An interesting report by Talha Burki published in The Lancet February 6, 2021 discusses this topic.
A new consortium is trying to find out whether the variants of SARS-CoV-2 which are emerging will have different clinical effects.
All viruses mutate but the three variants of CoV-2 have raised particular concerns.
NERVTAG, The UK new and emerging respiratory virus threats advisory group published a paper on January 21, 2021 outlining the results from the several preliminary analyses of the new variant B.1.1.7. This variant, which is highly transmissible, was initially identified in the south of England in September 2020 and has now spread to dozens of countries around the world. It carries 17 mutations in its genome, including eight in the spike protein, which forms the basis of the three COVID-19 vaccines that have been licensed in the UK.
NERVTAG concluded that there is a realistic possibility that infection with B.1.1.7 could be associated with an increased risk of death, compared with infection with the parental virus. The group, however, stressed that its assessment was based on limited preliminary data and even if the results were confirmed, the overall risk of death would still be low.
Another extremely infectious variant, P.1, has been circulating in Brazil since the middle of 2020. This variant has been implicated in the surge of infections that has struck by Manaus, in the Brazilian Amazon, leaving the healthcare system on the brink of collapse.
B.1.351 was first detected in South Africa late last year. On January 25, Moderna said that their in vitro studies indicated that its vaccine would be effective against B.1.351 and B.1.1.7. However, the South African variant was associated with a substantial reduction in neutralising antibodies.
Pfizer has revealed that laboratory tests suggested that its vaccine would work against B.1.1.7. Studies have not been peer reviewed.
Both companies, however, have said they are investigating booster shots to protect against variants of SARS-CoV-2.
A newly formed consortium, the G2P–UK National Virology Consortium has a remit to look at variants that will influence the pandemic. They are examining how the mutations affect the transmissibility of the virus, the severity of the disease, and the effectiveness of vaccines and treatments.
The UK has generated almost half of the approximately 400,000 genomic sequences of SARS-CoV-2. G2P Consortium will look at whether the variants have different properties, whether they are replicate in distinctive ways, and whether they escape neutralising antibodies from people who have previously been infected or from others who have been vaccinated.
The Brazilian, UK and South African variants do not seem to be associated with more severe disease. Massimo Palmarini, co-lead of the new consortium, remarked that the goal was to arrive at a point at which the researchers could identify mutations of concern. The spike protein is crucial, given its interaction with the immune system and
its role in the vaccines, but the viral phenotype can also be driven by mutations in other proteins.
Professor Martin Hibbard from the London School of Hygiene and Tropical Medicine stated that the existing variants have evolved in relation to transmissibility, rather than in response to the vaccines. He added that adjusting mRNA vaccines such as the Pfizer and Moderna products where necessary should be relatively straightforward.
The consortium’s aim is to study the epidemiological data with laboratory experimental data on strains and mutations with an ability to predict what the virus will do. This is clearly essential when countries around the world prepare to roll out the COVID-19 vaccines.
Dr Paul Ettlinger
BM, DRCOG, FRCGP, FRIPH, DOccMed