Patients could catch two COVID-19 strains at once, scientists say, after reports of dual infection from Brazil.
And it could lead to even more new variants evolving, with abilities to dodge vaccines and spread easier.
Amid growing concern of new variants popping up globally, doctors said they were the first to describe the phenomenon of a coronavirus coinfection.
Two people in their 30s tested positive for two Brazilian strains known as P.1 and P.2.
The patients were infected in late November with the P.2 variant of coronavirus identified in Rio.
They simultaneously tested positive for the P.1 variant of the virus which evolved separately in Manaus, which was confirmed with laboratory tests.
The patients’ symptoms were reportedly mild, with a dry cough in one case, and coughing, sore throat and headache in the second. They did not need hospital care.
Dr Fernando Spilki, a virologist at Feevale University in Rio Grande do Sul state and lead researchers, said dual infection was only likely to happen when different viruses were circulating in high numbers.
Since November, Brazil has been fighting a steep second wave of infections, routinely recording over 1000 deaths per day in 2021.
Hospitals are at capacity in the country amid a resurgence of cases caused by new strains of the virus.
The case studies reported by Dr Spilki and colleagues raise concerns among scientists that coinfection could speed up the development of new mutations, and therefore new variants of the coronavirus.
“These co-infections can generate combinations and generate new variants even more quickly than has been happening,” Dr Spilki said, according to Reuters.
“It would be another evolutionary pathway for the virus.”
One of the ways mutations evolve is by coinfection of the same cell.
This is thought to be one way the new UK strain of coronavirus picked up a more worrisome mutation characteristic of the South African and Brazil variants.
But scientists admitted this was a “rare” way for coronaviruses to gain mutations.
Speaking on the back of the research – which has not been peer-reviewed – scientists said it was already the case that people get infected with two strains of a virus at once.
“It is perfectly possible for a child attending a primary school to get infected with one variant of Covid-19, and an older sibling to attend secondary school and get infected with a different Covid-19 variant – and for both children to bring their viruses home to infect each other – and their parents with both variants,” Dr Julian Tang, a professor in respiratory sciences at the University of Leicester, told MailOnline.
Professor Keith Neal, an infectious diseases expert at the University of Nottingham, said if there was a lot of transmission “you can pick up two different viruses around the same time”.
But when one strain is predominant, that is unlikely.
In the UK, the Kent variant has quickly become the most prevalent strain, however, there are others still in circulation.
It comes as ministers race to avoid another new variant from South Africa wreaking havoc, after more than 100 cases have been identified in the UK since December, at least 11 of them with no travel links to South Africa.
The Health Secretary Matt Hancock has vowed to “come down hard” on the variant with the introduction of a mass testing scheme.
A door-to-door testing blitz on up to 350,000 people was launched this week in areas where the South African strain is feared to be transmitting within the community.
Meanwhile, the UK‘s Kent COVID strain has acquired a mutation similar to the South African variant, and could resist jabs, official reports revealed.
Public Health England have detected 11 cases in Bristol where the Kent variant has gained the E484K mutation, which helps the virus to “escape” immune response.
A cluster of 32 cases in Liverpool also have the same mutation but relate to the original strain of coronavirus that has been around since the start of the pandemic, from Wuhan.
Mr Hancock said yesterday the new variants pose “renewed challenges” as the UK makes great strides in its vaccination rollout.
Dr Tang said the mutation was a “worrying development, though not entirely unexpected”.
Regarding the E484K mutation seen in the Kent variant, Dr Jonathan Stoye, from the Francis Crick Institute, said the PHE report suggests the UK variant is now independently acquiring the E484K change.
“From a virological standpoint, appearance of new variants by mutation during replication cannot be considered surprising,” he added.
“Whether this change will provide significant growth advantages for the novel virus causing it to predominate remains to be seen.”
New variants threaten resistance to vaccines, and could also increase the risk of reinfection in people who have previously recovered from Covid.
Experts in Brazil reported in January that an unnamed 45-year-old nurse came down with the P.1 variant in October – five months after she recovered from an older strain of Covid-19.
Her symptoms were worse the second time she caught the virus, as she developed breathing difficulties, shortness of breath, muscle pains and insomnia.
The P.1 variant, which has the E484K mutation, has not yet been detected in the UK.
P.2 has been detected in the UK, but experts say it is no cause for concern.
Researchers from the Oswaldo Cruz Foundation, a science institute in Rio de Janeiro, said that “viral evolutions may favour reinfections”.
Public health experts believe current vaccines will still be effective against new strains, although at a lower level, and are good at preventing severe disease.
This story originally appeared on The Sun and has been republished with permission