A new study conducted at a federal nursing home for Canadian veterans has revealed that shared bathrooms between adjoining rooms — commonly known as “Jack and Jill” bathrooms — may significantly increase the risk of viral respiratory infections (VRIs) among residents.
The research, “Risk of Viral Respiratory Infection Associated With Shared Washroom Between Adjoining Rooms: A Test-Negative Study,” was recently published in the journal, Infection Control & Hospital Epidemiology. Researchers studied more than 4,300 resident exposures over 13 years and found that individuals sharing a bathroom with an infected neighbor had a 65% higher chance of contracting a non-COVID viral infection compared to those in neighboring rooms without shared facilities. The risk was even greater for residents in shared bedrooms, who had more than double the odds of infection.
Although the link between shared rooms and infection risk is well-established, this study was among the first to systematically evaluate the impact of shared bathrooms. The authors noted that the findings should be considered as an infection control strategy, especially in older facilities where such layouts are common.
“From a design standpoint, private rooms with a dedicated washroom are the safest accommodation for long-term care residents,” co-author Jerome A. Leis, MD, MSc, told Healio. Dr. Leis is medical director of infection prevention and control at the Sunnybrook Health Sciences Centre and associate professor at the University of Toronto. “At the same time, improving infrastructure will take many years and in the meantime increased awareness about shared washrooms can help inform risk assessment by infection prevention teams.”
The study used a test-negative design and included a wide range of respiratory viruses such as influenza, RSV and rhinovirus. Interestingly, the increased risk associated with shared washrooms was not observed for SARS-CoV-2, possibly due to broader transmission patterns and smaller sample sizes.
Researchers recommend that nursing homes with shared bathroom configurations consider enhanced precautions, including:
- Use of dedicated toilets
- Keeping bathroom doors closed
- Increasing surveillance for symptoms
- Using preventive antiviral treatments during outbreaks
The study supports Canadian health care design standards that favor single-resident rooms with private bathrooms. By contrast, U.S. guidelines do not specifically address shared bathrooms, though they limit room and toilet sharing.
Despite its limitations, including being conducted at a single site, the study underscores the need for further research and potential policy updates to protect vulnerable populations in long-term care settings.
