The dramatic rise in UK cases of a variant first discovered in India could undermine the countrys roadmap for reopening, scientists are cautioning.
The variant, called B.1.617.2, is one of three closely related variants that were initially detected in India. Public Health England designated it a variant of concern on Friday, acknowledging it appears to be at least as transmissible as the dominant so-called Kent variant in the UK. It is unclear if and to what extent B.1.617.2 can reduce vaccine effectiveness.
Prof Christina Pagel, director of the clinical operational research unit at University College London and a member of the Independent Sage group of experts, speaking in a personal capacity said the rise in B.1.617.2 cases was concerning enough to delay the next stage of the roadmap scheduled for Monday, when a range of restrictions are to be lifted.
According to the Covid-19 genomics UK consortium database which may include duplicates and does not record whether sequences of the variants are linked to travel for sequences up to 7 May, there have so far been 1,393 instances of B.1.617.2, making it the second most common variant in the UK.
Meanwhile, Wellcome Sanger Institutes Covid-19 genomic surveillance data which excludes recent travellers and surge testing specimens suggests that about 6.1% of Covid genomes in England sequenced in the four weeks to 24 April can be attributed to B.1.617.2.
While the Kent variant is decreasing or stabilising, B.1.617.2 is flourishing. In some parts of the country, such as Bolton and Blackburn the variant accounts for over 50% of cases. Andy Burnham, the mayor for Greater Manchester, has said the Joint Committee for Vaccines and Immunisations is considering a request to vaccinate all over-16s in Bolton in response to the rising infection rate.
Pagel pointed out that, while B.1.617.2 numbers are not currently that big, they are doubling every week and this is all within the space of three weeks.
Weve done this so many times waited until things got really bad before we realised we should have acted several weeks ago, she said. So why dont we actually act several weeks ago which is now!
On Thursday, leaked Public Health England documents seen by the Guardian showed that 48 clusters of B.1.617.2 had been identified, including those linked to secondary schools, care homes and religious gatherings.
Recent meeting minutes from the UK governments Scientific Advisory Group for Emergencies (Sage) showed the scientists expected that a variant that substantially escapes immunity or is highly transmissible (more so than the Kent variant) could lead to a wave of infections potentially larger than that seen in January 2021 in the absence of interventions.
Given that so much of our plans for unlocking rely on the protection afforded by vaccination my main concern is that we do not yet know the extent to which many variants escape either naturally acquired or vaccine-induced immunity, said Andrew Hayward, Sage member and director of the UCL Institute of Epidemiology and Health Care.
We know that the vaccine is very effective against the B.1.1.7 [Kent] strain but we also know that the vaccine is less effective at protecting against the variant originating in South Africa. For the variants arising in India we have no real-world data and relatively little laboratory data to assess whether it is likely to evade immunity.
Early data suggested there might be a slight decrease in the effectiveness of vaccines against B.1.617.2 but not as much as against the variant discovered in South Africa, said Deborah Dunn-Walters, professor of immunology at the University of Surrey and chair of the British Society for Immunologys Covid-19 and immunology taskforce, adding that she was feeling very cautious.
Martin McKee, a professor of European public health at the London School of Hygiene & Tropical Medicine, said he and his colleagues are very worried.
There are still many people, especially the young, those in disadvantaged areas, and those from ethnic minorities that are still unvaccinated. I am less concerned about meetings out of doors, as the risks there are low, but I will personally continue to avoid indoor meetings, such as restaurants, even though I am fully vaccinated.
Additional reporting by Nicola Davis and Maya Wolfe-Robinson