Community Covid testing is to be expanded in two more cities to stem the spread of the South African variant of the coronavirus, as it emerged that the Kent variant was developing some of the same mutations. In a sequence of events illustrating the ever-changing battle faced by ministers in curbing the spread of variants that could be more resistant to vaccines, Matt Hancock used a Commons statement to announce the expansion of efforts to combat the South African strain of coronavirus, feared to be more resistant to existing vaccines. On Monday, the government urged people in eight areas of England to stay at home in almost all circumstances and to expect possible tests after cases of the variant were found in those locations. On Tuesday, the health secretary said there had been 11 cases of “mutations of concern” in Bristol and 32 in Liverpool, and that both cities had been added to areas that will see large amounts of community testing. “As with the variant first identified here in the UK, there is currently no evidence to suggest it is any more severe but we have to come down on it hard,” Hancock told MPs. “Our mission must be to stop its spread all together and break those chains of transmission.” But Public Health England (PHE) said later that the cases in Bristol and Liverpool were in fact previous incarnations of the virus with a mutation known as E484K, previously seen in the South African variant, and in one originating in Brazil. This mutation, as well as one known as K417N and also seen in the South African virus variant, are thought to help the variant evade the body’s immune response, and could affect how well vaccines protect against Covid. PHE said the 32 Liverpool cases showed the original pandemic variant, with the E484K mutation, while in Bristol this mutation had occurred in the UK-originating Kent strain. Both the South African variant and Kent variant contain a mutation called N501Y, which is believed to make the virus more contagious. Experts said the appearance of the E484K mutation in different variants is not a surprise, but is nonetheless a concern. “It shows that the virus is very likely to be adapting to our immune response,” said Prof Lawrence Young, a virologist and professor of molecular oncology at the University of Warwick. One concern is whether current Covid vaccines will prove less effective against new variants. Results from the Novavax Covid vaccine trials, involving two shots of the jab, found that vaccine had 95.6% efficacy against the original coronavirus, 85.6% against the Kent variant and 60% against the South Africa variant – a result Young said still offered good levels of protection. While the E484K mutation could be contributing to the reduced efficacy of vaccines against the South Africa variant, it is unclear if the mutation could also explain the slightly lower efficacy of the Novavax jab towards the Kent variant, not least as very few cases of the latter have been found to contain the E484K mutation. Prof Paul Heath, the principal investigator of the UK arm of the Novavax vaccine trials added further data is needed before it is possible say whether there is truly a difference in vaccine efficacy towards the Kent variant and original virus. “All we are in a position to say is that the efficacy of the vaccine is very high,” he told the Guardian. Hancock told the Commons that the government was working with pharmaceutical firms to see if vaccines needed to be adapted to deal with the variants, and “how they can be brought to use on the frontline as quickly and safely as possible”. Responding for Labour, the shadow health secretary, Jonathan Ashworth, sought clarity on when tougher quarantine measures for overseas arrivals would be brought in, and called for more financial help so people will self-isolate if asked. “We are fighting this virus with one hand tied behind our back, asking the low paid to go hungry in order not to spread the virus,” he said. “Transmission chains won’t be broken without decent sick pay and isolation support.”