Scientists have announced that the world’s longest known Covid infection lasted 505 DAYS –

A Covid patient battled the same infection for nearly 18 months in what is believed to be the longest known case in the world.

The unidentified British patient who eventually died was severely immunocompromised, scientists say.

Doctors did not reveal what the patient’s condition was, how old he was, or whether he had been vaccinated.

But they studied nine different patients with weakened immune systems from organ transplants, HIV, and cancer.

Researchers from King’s College London and Guy’s and St Thomas’ NHS Foundation uncovered the cases.

Four patients died and two required antibody and antiviral therapies to eradicate the infection. Two people eventually recovered without treatment.

The ninth patient had the same Covid attack they had received 412 days earlier.

If they fail to clear the virus at the next follow-up, they will eclipse the other patient’s 505-day record.

In total, nine patients had battled Covid for an average of 72 days before they recovered, died or finished the study.

The team also saw one case of ‘hidden’ infection.

This is defined when a person is believed to have recovered and tested negative, but is later found to still harbor the virus.

This phenomenon – unlike ‘prolonged Covid’ – is observed in other pathogens such as Ebola and hepatitis B.

People who are immunocompromised are particularly vulnerable to Covid as their body’s natural defenses are much weaker.

This is why the NHS says they should have taken four hits by now.

They have a hard time recovering because of their weakened immune systems, meaning they keep the virus longer.

This can give the virus time to mutate in their bodies, potentially leading to a new variant that can infect others.

Some experts suspect that this is the reason for the emergence of a super-mutated variant of Omicron that took the world by storm in late 2021.

The UK team’s findings support this theory, with regular genetic sampling from patients revealing that five developed at least one mutation seen in known Covid care strains.

One patient’s virus developed a total of 10 mutations, which also developed separately in Alpha, Gamma, and Omicron variants.

Study author Dr. Luke Snell said there is evidence that new Covid variants can emerge in immunocompromised patients.

However, he added that it is not known whether this is the origin of tribes such as the Omicron.

“However, it is important to note that none of the individuals in our study developed new variants that became common variants of concern,” he said.

Co-author Dr Gaia Nebbia said the study highlights the importance of developing treatments to help immunocompromised patients recover from Covid.

“Immunocompromised patients with persistent infections have poor outcomes and new treatment strategies are urgently needed to cure their infections,” he said.

“This can also prevent variants from appearing.”

The patient with the latent Covid infection tested negative for the virus several times before showing symptoms again a few months later.

Genetic analysis of this virus showed it to be a version of the Alpha variant, which became extinct in the UK when symptoms returned.

This suggested that the virus remained dormant in the patient’s body for months after initial infection, the authors wrote.

Patients were recruited between March 2020 and December 2021 and tested positive for the virus for at least eight weeks.

Most people recover from Covid infection within weeks, according to the NHS.

The researchers presented their findings at the European Congress of Clinical Microbiology and Infectious Diseases in Portugal.