Virologists Warn Agaist South Africa and Brasil Mutations
South Africa's and Brasil Wuhan virus strains are resistant to the current vaccines.
Seventeen virologists from South Africa in a scientific paper warned about a threat of new charasterics of the Wuhan virus that has been diagnosed in their country.
The majority of the authors are analysts at the National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg and some are professors from University of Cape Town, University of the Witwatersrand and the Division for Infectious Diseases at Steve Biko Academic Hospital and University of Pretoria.
The virologists analysed the new strains after conducting the anti-body experiment and the vaccine experiment on the new virus.
In conclusion, South African virologists stated that the data on South African and Brasil strains highlight the prospect of reinfection and suggests reduced efficacy of current spike-based vaccines (including the most effective one produced by Moderna).
The authors of the paper designated the new South African strain of Wuhan virus as The SARS-CoV-2 501Y or in short 501Y.
KEY QUOTES FROM THE PAPER
*About a new South African Wuhan virus strain
We, and others, recently described the emergence of a new SARS-CoV-2 lineage in South Africa, 501Y.V2, that included nine changes in the spike protein.
These can be divided into two subsets, one cluster in NTD that includes four substitutions and a deletion (L18F, D80A, D215G, Δ242-244, and R246I), and another cluster of three substitutions in RBD (K417N, E484K, and N501Y). Although the 501Y change has been associated with increased transmissibility, rather than immune pressure, the accumulation of mutations specifically within these two immunodominant regions of spike is highly suggestive of escape from neutralization. Indeed, mutations at 484 have been shown to reduce neutralization sensitivity. Furthermore, mutations in these same regions have also been described in a new variant, which has recently emerged independently in Brazil.
Furthermore, we observe significantly increased neutralization resistance of 501Y.
The SARS-CoV-2 501Y.V2 lineage shows high levels of resistance to convalescent plasma/sera. We next sought to evaluate the effect of 501Y.V2 spike mutations on polyclonal plasma/sera derived from individuals infected with SARS-CoV-2, including individuals who were hospitalised for severe COVID-19. (…) When these same samples were assessed against the 501Y.V2 virus, nearly half (21 of 44, 48%) had no detectable neutralization activity, with only three samples (7%) retaining titres of ID50 >400.
**About a new Brazil Wuhan virus strain
A recently identified lineage in Brazil also has changes at key positions shown here to affect neutralizing antibodies (417T, 484K in RBD and 18F, 20N in NTD - the last mutation adding a glycosylation sequon). Our data suggest that this lineage is also likely to exhibit significant levels of neutralization resistance, making both lineages of considerable public health concern.