Cluster-Randomized Trial of Air Filtration and Ventilation to Reduce Covid19 Spread in Homes

Launched by STANFORD UNIVERSITY · Mar 18, 2023

Keywords

ClinConnect Summary

This study looks at whether improving air flow and using filtration fans in homes can reduce the spread of Covid-19 from a person who is already infected to other people living in the same home. In this two-group trial, households are randomly assigned to either the intervention (filtration fans plus ventilation guidance) or to usual care (no active filtration intervention). The main thing researchers will watch is how many susceptible household members develop Covid-19 by day 7. They’ll also look at whether new upper respiratory symptoms appear by day 7 and the average carbon dioxide (CO2) levels in the home over the first week, which helps gauge how well the air is ventilated.

Who can participate? Eligible households have at least 4 people (the person with Covid-19 plus at least 3 others) who share the home, and the index case must have been recently infected (within about 2 days). Participants can be children, adults, or older adults. Exclusion criteria include situations where too many household members are already considered infected, not enough contacts are willing to participate, or not enough people are expected to be in the home for most of the next 7 days. If enrolled, the intervention group gets one filtration fan per room (and one for the index case; two if you live in a studio), plus simple guidance on ventilation, a CO2 monitor, a mid-week check-in, and testing of household members at day 0-1 and day 7. The control group receives no filtration devices but will still receive a CO2 monitor and standard isolation guidance, with the same testing schedule. The trial is currently enrolling and is expected to complete around the end of 2025, with results not yet available.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Household members live in a shared space (apartment, home) with others (as opposed to renting single rooms in a shared space, for example)
• • At least 3 other people live in the household aside from index case
• Exclusion Criteria:
• • If index case test positive day was over 2 days prior
• • If half or more household members are thought to be infected already
• • If household has fewer than 3 contacts interested in participating in the study
• • If fewer than 3 contacts are expected to be present in the house for a majority of the following 7 days