Covid-19 virus variants and their impact on vaccines

North-West University (NWU) academic Dr Hazel Tumelo Mufhandu presented a public lecture on Covid-19 virus variants and their impact on vaccines as part of a National Science Week webinar series on 2 August 2021.

This year the National Science Week theme is “Making it possible through science".

According to Dr Mufhandu all viruses, including SARS-CoV-2 which causes Covid-19, change over time, and most of these changes have little to no impact on the virus's properties.

“However, some changes may affect the virus's properties, such as how easily it spreads, the associated disease severity, or the performance of vaccines, therapeutic medicines and diagnostic tools,” she said.

“Among these properties, the performance of vaccines and the virus's ability to evade vaccine-induced immunity would likely be the most concerning, as there is emerging evidence of reduced neutralisation of some SARS-CoV-2 variants by post-vaccination serum.

“However, a greater understanding of correlates of protection is required to evaluate how this may impact vaccine effectiveness,” Dr Mufhandu added.

In late 2020, the emergence of variants that posed an increased risk to global public health prompted the characterisation of SARS-CoV-2 variants into specific variants of interest (VOIs), variants of concern (VOCs) and variants of high consequence (VOHC). This was done to prioritise global monitoring and research, and ultimately to inform the ongoing response to the Covid-19 pandemic.

“The established nomenclature systems for naming and tracking SARS-CoV-2 genetic lineages considered an easy to pronounce and non-stigmatising labels for VOI and VOC using letters of the Greek alphabet, such as Alpha, Beta, Gamma, Delta, which are easier and more practical for discussion purposes.

“Tracking the emergence of these virus variants will help to guide the implementation of targeted control measures. An important part of this process will be the preparation of updated vaccines tailored to emerging antigenic variants that are cross-reactive against all circulating variants,” said Dr Mufhandu.

Expert in medical virology

Dr Mufhandu is a medical virologist, senior lecturer and deputy group leader of the subject group Microbiology at the NWU. In addition to Covid-19 research, she conducts research on HIV/Aids and hepatitis.

She has co-authored several peer-reviewed scientific publications and reviewed dissertations and theses from various universities, along with grant applications and manuscripts and book chapters for academic publishers. Among them are Elsevier – the publisher of journals such as Heliyon and the Journal of Water and Health – and CRC Press in the Taylor & Francis Group.

Dr Mufhandu has also been the recipient of various awards. These include the Clinical Excellence Merit Award at the 6th South African AIDS Conference, a presentation distinction at the 5th International AIDS Society Conference, and Namibia top publication of the year (2004). She serves on the advisory committee of the South African Health Products Regulatory Authority for Quality Manufacturing and Control of Complementary Medicine.


Dr Mufhandu

Submitted on Tue, 08/17/2021 - 12:38