COVID-19 and health care worker exposure at Chris Hani Baragwanath Academic Hospital

Background: Health care workers (HCWs) are at increased risk of coronavirus disease 2019 (COVID-19). Appropriate risk assessments and testing are essential to reduce transmission and avoid workforce depletion. Objective: To investigate the risk of COVID-19 infection among HCWs who fulfil the person under investigation case definition or had exposure to a confirmed COVID-19 contact. Methods: We conducted a retrospective review of HCWs who were exposed to and/or tested for COVID-19 during the first wave of the pandemic. Data collected included demographics, exposure type, risk level, and COVID-19 test result. Frequency distribution tables, bivariate analyses, univariate and multivariate analyses were conducted. Results: Among the 1111 HCWs reviewed, 643 were tested with 35.6% positive results. PUI's accounted for 62.4% of positive cases. Symptomatic HCWs with no known contact were at a greater risk of infection than those with a patient exposure (p═0.001). The risk of testing positive was higher after a patient exposure (p═0.000) compared to a co-worker contact. Patient-facing designations had a higher risk of SARS-CoV-2 infection than non-clinical designations (p═0.013). The exception to this was security personnel who were 28 times more likely to test positive than any other designation (p═0.000). Conclusion: There is a higher positivity rate among HCWs than the general population. The presence of symptoms warrants testing. Nosocomial transmission was derived from patients more than co-worker contacts. Precautions in the workplace need to be reinforced to protect the health and safety of HCWs during this pandemic. These findings should assist with preparedness for future pandemics.