# Risk of viral respiratory infection associated with shared washroom between adjoining rooms: a test-negative study

## TL;DR

Residents sharing a washroom with an infected neighbor are more likely to catch a viral respiratory infection.

## Contribution

This study identifies shared adjoining washrooms as a risk factor for viral respiratory infections.

## Key findings

- Shared rooms increase VRI risk with an odds ratio of 2.28.
- Shared adjoining washrooms increase VRI risk with an odds ratio of 1.65.
- Preventive measures for shared rooms should also apply to shared washrooms.

## Abstract

In test-negative study of residents exposed to viral respiratory infection (VRI), odds of VRI (excluding SARS-CoV-2) was higher with shared room (OR = 2.28, 95% CI, 1.53–3.40) and shared adjoining washroom (OR = 1.65, 95% CI, 1.03–2.64) than neighboring rooms. Measures recommended for exposed residents in shared rooms should be considered for shared washrooms.