Man who had COVID-19 for 400 days finally cured after getting treated with antibodies, study says

• A man carried COVID-19 for more than 400 days.
• The man had mild symptoms, so he did not originally qualify for anti-COVID-19 treatments.
• Doctors finally cured him using anti-COVID-19 antibodies.

A man who had COVID-19 non-stop for more than 400 days was finally cured, a study reporting the case said.

The man, 59, had a suppressed immune system because of a recent kidney transplant. He first tested positive in December 2020 and carried the virus for at least 411 days, The Washington Post reported on November 4.

Genomic testing on the virus showed that the man had the same strain of COVID-19 since the start of his infection, rather than picking up new variants from others.

"Nowadays, everyone is infected with omicron, but when we looked at his virus, it was something that existed a long time ago," Luke Blagdon Snell, a physician studying the evolution of viruses at Guy's and St Thomas' NHS Foundation Trust in the UK, told The Post.

"It was one of those older, early variants from the beginning of the pandemic," he said.

The patient was paucisymptomatic, meaning he did not have the symptoms typical of COVID-19, like cough, fever, or loss of smell. Instead, he had other symptoms that were mild, Snell told Insider in an email.

Because his symptoms were mostly mild, he originally did not fit the criteria to access anti-COVID-19 treatments like antivirals or antibodies, which were reserved for more severe cases.

But doctors finally managed to cure the patient by giving him anti-COVID-19 antibodies in February 2022. The case was reported in the peer-reviewed journal Clinical Infectious Diseases on November 3.

Though the patient's case is characteristically long, it is not the longest-ever reported infection for COVID-19.

In April 2022, the same team reported the case of a patient who had COVID-19 for 505 days before their death, which was the longest documented case at the time, Snell told Insider.

Patients with these types of long-lasting COVID-19 infections tend to have caught the virus at a time when their immune system was weakened. These patients are continuously carrying the virus, unlike patients with long covid who cleared the infection early on, but can have long-lasting symptoms of the disease.

Scientists have been looking at the patients because the virus may be able to mutate inside their bodies during such a long infection.

In another case, reported in June 2021, the virus mutated more than 30 times in a patient whose immune system was weakened by HIV.