COVID-19: A comparative study of severity of patients hospitalized during the first and the second wave in South Africa.

BackgroundSouth Africa has experienced two waves of COVID-19 infections, the second of which was inter alia attributed to the emergence of a novel SARS-CoV2 variant, 501Y.V2. This variant possibly has increased virulence and may be associated with increased mortality. The objective of this study was to determine if patients admitted in the second wave had more severe illness and higher mortality than those admitted in the first. MethodsWe analysed and compared the characteristics, biological severity markers, treatments, level of care and outcomes of patients hospitalised in a private hospital in the Eastern Cape Province, South Africa. ResultsCompared to the first wave, patients admitted in the second were older and less likely to have co-morbidities. In contrast, the D-dimer and interleukin-6 (IL-6) levels were significantly higher. Despite this, significantly less patients were admitted to ICU and/or were mechanically ventilated. The total length of hospital stay was identical in both groups. Whereas the overall mortality was not significantly higher during the second wave, the ICU mortality was. Those that died in the second wave were older than those in the first wave. Multivariable logistic regression showed that being admitted during the second wave was an independent risk factor for mortality. ConclusionThis study appears to confirm previous reports that the 501Y.V2 variant is possibly more virulent as indicated by the higher levels of D-dimer and IL-6, the slight increase in mortality of hospitalised patients and the higher ICU mortality in the second wave.