%0 Journal Article
%@ 2369-2960
%I JMIR Publications
%V 8
%N 11
%P e38898
%T The Risk of Hospitalization and Mortality After Breakthrough SARS-CoV-2 Infection by Vaccine Type: Observational Study of Medical Claims Data
%A Kshirsagar,Meghana
%A Nasir,Md
%A Mukherjee,Sumit
%A Becker,Nicholas
%A Dodhia,Rahul
%A Weeks,William B
%A Ferres,Juan Lavista
%A Richardson,Barbra
%+ Microsoft, 1 Microsoft Way, Redmond, WA, 98052, United States, 1 425 638 7777, meghana.ksagar@gmail.com
%K breakthroughs
%K vaccines
%K Pfizer
%K Moderna
%K Janssen
%K SARS-CoV-2
%K COVID-19
%K coronavirus
%K infectious disease
%K viral infection
%K vaccination
%K breakthrough infection
%K public health
%K health policy
%K decision making
%K booster vaccine
%K mortality
%K hospitalization
%K healthcare system
%D 2022
%7 8.11.2022
%9 Original Paper
%J JMIR Public Health Surveill
%G English
%X Background: Several risk factors have been identified for severe COVID-19 disease by the scientific community. In this paper, we focus on understanding the risks for severe COVID-19 infections after vaccination (ie, in breakthrough SARS-CoV-2 infections). Studying these risks by vaccine type, age, sex, comorbidities, and any prior SARS-CoV-2 infection is important to policy makers planning further vaccination efforts. Objective: We performed a comparative study of the risks of hospitalization (n=1140) and mortality (n=159) in a SARS-CoV-2 positive cohort of 19,815 patients who were all fully vaccinated with the Pfizer, Moderna, or Janssen vaccines. Methods: We performed Cox regression analysis to calculate the risk factors for developing a severe breakthrough SARS-CoV-2 infection in the study cohort by controlling for vaccine type, age, sex, comorbidities, and a prior SARS-CoV-2 infection. Results: We found lower hazard ratios for those receiving the Moderna vaccine (P<.001) and Pfizer vaccine (P<.001), with the lowest hazard rates being for Moderna, as compared to those who received the Janssen vaccine, independent of age, sex, comorbidities, vaccine type, and prior SARS-CoV-2 infection. Further, individuals who had a SARS-CoV-2 infection prior to vaccination had some increased protection over and above the protection already provided by the vaccines, from hospitalization (P=.001) and death (P=.04), independent of age, sex, comorbidities, and vaccine type. We found that the top statistically significant risk factors for severe breakthrough SARS-CoV-2 infections were age of >50, male gender, moderate and severe renal failure, severe liver disease, leukemia, chronic lung disease, coagulopathy, and alcohol abuse. Conclusions: Among individuals who were fully vaccinated, the risk of severe breakthrough SARS-CoV-2 infection was lower for recipients of the Moderna or Pfizer vaccines and higher for recipients of the Janssen vaccine. These results from our analysis at a population level will be helpful to public health policy makers. Our result on the influence of a previous SARS-CoV-2 infection necessitates further research into the impact of multiple exposures on the risk of developing severe COVID-19. 
%M 36265
%R 10.2196/38898
%U https://publichealth.jmir.org/2022/11/e38898
%U https://doi.org/10.2196/38898
%U http://www.ncbi.nlm.nih.gov/pubmed/36265