Environnmental detection of SARS-CoV-2 in hospital rooms in different wards of an University hospital

 Environmental detection of SARS-CoV-2 in hospital rooms in different wards of a University hospital

Barrigah-Benisan K, Ory J, Boudet A, Stephan R, Scotto A, Lavigne JP
https://doi.org/10.1016/j.jhin.2022.07.029

To assess the relationship between patient covid-19 status and environmental contamination

Patients’s diagnosis occur at J1 and surfaces samples at J7 before daily room disinfection. Each sampled room was occupied by a patient at least 24 h prior to disinfection.

Close surfaces samples were:

• Nurse call controller
• Bedside rail or bed lifting bar
• Telephone or TV remote
• Overbed table

All remote surfaces were:

• Bathroom doorknob
• Bathroom sink
• Toilet seat
• Doorknob
• Air vent
• Bathroom sink tap
• Toilet button

All rooms were daily decontaminated according to French recommendations.

13 samples rooms: 5 in the infectious diseases unit (IDU), 2 in the geriatric unit (GU), 2 in the Intensive care unit (ICU) et 2 in the long-term care unit (LTCU), 2 in the nursing home (NH)

156 samples have been done before the daily disinfection and 52 after the disinfection to assess the efficacy of the protocol.

5 rooms/13 show positive samples

O positive result in ICU nor NH

The most frequent contaminated locations are:

1- Samples close to the patient:

• Nurse call controller: 2
• Bed rail: 1
• Bed lifting bar: 1
• Telephone: 2
• Overbed table: 1

2- Remote samples:

• Bathroom doorknob: 1
• Bathroom sink tap: 1
• Toilet seat: 1

12/13 patients had symptoms of COVID but the highest numbers of positive samples were found in an asymptomatic patient room.

All samples after disinfection were negative.

Despite daily disinfection, 5 patients’ rooms showed contaminations at J7  usually close to the patients.

Surprisingly, the highest number of positive samples has been found in the asymptomatic patient’s room and 8 rooms with symptomatic patients have negative samples.  There was no relation between patients’ symptoms and environmental contamination.

The main contamination was close to the patient and probably due to coughing or sneezing.

All the patients in this study were bedridden and could not use the toilet. Nevertheless, remote contaminations were identified in several rooms. These results suggest contamination at distance by healthcare workers or aerosol emitted by the patients.  .

This study supports the evidence of the environmental shedding of SARS-CoV-2 until at least 7 days after symptoms appeared.

The absence of symptoms can also lead to environmental contamination.