Genomic epidemiology as a tool for understanding drivers of hepatitis A community outbreaks in Massachusetts and New Hampshire
- 1Massachusetts Department of Public Health
Abstract
Despite the existence of an effective vaccine, the United States continues to experience outbreaks of hepatitis A, including in Massachusetts (MA) and New Hampshire (NH) in 2018 and again in MA in 2023. To clarify the relationship between these outbreaks and better understand their drivers, we generated hepatitis A virus whole genome sequences from reported cases and analyzed them using open-source genotyping tools developed and released as part of this study. We found that the 2018 and 2023 outbreaks were caused by distinct viral strains, despite affecting individuals with similar demographic characteristics and reported risk factors. Detailed analysis of genomic and epidemiologic data further resolved transmission patterns within and across outbreaks, showing that experiencing homelessness and prior use of drugs were associated with increased transmission while also revealing transmission between individuals with and without these risk factors, as well as spread across state borders. Together, these findings demonstrate the value of broadly accessible genomic tools for understanding hepatitis A outbreaks and illustrate how whole genome analysis can complement epidemiological investigation by resolving transmission patterns and outbreak drivers that can inform public health interventions.
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BibTeX
@misc{krasilnikova2026genomic,
title = {{Genomic epidemiology as a tool for understanding drivers of hepatitis A community outbreaks in Massachusetts and New Hampshire}},
author = {L. A. Krasilnikova and L. Bouton and T. M. Brock-Fisher and E. Decker and M. Godec and Z. Thompson and E. Dart and F. Gao and A. Gladden-Young and K. S. Messer and J. Norville and I. Specht and A. Osinski and J. Li and C. Lones and K. C. DeRuff and K. J. Siddle and D. Church and C. Benton and K. Hansen and H. Bowen and S. Bhattacharyya and N. Epie and C. M. Brown and L. C. Madoff and B. L. MacInnis and G. R. Gallagher and S. Smole and C. Bean and E. A. Talbot and M. Burns and M. Doucette and E. Fortes and D. J. Park and P. C. Sabeti and S. Wohl},
howpublished = {medRxiv},
year = {2026},
month = may,
doi = {10.64898/2026.05.14.26352933},
url = {https://www.medrxiv.org/content/10.64898/2026.05.14.26352933v2},
note = {CC BY},
}
RIS
TY - UNPB
TI - Genomic epidemiology as a tool for understanding drivers of hepatitis A community outbreaks in Massachusetts and New Hampshire
AU - L. A. Krasilnikova
AU - L. Bouton
AU - T. M. Brock-Fisher
AU - E. Decker
AU - M. Godec
AU - Z. Thompson
AU - E. Dart
AU - F. Gao
AU - A. Gladden-Young
AU - K. S. Messer
AU - J. Norville
AU - I. Specht
AU - A. Osinski
AU - J. Li
AU - C. Lones
AU - K. C. DeRuff
AU - K. J. Siddle
AU - D. Church
AU - C. Benton
AU - K. Hansen
AU - H. Bowen
AU - S. Bhattacharyya
AU - N. Epie
AU - C. M. Brown
AU - L. C. Madoff
AU - B. L. MacInnis
AU - G. R. Gallagher
AU - S. Smole
AU - C. Bean
AU - E. A. Talbot
AU - M. Burns
AU - M. Doucette
AU - E. Fortes
AU - D. J. Park
AU - P. C. Sabeti
AU - S. Wohl
PY - 2026
DA - 2026/05/14
PB - medRxiv
DO - 10.64898/2026.05.14.26352933
UR - https://www.medrxiv.org/content/10.64898/2026.05.14.26352933v2
AB - Despite the existence of an effective vaccine, the United States continues to experience outbreaks of hepatitis A, including in Massachusetts (MA) and New Hampshire (NH) in 2018 and again in MA in 2023. To clarify the relationship between these outbreaks and better understand their drivers, we generated hepatitis A virus whole genome sequences from reported cases and analyzed them using open-source genotyping tools developed and released as part of this study. We found that the 2018 and 2023 outbreaks were caused by distinct viral strains, despite affecting individuals with similar demographic characteristics and reported risk factors. Detailed analysis of genomic and epidemiologic data further resolved transmission patterns within and across outbreaks, showing that experiencing homelessness and prior use of drugs were associated with increased transmission while also revealing transmission between individuals with and without these risk factors, as well as spread across state borders. Together, these findings demonstrate the value of broadly accessible genomic tools for understanding hepatitis A outbreaks and illustrate how whole genome analysis can complement epidemiological investigation by resolving transmission patterns and outbreak drivers that can inform public health interventions.
ER -