Live updates: follow the latest news on Covid-19 variant Omicron
Omicron, the new strain of the coronavirus, may elude the current generation of Covid-19 vaccines, Moderna's chief medical officer has said.
Paul Burton said scientists should know more about the ability of vaccines to provide protection in the next couple of weeks.
"These mutations – at least 30 of them in the spike protein alone, nine of them known to be associated with immune escape, and another 11 are predicted to be associated with immune escape," Mr Burton told the BBC's Andrew Marr Show on Sunday.
"You bring those together [and] I think this is a very concerning virus."
He said the mRNA vaccine platform can be altered “very fast” to respond to new strains.
"If we have to make a brand new vaccine, I think that's going to be early 2022 before that's really going to be available in large quantities."
Pfizer-BioNTech expects lab data within two weeks on the efficacy of its Covid-19 vaccine against the strain and can adapt it within 60 days. The company said it can ship the first batches out within 100 days in the event of an “escape variant”.
Experts have, however, said protection against severe disease and death is expected to hold up, even if vaccines lose some efficiency against the strain.
A researcher for Moderna, who tweets under the name Chise, wrote that there was “NO plausible scenario this will take us back to square one”.
“These vaccines are polyclonal, there are non-neutralising antibodies, and T-cells. Will the vaccines take a hit? Likely, as they do with ALL variants. Will it completely render these useless? Absolutely not," she tweeted.
Omicron was designated a variant of concern on Friday by the World Health Organisation, which said preliminary evidence suggests the strain carries an increased risk of reinfection.
It has rapidly overtaken Delta to become the dominant variant in Gauteng, a province of South Africa, which accounts for the vast majority of cases in the country.
A doctor who raised the alarm about the new variant in the province said on Saturday that healthy patients were developing “unusual but mild symptoms” such as “feeling so tired", a “very high pulse rate” and fever.
“Their symptoms were so different and so mild from those I had treated before,” Dr Angelique Coetzee, a GP who chairs the South African Medical Association, told The Telegraph.
She said her patients were young and healthy and the new variant could still hit older people, or those with underlying health conditions harder.
Epidemiologists have urged caution in interpreting early reports.
Richard Lessells, an infectious diseases physician at the University of KwaZulu-Natal in Durban, South Africa, pointed out the resurgence of cases in Gauteng was very recent and from a low base, with very rapid increases in test positivity rates.
“Most of the early spread was among younger people, with outbreaks in universities likely being amplification events,” he tweeted.
“We would only expect to see the time lag for infections to progress to severe disease and impact on hospitalisations in the next few weeks.”
Doctors have warned they are already seeing an upswing in moderate to severe cases among the young, who are either not at all or only partially vaccinated.
“We’re seeing a marked change in the demographic profile of patients with Covid-19,” Rudo Mathivha, the head of the intensive care unit at Soweto’s Baragwanath Hospital, told an online press briefing.
She said people in their 20s to their late 30s were “coming in with moderate to severe disease, some needing intensive care”.
“About 65 per cent are not vaccinated and most of the rest are only half-vaccinated,” she said.
