WHO says new Covid-19 variants have spread to dozens of countries
New Covid-19 variants that make the virus more contagious and could render vaccine and antibody protection less effective have spread rapidly across dozens of countries, the World Health Organization said on Wednesday.
British Prime Minister Boris Johnson last week also warned that fresh studies had indicated the strain could be more deadly, but the WHO stressed Wednesday that those "results are preliminary, and more analyses are required to further corroborate these findings".
This has raised serious concerns that the variant poses a heightened risk of reinfection, and also could hamper the effectiveness of the growing number of Covid-19 vaccines coming to market.
The WHO said more studies were needed, but stressed that observational studies in South Africa did not indicate an increased risk of reinfection.
It also said that while studies by US biotechnology firm Moderna indicated that its vaccine could potentially be less effective against the variant, "neutralising titres remain above the levels expected to be protective".
That variant, called P1, has raised similar concerns it could be more contagious or cause more severe disease.