Mortality trends during the first three waves of the COVID-19 pandemic at an urban district hospital in South Africa: A retrospective comparative analysis

Abstract

Background. Severe acute respiratory syndrome coronavirus 2 (SARS‐COV‐2) is the virus responsible for the COVID‐19 (C19) pandemic. South Africa (SA) experienced multiple periods of increased transmission. Tertiary, regional and central hospitals were overwhelmed, resulting in low acceptance rates. Objectives. To compare mortality trends of patients who died in hospital from SARS‐CoV‐2 infection during the first three waves of infection as defined by the National Institute of Communicable Diseases of South Africa. Methods. This was a retrospective cohort study at a district level hospital of 311 adults who died within the first three waves of COVID‐19. The study analysed case and crude fatality rates, baseline characteristics, symptomatology, clinical presentation and management of patients. Results. Waves 1, 2 and 3 yielded case fatality rates of 14.5%, 27.6% and 6.3%, respectively, and crude fatality rates of 16.7%, 33.0% and 12.2%, respectively. Black Africans were less likely to die during the third wave (odds ratio (OR) 0.54; 95% confidence interval (CI) 0.31 ‐ 0.94). Patients in the second wave had clinical frailty scores of <5 (OR 2.51; 95% CI 1.56 ‐ 4.03). Obesity was most prevalent in the second wave (OR 1.87; 95% CI 1.01 ‐ 3.46), and dyslipidaemia (OR 3.03; 95% CI 1.59 ‐ 5.77) and ischaemic heart disease (OR 3.77; 95% CI .71 ‐ 8.33) were most prevalent during the third wave. Severe ground glass appearance was most common during the second wave (OR 2.37; 95% CI 1.49 ‐ 3.77). Renal impairment was most prevalent during the first wave (OR 3.28; 95% CI 1.59 ‐ 6.77), and thrombo‐ embolic phenomena were less common during wave three (OR 0.12; 95% CI 0.02 ‐ 0.91). Conclusion. The Beta variant was the most virulent, with the highest case and crude fatality rates in wave 2.