Household transmissions of SARS-CoV-2 in the time of unprecedented travel lockdown in China.

ABSTRACT

QUESTION What are the characteristics of household and social transmissions of COVID-19 areas outside of epidemic centers? FINDINGS: Based on 1,407 COVID-19 reported infection events in China outside of Hubei Province between 20 January and 19 February 2020, we estimate the distribution of secondary infection sizes, frequency of super spreading events, serial intervals and age-stratified hazard of infection. Young and older people have higher risks of being infected with households while males 65+ of age are responsible for a disproportionate number of household infections. Meaning This report is the first large-scale analysis of the household and social transmission events in the COVID-19 pandemic.