Hundreds of thousands of people are being urged to get tested to try and stamp out a “concerning” strain of the virus which causes Covid-19.
One expert said “none” of the vaccines are as effective against the South African variant – though studies suggest that the jabs still prevent severe disease and death.
Rapid surge testing has been deployed in four London boroughs – with all adults in Wandsworth and Lambeth being asked to get a test and people in specific areas of Barnet and Southwark also invited to perform at test.
The Prime Minister’s official spokesman said Boris Johnson took the situation “very seriously” and recommended for everyone to “take up that invitation” to get tested.
Meanwhile, the Government is considering making vaccination of people working in care homes with older adults mandatory.
Concerns have been raised about the low take-up of the vaccine in many care homes.
The Department of Health and Social Care launched a consultation on making Covid-19 vaccination a “condition of deployment” for care home staff.
Commenting on surge testing, Professor Anthony Harnden, deputy chairman of the Joint Committee on Vaccination and Immunisation (JCVI), told Good Morning Britain: “From a vaccine point of view the South African variant is of concern.
“We know from studies that none of the vaccines are as effective against the South African variant – though the vaccines still prevent against severe disease and death even with the South African variant.
“The problem is, they may not protect against infection which allows infection to transmit, and if we allow transmission through the community in large numbers with high infection rates then we could see other variants emerging.”
Data up to April 7 suggests there have been 544 cases of the South African variant found in the UK in total, including 533 gnomically confirmed cases and 11 probable cases.
Surge testing involves swabbing people without any symptoms of the virus to see if they are infected using tests which are assessed in a laboratory setting – also known as a PCR test. These are different to the 30 minute lateral flow tests.
Population data show that more than half a million adults live in the areas being asked to take tests as part of the surge testing programme.
Health officials said that the surge testing in Finchley, Barnet, was launched after a single case of the South African variant was identified.
The Department of Health and Social Care said that genomic sequencing indicates that the case is “not linked” to the cluster identified in South London.
In other developments:
– A “mix and match” trial assessing the use of two different types of Covid-19 vaccines in the same person was extended.
– Office for National Statistics (ONS) figures suggest that across the UK, half the adult population would test positive for Covid-19 antibodies, which means they have either been infected or they have been vaccinated.
– The number of vaccine doses administered in the UK has passed 40 million, of which nearly eight million are second doses.
– Denmark announced that it will cease to use the Oxford/AstraZeneca Covid-19 jab after concerns were raised about a very rare side effect of blood clots.
– People aged 45 and over in England are being invited to make appointments for their vaccination.
Meanwhile, Prof Harnden urged people “not to go wild” and said people should not behave in the same way as they did before the pandemic.
Mr Johnson said on Tuesday that although vaccines had helped, lockdown restrictions had done “the bulk of the work” in reducing Covid-19 infections.
And he warned that the easing of lockdown restrictions will “inevitably” lead to more infections and deaths.
Asked about the remarks, Prof Harnden told BBC Breakfast: “I think he’s probably concerned, as I am, about the scenes in London that we saw of people actually enjoying the outside, pubs and then the crowded spaces – well, of course what that will do is push infection rates up.
“And new variant strains such as the South African strain – we really don’t want that to become prevalent in this country because of course the vaccines don’t work quite as well (against it).
“We will all want to get our lives back, we all want to enjoy ourselves again, but we must be cautious and do this slowly. Otherwise we’ll get back to square one.”
But the Prime Minister’s spokesman said there is “nothing to suggest” that the vast majority of the public “aren’t behaving responsibly” since the lockdown was eased this week.
It comes as the DHSC said that almost half of care homes for older residents in England are not providing a minimum level of protection due to poor uptake of the vaccine.
As it launched its consultation on making it compulsory for staff in such care homes to have a jab, the DHSC said that experts from the Scientific Advisory Group for Emergencies (Sage) have estimated that 80% of staff and 90% of residents need to be vaccinated to provide a minimum level of protection against Covid-19 outbreaks.
But DHSC said nearly half of care homes for older residents in England are not meeting this threshold.