Two more Covid-19 variants encountered in SA but experts are unruffled

This undated electron microscope image made available by the US National Institutes of Health in February 2020 shows the virus that causes Covid-19. Picture: AP

This undated electron microscope image made available by the US National Institutes of Health in February 2020 shows the virus that causes Covid-19. Picture: AP

Published Mar 7, 2021

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The country now has to contend with two additional Covid-19 variants, but experts maintain that they were less concerning than the country’s dominant variant. They would continue to monitor them and be on the lookout for more.

The A.23.1 variant dominating infections in Uganda and Rwanda and the 501Y.V1 or B.1.1.7 variant driving infections in the UK were discovered in the country.

Professor Tulio de Oliveira, director of the Kwazulu-Natal Research Innovation and Sequencing Platform, said the first South African sequence of A.23.1 was sampled in Nelson Mandela Bay on January 11 and was deposited to GISAID - a platform headquartered in Germany that enabled rapid and open access to epidemic and pandemic virus data.

Richard Lessells, KRISP's group leader and infectious diseases specialist, said as international borders have opened up again, it was likely other variants would be imported into the country.

“We will pick them up through the Network for Genomic Surveillance - South Africa or NGS-SA. We have already picked up the case with the B.1.1.7 variant,” he said.

Lessels said A.23.1 had about four to five mutations in the spike protein compared to the seven to nine spike mutations in 501Y.V2.

“None of the specific spike mutations are common between the two variants. Some of the mutations in A.23.1 are at positions that could affect the function of the virus, but we don't have a good understanding of this at the moment. So we will need more research to really understand the significance of the constellation of mutations in the A.23.1 variant. We don't know how the variant will interact with the vaccine and this research still needs to be done. But none of the mutations in A.23.1 have been clearly linked with escape from neutralising antibodies. A.23.1 is currently not a concern in terms of driving a resurgence.”

Infectious diseases epidemiologist Professor Salim Abdool Karim and co-chair of the Ministerial Advisory Committee said: “A.23.1 is considered a variant of interest, not a variant of concern. Globally, there are currently only three variants of concern; the B1.1.7 described in the UK, the 501Y.V2 discovered by the KRISP team that is the dominant local variant and the P1 traced back to Brazil,” he said.

Karim said since B.1.1.7 was discovered in December, it was learnt to be between 46% to 72% more transmissable and three UK studies showed that the death rate in areas with the B1.1.7 variant was between 25% to 35% higher - in comparison to earlier Covid-19 iterations.

“But with all that said the 501Y.V2 variant discovered locally remains more concerning than the B.1.1.7 and A.23.1 variants as it has immune response evasive mutations,” said Karim.

Minister of Higher Education, Science and Technology Blade Nzimande, with the backing of data and scientists, said that those infected with 501Y.V2 showed a developed immune response that prevented infection from other variants.

The scientists were De Oliveira and the KRISP team, Professor Koleka Mlisana, an executive from the National Health Laboratory Service, Professor Penny Moore from the National Institute for Communicable Diseases and Alex Sigal from the Africa Health Research Institute.

On Friday, Deputy Health Minister Joe Phaahla briefed the parliamentary health portfolio committee with a vaccine rollout update and said more variants with more mutations would emerge but government hoped they would be less devastating than 501Y.V2.

“This is an invisible enemy. This is the nature of viruses, they mutate. There might be more difficult variants that could provide further challenges, it is going to happen. Scientists tell us that the normal trend is for viruses to mutate and then become less lethal. So we are hoping future variants will be less lethal.”

Speaking at a webinar hosted by the National Press Club and the GCIS, Health Minister Zweli Mkhize said there was still no clear-cut model to predict the third wave but it could occur during late April or early May.

“We may not be able to predict accurately when the next surge is coming, it may come when we have huge movement of people during public meetings or the Easter holidays when people are travelling.”

Sunday Tribune