• First analysis leveraging longitudinal personal exposure and serological data collected within a randomized clean-cooking trial to examine associations between household air pollution and COVID-19 infection. • Clean cooking intervention significantly reduced PM 2.5 and CO exposure but showed no effect on COVID-19 risk. • Exposure–response analyses suggested inverse associations between higher PM 2 . 5 exposure and SARS-CoV-2 antibody levels. • Household air pollution may impact COVID-19 infection risk differently than ambient air pollution. While extensive research has linked ambient air pollution to increased COVID-19 infection rates and severity, the role of household air pollution (HAP)—a major public health exposure affecting nearly 3 billion people globally—remains understudied. Here, we evaluate associations between a clean cooking intervention, personal household air pollution exposure, and serologic evidence of prior SARS-CoV-2 infection using exploratory intention-to-treat and exposure–response analyses. The Household Air Pollution Intervention Network (HAPIN) Trial randomized 3,200 households in Guatemala, India, Peru, and Rwanda to either continue using traditional solid fuel cookstoves or receive liquefied petroleum gas stoves with continuous fuel supply and behavioral messaging. The current ancillary study leveraged personal exposures to PM 2.5 and carbon monoxide (CO) and dried blood spot (DBS) samples collected in the Guatemala, India, and Peru HAPIN sites to study the association between personal air pollution exposures and COVID-19; Rwanda was excluded due to low COVID-19 prevalence at the time of collection. SARS-CoV-2-specific antibodies were measured from DBS samples to define serology-based infection status and quantify immune response. Analyses included exploratory intention-to-treat and observational exposure–response analyses of associations between personal air pollution exposure and serology-based SARS-CoV-2 infection status and antibody levels. While the intervention effectively reduced HAP exposures, no significant differences in COVID-19 infection or antibody levels between intervention and control groups were found. However, exposure–response analyses found higher PM 2.5 exposure was associated with lower odds of COVID-19 infection and lower antibody levels, diverging from most studies of ambient air pollution. These findings suggest that household air pollution may influence SARS-CoV-2 infection and immune response through mechanisms distinct from those described for ambient air pollution.
Underhill et al. (Sun,) studied this question.