University of Southern Denmark study links COVID-19 severity to shared environment

Researchers from the University of Southern Denmark have found that shared living environments, rather than genetics, play a more significant role in the severity of COVID-19 infections. The study analyzed data from 83,000 twins and over 32,000 of their life partners to distinguish between genetic influence and environmental factors.

While monozygotic twins share nearly identical genetic material, the study found no increased risk of hospitalization for twins of individuals hospitalized with COVID-19. In contrast, the risk was significantly higher among romantic partners. Partners of hospitalized individuals were more than three times as likely to require hospitalization compared to a control group. Specifically, if one partner was hospitalized, the other faced a 3.6-fold higher risk of hospitalization. In 71% of cases where both partners were hospitalized, the second person was admitted within five days of the first.