Table 3.
Cumulative reported COVID-19 cases, hospitalizations, recorded deaths, and excess mortality in Gauteng Province by COVID-19 wave.
| Outcomes | Pre-BA.1-Dominant Wave Cumulative | BA.1-Dominant Wave | Omicron Sublineage Era | Total |
|---|---|---|---|---|
| Period of case wave | 7 March 2020 to 22 October 2021 | 23 October 2021 to 21 March 2022 | 22 March 2022 to 17 November 2022 | |
| Inferred infections from serosurvey 1 | 8,391,304 (8,265,033–8,506,096) | 10,167,996 (9,803,769–10,517,047) | Not applicable | |
| Cases—no. † | 926,193 | 279,829 | 135,272 | 1,341,294 |
| Cumulative case rate per 100,000 population | 5957 | 1805 | 523 | 8653 |
| Annualised case rate per 100,000 population | 3567 | 1080 | 313 | 5182 |
| Proportion of total cumulative cases, % | 69.1 | 20.9 | 10 | 100 |
| Inferred infection: recorded case ratio (95% CI) | 9.1 (8.9–9.2). | 36.3 (35.0–37.6) | Not applicable | |
| Period of COVID-19 hospitalisation wave | 7 March 2020 to November 1, 2021 | 2 November 2021 to 23 March 2022 | 24 March 2022, 2022 17 November 2022 | |
| Hospitalizations– no.‡ | 127,415 | 22,233 | 11,624 | 161,272 |
| Cumulative hospitalisation rate per 100,000 population | 822 | 143 | 75 | 1041 |
| Proportion of total cumulative hospitalisations, % | 79 | 13.8 | 7.2 | 100 |
| Inferred infection: recorded hospitalisation ratio (95% CI) | 65.9 (64.9–66.8) | 457.3 (441.0–473.0) | Not applicable | |
| Period of recorded COVID-19 deaths, wave | 31 March 2020 to 3 November 2021 | 4 November 2021 to 14 April 2022 | 15 April 2022 to 17 November 2022 | |
| Recorded deaths in wave—no. | 27,996 | 1802 | 913 | 30,711 |
| cumulative recorded death rate per 100,000 population § | 180.6 | 11.6 | 5.9 | 191.7 |
| Proportion of total cumulative recorded deaths, % | 91.2 | 5.8 | 3 | 100 |
| Inferred infection: recorded death ratio (95% CI) | 299.7 (295.2–303.8) | 5642.6 (5440.5–5836.3) | Not applicable | |
| Infection fatality risk (IFR) for recorded deaths (%) | 0.33. | 0.02 | Not applicable | |
| Period of excess deaths wave | 3 March 2020 to 27 November 2021 | 28 November 2021 to 19 March 2022 | 20 March 2022 to 17 November 2022 | |
| Excess deaths in wave–no. | 56,202 | 2974 | 6753 | 65,929 |
| Cumulative excess death rate per 100,000 population | 362.6 | 19.2 | 43.6 | 425 |
| Proportion of total cumulative excess deaths, % | 85.3 | 4.5 | 10.2 | 100 |
| Inferred infection: excess death ratio (95% CI) | 149.3 (147.1–151.3) | 3719.0 (3296.5–3536.3) | Not applicable | |
| Infection fatality risk 2 (IFR) for excess deaths (%) | 0.67 | 0.03 | Not applicable | |
1 The inferred number of infections in the population pre-Omicron BA.1 dominant wave was derived by multiplying the seroprevalence in unvaccinated individuals at the time of the pre-BA.1 serosurveys by the STATS-SA population [14]. The post-BA.1 inferred number of infections was obtained by multiplying the proportion of unvaccinated individuals showing overall serological evidence of SARS-CoV-2 infection (Table S8) between the pre- BA.1 and post-BA.1-dominant wave serosurveys, by the STATS-SA population. 2 The infection fatality ratio was calculated as the inverse of the inferred infection to recorded deaths or excess ratios. All data are from the National Institute for Communicable Diseases daily databases [12] except for weekly excess deaths. Excess mortality from natural causes was defined per and sourced from the South African Medical Research Council [13]; the excess mortality data are reported through 4 June 2022. Other waves are lagged with respect to cases. Consequently, each of the hospitalization, recorded death, and excess death waves has its own cut-off points determining the start and end of the four epidemic waves. † Changes in testing rates, particularly the lower rates during Wave 1 due to constraints in laboratory capacity and prioritization of testing for hospitalized individuals, prevent direct comparisons, especially in terms of case numbers during the first wave in relation to the subsequent waves. Cases include asymptomatic and symptomatic individuals. Cumulative reported cases were sourced from the National Department of Health. ‡ Hospitalization data are from DATCOV, hosted by the National Institute for Communicable Disease, [12] as described previously [10,11]. The system was developed during the course of the first wave, with gradual onboarding of facilities; hence, these data could underestimate hospitalized cases in the first wave relative to subsequent waves. The hospitalized cases include individuals with COVID-19, as well as coincidental infections identified as part of routine testing for SARS-CoV-2 of individuals admitted to the facilities to assist in triaging of patients in the hospital. § Cumulative reported deaths were sourced from the National Department of Health.