Asymptomatic testing people for SARS-CoV-2 in healthcare facilities: A systematic review

Background: Asymptomatic testing involves the process whereby individuals who do not show symptoms of COVID-19 are tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using any of the available laboratory test techniques. Aim: To evaluate the effectiveness of testing asymptomatic individuals visiting, living or working in healthcare facilities in reducing SARS-CoV-2 viral infections. Setting: Healthcare databases. Method: Electronic databases were searched and limited to English language and studies published 2020 to 02 September 2022. Following the methods for rapid systematic reviews, data were analysed using a fixed effect model, and results of the effect estimate were reported as odds ratios (OR) with their confidence intervals (CI) (95% CI). Results: Databases' searches yielded 3065 articles after deduplication and 3 studies by searching reference lists of included articles. After screening abstracts and full text articles, 3 cohort studies were included, each with serious risk of bias. Very low certainty evidence shows a decrease in occurrence of SARS-CoV-2 infections in the asymptomatic testing group among patients going for index surgery (OR: 0.05, 95 % CI: 0.00-0.82; 501 participants; 1 study) and among long term care facility staff (OR: 0.31, 95 % CI: 0.18-0.52; 3457 participants; 2 studies, I2 = 89%) than the 'no asymptomatic testing' group. However, its effect on their residents was contradictory. Conclusion: There is limited quality evidence to support asymptomatic testing of individuals for SARS-CoV-2 in the prevention of virus transmission in health care settings. Contribution: In the event of a future pandemic, this review offers current evidence on the potential effects of asymptomatic testing.