The Brazil variant of Covid-19 detected in the UK this week could cause reinfection in up to 61 per cent of people who have already had the virus, a new study suggests.

Research on the P1 variant among people living in the Brazilian city of Manaus detected potentially high levels of reinfection, and signs the variant is more transmissible than the original Covid-19 strain.

On Tuesday, Heatlh Secretary Matt Hancock said the hunt for a missing person infected with a Manaus variant of coronavirus has been narrowed down to 379 households in the South East of England.

To date, six cases of the variant of concern have been found in the UK – three in Scotland and three in England.

A public appeal has been made for one of those people in England to come forward after they took a test in February but left no contact details.

Variant is more transmissible

British experts have cautioned that the study cannot be used to predict what may happen in the UK, and stress that there is no evidence which suggests that Covid-19 vaccines will not work against the new variant.

So far, six cases of the Manaus strain have been found in England and Scotland, and experts are still searching for one of the six people who tests positive.

Blood samples from this latest study, from organisations including Imperial College London, Oxford University and the University of Sao Paulo, suggest that more than 67 per cent of people in Manaus may have had coronavirus by October 2020.

The city then suffered another huge wave of infections at the start of this year, with experts finding that the proportion of Covid-19 cases of the P1 variant grew from zero to 87 per cent in around eight weeks.

The P1 variant was found to be between 1.4 and 2.2 times more transmissible than any other strains in Manaus, and was also found to reinfect between 25 and 61 of protective immunity from previous coronavirus infection.

Dr Nuno Faria, reader in viral evolution at Imperial, said more research is needed on patterns that might occur in other countries to determine how best to protect against it.

He said: We know that vaccines are effective and they can protect us from infection and from disease and death.

“This is a period to be optimistic about the future. The more we know about the virus, the better we’re able to protect against it and I think there’s no concluding evidence to suggest at this point that the current vaccines won’t work against P1.”

Manaus strain low in UK

The Manaus Covid-19 strain has been found in 25 countries so far, but the number of cases in the UK is currently very low.

The current dominant strain of coronavirus in the UK is the Kent variant, but scientists have said none of the variants pose a threat to the vaccination study as yet, giving reason to be optimistic and continue with the vaccine rollout to increase immunity in the population.

Scientists do not so far believe that the P1 variant is more transmissible than the Kent strain, which in itself is more transmissible than the original pandemic strain.

Researchers have said that the current six cases in the UK is a low number, and it is thought that multiple introductions of the variant would be needed for it to become more dominant in the country.

Sharon Peacock, professor of public health and microbiology at the University of Cambridge, said: “At the present time I don’t believe there’s any threat to our vaccination strategy, or likely effectiveness.

“What these variants will mean is that the vaccine manufacturers will be looking to make adaptations to the vaccine so that people can have boosters and some of those adapted vaccines are already being tested in clinical studies.

“So, I think a note of optimism, but also a note that we need to go forward and work with vaccine developers to ensure that over time we have vaccines that are effective for our population.”