According to a story from BioSpace, a case study of a 33 year old man has confirmed that it is possible for humans to get infected with the virus responsible for COVID-19 twice, suggesting that immunity may not last very long in recovered patients. While there have been unverified reports of reinfection from all over the world, this case report seems to definitively confirm the possibility of patients getting the virus more than once.

COVID-19: Round Two

The man in question was first hospitalized for the coronavirus in March. On August 15th, at the Hong Kong airport, the subject tested positive for the virus again. At this juncture, he is not displaying any symptoms. The research team conducted a genetic sequence on the viral samples collected from the patient during his positive tests. The scientists soon recognized significant genetic differences between the two samples, which strongly suggested that he had been infected again as opposed to his original case not resolving. Viruses mutate on a regular basis.

Kelvin To of the University of Hong Kong, one of the study authors, says that the findings suggest that at least some patients do not gain permanent, life-long immunity to the disease after recovery. The genetic samples matched closely to common samples from early spring (in the case of the first infection) and samples more recently found in Europe, which is where the subject had been traveling from. The blood test also did not reveal the presence of antiviral antibodies, which would normally be expected in an individual that was infected and had recovered.

Implications

The findings have significant implications for the development of vaccines, which may not be the resolution to the pandemic as originally thought; a vaccine developed with a viral strain that may have been up to date at the time may soon be rendered useless if patients are still vulnerable to more recently mutated strains. However, the London School of Hygiene & Tropical Medicine’s Brendan Wren says that the case shouldn’t be a cause for giving up on vaccines.

After all, cases of reinfection, while clearly possible, seem to be fairly rare and it is also noteworthy that the patient has not displayed symptoms with the second infection. Nevertheless, the case represents an important finding as the scientific community continues to learn more about the unusual COVID-19 virus.