settings.
Conclusions:
Our data support recent national recommendations for the use of nirsevimab in the USA. For infants born at the tail end of an RSV season who do not receive nirsevimab, a dose administered prior to the onset of their second RSV season could reduce the incidence of outpatient- and ED-related events.
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