Study shows temporary isolation rooms provide effective protection against healthcare-associated transmission of COVID-19

Temporary isolation units used to house COVID-19 patients at a large Singapore hospital during the global pandemic have allowed COVID-19 cases to be safely treated for 18 months without healthcare-associated transmission of SARS-CoV-2. The results of the study, published today in American Journal of Infection Control (REJECT), suggests that these wards may be a safe option for treating patients during future pandemics caused by a new respiratory pathogen.

“This study provides important information that supports the safety of the temporary isolation units, which have become a critical option for many healthcare facilities around the world during the COVID-19 pandemic, and may be useful for practice during subsequent pandemics,” said Wee Liang En Yang, Deputy Consultant, Department of Infectious Diseases at Singapore Hospital (SGH), one from the lead authors of the article. “Despite the environmental contamination of SARS-CoV-2 observed in the temporary isolation rooms of our institution, we found no evidence of transmission medical workers for a long time.”

During the COVID-19 pandemic, the demand for isolation rooms for airborne infections to safely treat patients with the disease often exceeded their supply. Many health facilities set up temporary isolation rooms at the peak of the pandemic to provide additional capacity. However, there have been very few studies evaluating the effectiveness of these units in treating cases of COVID-19.

Over an 18-month period from July 2020 to December 2021, Dr. Wee and colleagues conducted environmental sampling for SARS-CoV-2 RNA in temporary isolation units built from prefab containers (N=20) or converted from shared wards with normal pressure (N=47) in SGH. Investigators completed sampling at the time of patient discharge/transfer and before terminal cleaning. During this period, the hospital also conducted contact tracing, active surveillance and whole genome sequencing (WGS) for all cases of COVID-19 among the hospital’s healthcare workers.

The researchers collected and evaluated a total of 355 swabs from the environment and determined that 22.4% (15/67) of patients had at least one positive sample. Compared with patients in converted isolation units, patients in isolation units built from prefab containers were more likely to be exposed to environmental contamination (adjusted odds ratio, aOR = 10.46, 95% CI = 3.89-58.91, p = 0.008), with the majority of positive environmental samples obtained from the toilet area (60.0%, 12/20) and a significant proportion from patient equipment, including electronic devices used to communicate with patients (8/20, 40.0%). Among patients in converted temporary isolation units, environmental contamination was also most frequently detected in the toilet area (17.0%, 8/47), while only 4.3% (2/47) of these patients had positive samples from the equipment of the patient (call- bell).

During the study period, SGH reported 441 cases of HCW infection, 5.7% (25/441) of which were among HCWs working in any of the hospital’s COVID-19 isolation units. While seven of these cases occurred among HCWs working in temporary isolation facilities, WGS and epidemiological investigations did not provide evidence of patient-to-HCW or HCW-to-HCW transmission.

“This study suggests that with the right combination of infection prevention practices, including well-designed isolation rooms, appropriate cleaning processes, adherence to prevention protocols, and appropriate use of personal protective equipment, temporary isolation rooms are a viable option to help safely manage patients during respiratory outbreaks. diseases,” said Linda Dickey, RN, MPH, CIC, FAPIC, APIC 2022 president.

Courtesy of the Association of Infection Control Professionals