Data from 513 households and 2,053 people participating in the Coronavirus Household Evaluation and Respiratory Testing (C-HEaRT) study from August 2020 to August 2021 in Utah and from September 2020 to August 2021 in New York City, plus data from the SARS-CoV-2 Epidemiology And Response in Children (SEARCh) study in Maryland, with data collected from November 2020 to October 2021, reveal that isolating from infected family members (separate room) and getting a vaccine helped prevent  severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections.

Participants collected and submitted nasal swabs weekly and with the onset of acute illness. The study, which followed participants through the Alpha and Delta waves, captured both asymptomatic and symptomatic infections with SARS-CoV-2. Participants completed weekly surveys about symptoms experienced in the preceding week and, if they had symptoms, what preventive measures they took such as isolating or wearing a mask.

The study did not find that COVID-19 vaccination reduced transmission within households but did reduce overall infection risk. COVID-19 transmission in households with children found that the virus that causes COVID-19 was transmitted from people of all ages and from those with or without symptoms. However, staying in a separate room from other household members while sick significantly reduced the odds of transmission of the virus

Data collection was conducted before the emergence of the Omicron variant and vaccines for children in the United States.