Can you catch coronavirus twice? The question grows relevant over the past weeks, after people have been reportedly been infected by covid-19 several weeks after their recovery. As searchers thought about relapse, medical literature has been reported cases of SARS-COV-2 coronavirus reinfection.
A second case has been reported this week, in a young 25-year-ol man, studied by searchers from the Nevada university (Las Vegas) and currently SSRN pre-printing for British weekly medical magazine The Lancet.
Living in Reno, Nevada, the man has tested positive on April 18 in a testing campaign organized by the county of Washoe. Back then, he had a sore throat, cough, headaches, nausea and diarrhea for 3 weeks. The man has been put in self-isolation and showed no symptoms anymore on April 27. The medical staff performs two PCR tests on May 9, both tests come back negative: the virus seems to be no longer in the body of the man.
But on May 28, the man feels ill again and consults his doctor. He once again has fever, headaches, feels dizzy, is coughing, has nausea and diarrhea. His doctor prescribes him a chest roentgenogram he has on May 31. Five days later, on June 5, he sees his doctor again who notices hypoxemia, that is to say low oxygen levels in his blood. The man goes to the ER to get oxygen and gets a PCR test: the test returns positive. In the meantime, the patient starts having muscle pains, and cough, as well as difficulty breathing, and doctors decide to perform another chest roentgenogram. It shows diffuse pulmonary abnormalities (interstitial bilateral opacities in that very case) remining of pneumonia.
Thus, doctors draw a blood sample on June 6 that shows there are IgM and IgG antibodies directed against SARS-CoV-2, that shows there is a recent coronavirus re-infection.
To be sure of it, doctors decide to sequence samples from the PCR tests performed in April and June. If the virus that has been infecting the young lad in June comes from the same strain, the “clade 20”, there are differences in comparison with the virus that infected him back in April. According to authors, it could not be the same virus that would have been put out and muted in the body of the individual before waking up and resurging.
This observation is the second one to be brought up in international medical literature, after a case reported two days earlier in Clinical Infectious Diseases by a team from Hong Kong.
They insist on the fact that today, we still do not know how frequent this phenomenon can happen and it obviously cannot be determined based on only one case. It “may represent a rare event” they write. Careful though, even though the piece is online, it has not been proof-read and has not been officially released in body of documents.