OBJECTIVES: We primarily quantified exposure patterns, transmission characteristics, and the clinical spectrum of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among household contacts of individuals with severe coronavirus disease (COVID-19).

METHODS: We conducted a retrospective cohort study of 20 index patients hospitalized with severe COVID-19 and 79 of their household contacts . We determined the transmission frequency, range of manifestations of SARS-CoV-2 infection, and factors associated with infection in household settings .

RESULTS: Of the 79 household contacts , 53 (67 %) developed SARS-CoV-2 infection [49 (62 %) symptomatic , 4 (5 %) asymptomatic]. Eight patients (10 %) developed severe COVID-19, and one died of COVID-19 pneumonia (case-fatality rate : 1.9 %). The probability of SARS-CoV-2 infection was similar in children and adults (55% vs. 72%, P=0.14), with children being less likely to develop symptomatic disease (46% vs. 68%, P=0.06). Handwashing & #8805; 5 times/day was associated with reduced infection risk (52.8% vs. 76.9%, P=0.04).

CONCLUSIONS: SARS-CoV-2 has a high frequency of transmission among household contacts . Non-hospitalized individuals with SARS-CoV-2 infection should be quarantined in patient care facilities rather than at home to minimize spread, if possible, and frequent handwashing should be practiced to prevent transmission . This article is protected by copyright . All rights reserved.