HALF of air samples taken from hallways and a fifth from bathrooms have high levels of coronavirus

High amounts of the novel coronavirus can be found in the air in several hospital settings, a new study suggests.

Researchers found that one-quarter of all ICU rooms with COVID-19 patients were contaminated with genetic material of the virus, known as SARS-CoV-2.

What’s more, more than 20 percent of samples from toilets and bathrooms as well as more than half of samples from hallways came back positive. 

The team, from Central Hospital at the University of Nantes, in France, says the high concentration of the virus, along with many people cramped in poorly ventilated rooms, could explain how frontline healthcare workers end up contracting the virus despite wearing personal protective equipment. 

Researchers looked at 24 studies from eight countries between January 1 and October 27 that examined COVID-19 and air contamination. Pictured: Medical staff members treat a patient in the COVID-19 ICU at the United Memorial Medical Center in Houston, Texas, December 22

A total of 23.8% of air samples taken from hospital toilets and bathrooms came back positive for viral genetic material as did 56.3% of samples taken from hallways

For the analysis, published in JAMA Network Open, the team searched for articles covering COVID-19 and air contamination between January 1 and October 27.

A total of 24 studies were included from eight countries including the U.S., the U.K., Italy, China, Hong Kong, Singapore, South Korea and Iran.

Air samples were taken from hospitalized patients’ rooms both in and out of ICUs; clinical areas including nurses’ stations; staff areas such as changing room; public areas such as hallways and main entrances; and toilets and/or bathrooms. 

Of the 893 samples taken, 17.4 percent were positive for viral RNA, or genetic material, of the coronavirus.

Air samples from ICU rooms were more than twice as likely to be positive for the virus at 25.2 percent compared to 10.7 percent for non-ICU rooms.    

Aside from ICU rooms, the highest percentage of contaminated samples came from restrooms and hallways. 

More than one-fifth, 23.8 percent, of samples taken from toilets and/or bathrooms were positive for SARS-CoV-2.  

Researchers say this is likely because bathrooms are small and poorly ventilated in addition to genetic material of the virus being found in stool samples. 

‘Toilet flushing may lead to the aerosolization of RNA in small and non-ventilated toilets or bathrooms,’ they wrote. 

Additionally, 56.3 percent of samples from hallways came back positive with an overall positivity rate of 33.3 percent in public areas.

Samples from staff areas were about 12 percent positive.

A total of 19.2 percent of positive samples were found in meeting rooms and 3.9 percent in changing rooms.   

‘The finding of high concentrations in staff rooms (ie, meeting and dining rooms) is consistent with the possible cross-transmission of COVID-19 among [healthcare professionals] during breaks,’ the authors wrote.

‘During these periods, face masks are frequently removed in small areas without ventilation.’

The team says that it’s not clear whether the air contains viruses viable enough to infect people and hopes to study this subject in future research.

‘High viral loads found in toilets and/or bathrooms, staff areas, and public hallways argue for a careful consideration of these areas for the prevention of COVID-19 transmission,’ the authors wrote.

‘However, the presence of viable viruses should be primarily considered, given that it is a required link for the potential of cross-transmission.’