Detections of the South African variant of Covid have been found in dozens of people in two London boroughs – causing a surge in mass testing.
What are the authorities doing to contain this new outbreak, and which vaccine is most effective against the variant? Here’s what you need to know.
Which vaccine works against mutant Covid strain?
The Covid vaccine manufactured by Pfizer and BioNTech appears to be 100 per cent effective in protecting against the South African variant, according to research published by Pfizer/BioNTech in April.
The pharmaceutical giant said its findings show the vaccine is 100% effective in preventing Covid-19 cases in South Africa - where the South African variant is now dominant.
Among 800 people in South Africa, nine cases of the South African variant of Covid were observed - all in the group were not given the vaccine.
Of the nine people who fell ill, analysis showed they had six of nine known South African variant strains.
The 800 people were part of a larger, phase three clinical trial also showing the vaccine was highly effective even after six months.
Ugur Sahin, BioNTech's chief executive, said the trial numbers "provide the first clinical results that a vaccine can effectively protect against currently circulating variants, a critical factor for herd immunity, and end this pandemic for the global population”.
Where have the new South African strains been found in the UK?
Dozens of cases of the South African variant of Covid have been found in two London boroughs.
Some 44 confirmed cases of the variant have been found predominantly in Lambeth and 30 probable cases have been identified in neighbouring Wandsworth, the Department of Health and Social Care (DHSC) said.
For those who do test positive, a self-isolation support service is available, which includes payments of up to £500 for residents on low incomes.
What is being done to stop the spread of the virus?
Eight extra coronavirus testing facilities are being set up in Lambeth and Wandsworth.
Lambeth Council said it is “vital” that residents get a test, whether asymptomatic or not, to help control the spread of the virus.
People aged 11 and over who live, work or travel through those areas are being urged to take a polymerase chain reaction (PCR) test, on top of using twice-weekly rapid testing.
Ruth Hutt, director of public health for Lambeth, said: “It is vital that all Lambeth residents take an asymptomatic PCR test so that we can identify all cases in order to stop the spread of this variant of concern.
“Alongside taking a PCR test, we are asking everyone who lives and works in the borough to continue following the guidance in place to stop the spread of Covid-19.
“That includes limiting your contacts with other people, washing your hands regularly and thoroughly, keeping your distance and covering your face.
“If you test positive for Covid-19 via a PCR test or rapid lateral flow test it is crucial that you self-isolate so you don’t pass on the virus, and support is available to help you do that.”