Patient had Covid infection for 505 days
UK doctors may have found the longest Covid infection on record after a patient tested positive to the virus for more than 16 months.
The patient, who cannot be named for privacy reasons, had the virus for exactly 505 days before tragically dying in hospital in 2021.
Despite constant check-ups and care, the patient could not overcome the infection even when treated antiviral drugs.
The patient, who had underlying health conditions, was part of a larger study of long-lasting Covid.
The study from King’s College London and Guy’s and St Thomas’ NHS Foundation Trust involved nine patients who tested positive for at least eight weeks. All participants had underlying health conditions which weakened their immune systems. Some had previously had treatments for cancer or organ transplants.
For the nine patients involved their infections persisted for an average of 73 days. Two had the virus for over a year.
The study highlights the reality that immunocompromised people are still highly susceptible to the virus. The findings will be presented at the European Congress of Clinical Microbiology and Infectious Diseases medical conference this week.
One of the doctors involved in the study, Dr Luke Blagdon Snell, told BBC News that while prolonged Covid was rare it was important as it might create conditions for the creation of new variants. However, none of the nine patients tested had spawned new variants.
“The virus is still adapting to the human host when people are infected for a long time. It might provide an opportunity for Covid to accrue new mutations,” he said.
“Some of these patients that we have studied have mutations that have been seen in some of the variants of concern.”
Earlier this year another study revealed a 22-year-old South African woman with untreated HIV had been infected with SARS-CoV-2 for nine months. In this time the virus had accumulated more than 20 additional mutations.
Researchers determined that she was initially infected with the Beta variant of Covid-19 – which, as with Omicron, was first detected in South Africa – and that genomic analysis of multiple swabs confirmed “persistent infection over at least nine months rather than reinfection”.
“Over this period, the virus acquired at least 10 mutations in the spike glycoprotein and 11 mutations outside spike over and above the lineage-defining mutations for Beta,” they wrote.
Some of the additional mutations were similar to those seen in the Omicron and Lambda variants, allowing the virus to evade neutralising antibodies.
The researchers cautioned that there was “no evidence that the evolved variants from this case successfully spread into the general population”.
Prolonged Covid is very different to long Covid.
More Coverage
Similarly to the South African case, researchers in the UK study would analyse the genetic code of the virus in order to tell that it was the same strain and not a case of reinfection. Genetic sequencing is able to detect changes and mutations in the virus over time.
“In long Covid, it’s generally assumed the virus has been cleared from your body but the symptoms persist,” Dr Snell said.
“With persistent infection, it represents ongoing, active replication of the virus.”