A tentative assessment of the changes in transmissibility and fatality risk associated with Beta SARS-CoV-2 variants in South Africa: an ecological study

Pathog Glob Health. 2022 May;116(3):137-139. doi: 10.1080/20477724.2021.2014236. Epub 2021 Dec 20.

Abstract

The circulation of SARS-CoV-2 Beta (B.1.351) variants challenged the control of COVID-19 pandemic. The numbers of COVID-19 cases and deaths and SARS-CoV-2 sequences in South Africa were collected. We reconstructed the variant-specified reproduction numbers (R t) and delay-adjusted case fatality ratio (CFR) to examine the changes in transmissibility and fatality risk of Beta over non-Beta variants. We estimated that Beta variants were 41% (95%CI: 16, 73) more transmissible and 53% (95%CI: 6, 108) more fatal than non-Beta variants. Higher risks of infection and fatality might lead to increasing volumes of infections and critical patients.

Keywords: COVID-19; South Africa; beta variants; case fatality; reproduction number; statistical modeling.

Plain language summary

Impacts The circulation of SARS-CoV-2 Beta (B.1.351) variants, which were firstly reported in South Africa, challenged the control of COVID-19 pandemic.Using the national-wide COVID-19 cases and SARS-CoV-2 sequences data, Beta variants were estimated 41% more transmissible and 53% more fatal than non-Beta variants in South Africa.Higher risks of infection and fatality might lead to increasing volumes of infections and critical patients.

MeSH terms

  • COVID-19* / epidemiology
  • Humans
  • Pandemics
  • SARS-CoV-2* / genetics
  • South Africa / epidemiology

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

ZP was supported by the Natural Science Foundation of China [82073673, 11961071], the National S&T Major Project Foundation of China [2018ZX10715002-004-002, 2018ZX10713001-001], and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). MHW was supported by the National Natural Science Foundation of China [31871340, 71974165], Health and Medical Research Fund, the Food and Health Bureau, The Government of the Hong Kong Special Administrative Region [COVID190103, INF-CUHK-1], and the Chinese University of Hong Kong Grant [PIEF/Ph2/COVID/06, 4054600].