Professor warns people ‘will be re-infected every two to four years’

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Mutant variants of the coronavirus could re-infect people every two to four years, a senior scientist has warned.

Paul Hunter, professor of medicine at the University of East Anglia, said it was normal for future strains to emerge and they would not necessarily cause serious illness.

But he warned that “it’s very difficult to predict” because “you never really know what each new variant will do”.

Government advisers are already finding that vaccines are less effective on existing variants, including up to 30% less effective on South African variants.

Highly transmissible mutations first detected in Kent and Brazil are being referred to as ‘variants of concern’ and are also causing a third wave across Europe.

Professor Hunter stressed that many new variants are not of concern, but should be monitored to ensure they don’t derail the roadmap for lifting the lockdown.

Paul Hunter, professor of medicine at the University of East Anglia, said it was normal for future strains to emerge and they wouldn't necessarily kill people.

Paul Hunter, professor of medicine at the University of East Anglia, said it was normal for future strains to emerge and they wouldn’t necessarily kill people.

This morning he told BBC Radio 4’s Today show: ‘We know that new variants are developing, it’s very obvious, and new variants are spreading and becoming dominant.

“Many new variants are disappearing. Not surprisingly, we know from other human coronaviruses that have been with us for decades, if not centuries, that these viruses are gradually drifting.

“ Ultimately, with other human coronaviruses, we expect to be re-infected on average every two to four years or so with the same virus.

“ So we’re likely to see that happen with the coronavirus, and that doesn’t mean we’ll be heading for a lot of very serious illnesses.

“ But it has been very difficult to predict exactly what will happen with the coronaviruses because you never really know what each new variant will do and we have to keep an eye on them and make sure they are not going to undermine it. roadmap. ”

Analysis by SAGE revealed that the South African strain can cause antibodies to decrease in efficacy up to 10 times in people who have been vaccinated or previously infected.

Highly transmissible mutations first detected in Kent and Brazil named as 'variants of concern' and are also causing third wave across Europe

Highly transmissible mutations first detected in Kent and Brazil named as ‘variants of concern’ and are also causing third wave across Europe

While antibodies are not the only part of the immune response against Covid – white blood cells also help – they play a crucial role in fighting infection.

At a meeting on March 12, SAGE said the drop in antibodies “translates into a potential 30% drop in vaccine effectiveness.”

Its examination revealed that the variant was able to infect South African patients who had survived older strains and the data suggested that some immune patients would still catch it.

But the panel of experts stressed that it is still not clear “what the implications are for protection against serious illness.”

The emergence and rise of the South African and similar Brazilian strain abroad has made summer vacations this year increasingly unlikely.

Ministers and their scientific advisers are keen not to allow a huge dumping of imported cases into the UK, which could jeopardize the rollout of vaccines in the country.

The South African strain – officially known as B.1.351 – has three key mutations on its spike protein that help it “ hide ” from the immune system, called E484K, N501Y, and K417N.

Covid uses its peak to cling to human cells, and the current crop of vaccines has been designed to train people’s bodies to recognize this protein.

SAGE said the Brazilian P.1 variant was less of a concern because it has fewer mutations of concern, but it may still be somewhat resistant to vaccines.

The analysis presented to the group looked at studies in South Africa which found that people infected with older strains of Covid were just as likely to catch the new variant as patients who had never had an infection. .

He said this was evidence “ a previous infection, with the 2020 prototype of SARS-CoV-2, did not reduce the risk of subsequent Covid-19 disease, possibly due to variant B .1.351 ”.

India says it has spotted a ‘double mutant’ variant of Covid that spreads more easily and could escape vaccines.

India has claimed to have spotted a ‘double mutant’ variant of Covid that could spread more easily and make vaccines less potent.

Government-backed researchers have detected the strain in samples taken in the western state of Maharashtra.

They suggested that the variant is a hybrid of two different strains of Covid – a rare event that occurs when two viruses merge inside an infected person.

Indian health officials said mutations in the variant signaled a risk of “ immune escape and increased infectivity. ” But they added that the variant had not been detected in high enough numbers to cause the latest wave of infections in India.

The variant, still to be named, presents two main changes which concern the experts. E484Q and L452R – both found on the spike protein, which the immune system targets to fight the coronavirus – are thought to play a role in transmissibility and leakage of antibodies.

However, British scientists told MailOnline today that there is “ no evidence ” to suggest the virus is a “ recombinant variant ”, when two strains merge.

Dr Simon Clarke, a molecular biologist at the University of Reading, said it was more likely to be another variant that randomly spawned these two mutations.

He added: “ We shouldn’t be trying to make this to be anything, just because it’s probably the same thing we’ve seen in other variations, like Brazil’s and from South Africa – all of which have multiple mutations on their peak. protein. I have yet to see any evidence to suggest that it is a recombinant.

Only one hybrid version of the coronavirus has been spotted so far. It was found in the United States and was a mix between the Kent variant and a strain found in California.

Actual data on the strain’s impact on current vaccines was scarce, SAGE said, with only one randomized clinical trial of AstraZeneca directly measuring its effect.

This small study, conducted in adults under 65, showed that the vaccine was only 10% effective in stopping serious illness.

But it was widely criticized at the time as it only affected a small number of young people who had extremely low chances of becoming seriously ill.

Johnson and Johnson’s vaccine, by comparison, was found to be around 64% effective in South Africa – although it didn’t break down specific variants. And a shot done by the US firm Novavax was 60% effective in the country, but again, it did not specifically look at the different types of viruses.

SAGE said: “Overall, this suggests a slight decrease in the efficacy of the vaccine against B.1.351 infection.

“From the analysis of the results of clinical trials and laboratory studies, a tentative conclusion is that when the titers of neutralizing antibodies (NAb) decrease relative to the variants, we can expect a decrease in efficacy. vaccine.

Meanwhile, analysis found that reinfection from the Kent variant was “rare” and “antibodies to previous viruses will continue to provide protection,” as well as vaccines.

It is believed that the South African version be at least 60% more infectious than the original version of Covid, but it does not appear to have an ‘evolutionary advantage’ over the Kent strain, which is why experts believe there has been no huge epidemic in UK.

Public Health England has so far spotted 412 cases of the South African strain in the UK, although it is likely more widespread as authorities are only testing a handful of positive samples.

It comes as aAll truck drivers entering England are subject to mandatory Covid-19 tests to combat the threat of new variants – despite fears the program could disrupt the food supply.

Carriers, border officials and other workers have been exempted from testing when they enter the UK, but Whitehall is set to announce a change this weekend.

Those who arrive will have to take a personalized test once they are in Britain, rather than at the borders, to avoid delays that could lead to empty shelves in supermarkets and shops.

Despite concerns about the delays, Boris Johnson said on Wednesday that the government “ cannot rule out tougher measures ”.

A government source told The Telegraph: ‘The potential impact is difficult to quantify, but there are fears that an incoming testing regime will introduce an additional load that could cause significant friction points. ”

Those staying longer than two days will be required to take a test within 48 hours of arrival and then every 72 hours, with fines similar to penalties of £ 2,000 for travelers who do not pass the test during home quarantine.

Border Force personnel engaged in cross-Channel work and similar arrangements for those working on trains and ferries in the region will be required to pass three mandatory tests per week.

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