LONDON (REUTERS) – The transmissibility advantage of the B16172 variant first identified in India might be a little lower than first feared, a leading British epidemiologist said on Wednesday (May 19), but vaccines might be less effective at limiting its spread.
Prime Minister Boris Johnson on Friday warned that the emergence of the variant might derail his plans to lift England’s lockdown fully on June 21.
Mr Johnson said that if the variant was only marginally more transmissible than the dominant Kent variant, then easing could continue as planned, but a significant transmissibility advantage might force him to reconsider the plans.
“There’s… a glimmer of hope from the recent data that, whilst this variant does still appear to have a significant growth advantage, the magnitude of that advantage seems to have dropped a little bit with the most recent data,” Dr Neil Ferguson, an epidemiologist at Imperial College London, told BBC radio.
Dr Ferguson, who is a member of the government’s Scientific Advisory Group for Emergencies, said that it was tricky to immediately determine by how much the B16172 outcompetes the Kent variant, and more data was needed.
He said the initial rapid growth of B16172 had been among people who had travelled and who had a higher chance of living in multi-generational households or in deprived areas, and the speedy transmission might not be replicated in other settings.
Dr Graham Medley, also a member of SAGE and a professor of disease modelling at the London School of Hygiene and Tropical Medicine, said that while the variant was growing quickly in some places, “we haven’t yet seen it take off and grow rapidly everywhere else”.
“One of the key things we’ll be looking for in the coming weeks will be: how far does it spread outside of those areas,” he told Reuters.
Dr Ferguson added that though there was a “good deal of confidence” that vaccines will protect against severe disease from the variant, B16172 might be able to spread more easily among vaccinated people.
“There’s some hints in the data there’s reduced vaccine efficacy against infection, against transmission,” he said.
“But we really have to wait as more data is gathered to be definitive about that.”