Cohabitation COVID-19 Transmission Rates in a United States Suburban Community: a retrospective study of familial infections

D’Onofrio, Louis E.; Buono, Frank D.; Cooper, Mark A.R.

Objectives SARS-CoV-2 is a highly contagious virus that causes Coronavirus Disease 2019 (COVID-19) and can affect people of any age with potential for serious symptoms. Since the start of the COVID-19 pandemic, global infection rates have been on the rise with world leaders looking to slow and stop viral transmission. This study is looking at suburban cohabitation/familial infection in order to compare to similar studies from other countries. Study Design A retrospective review of medical records was collected using the Connecticut Electronic Disease Surveillance System (CEDSS). Methods A total of 406 cases who tested positive for SARS-COV-2 from February to June 2020 were reviewed from three towns located in Connecticut, USA. Cohabitation infection rates were identified using the home addresses of those with confirmed SARS-CoV-2 test results, with the first documented case being the index case, and additional home members being the secondary cases. Results Secondary transmission of SARS-CoV-2 developed in 126 of 406 household contacts (31%). Linear regression indicated positive relationship between cohabitation and age. Conclusions The cohabitation infection attack rate of SARS-CoV-2 is significantly higher than previously reported. Age of household contacts and spousal relationship to the index case are risk factors for transmission of SARS-CoV-2 within a household.