COVID-19 viral shedding can last for up to 50 days

A new study reports a case of mild coronavirus disease 2019 (COVID-19) but with an unusually long period of viral shedding, reaching nearly 50 days.

The patient, a middle-aged man, presented with intermittent fever lasting for about 1 week. Other symptoms of COVID-19, such as stuffiness, headaches, chest pain, shortness of breath or diarrhoea, were absent. Close relatives tested positive for the infection a day prior to presentation.

Upon clinical examination, the patient had a body temperature of 36.2 ^oC and laboratory tests found were unremarkable, with normal levels of white blood cells, lymphocytes and neutrophils. Chest computed tomography showed signs of infection, though nasopharyngeal swabs also returned negative for influenza A and B.

The patient eventually tested positive for COVID-19 and, on days 2 to 5 of being hospitalized, developed fevers reaching just under 37.5 ^oC. This normalized by day 6 and, along with other disease indicators, remained stable for the remainder of hospitalization.

Routine testing on oropharyngeal swabs confirmed that the patient was positive for COVID-19 on days 17, 22, 26 and 30. Notably, the positive result persisted beyond this point, indicating viral shedding at days 34, 39 and 43. The final positive test was obtained on day 49.

Given the prolonged infection, the patient was subjected to plasma infusion, leading to high fever which subsided after a day. Subsequent viral tests returned negative.

Future studies are needed to confirm the beneficial effects of plasma therapy on COVID-19 patients and to determine the role that such prolonged viral shedding can have on the course of the outbreak, the researchers said.

This study is a preprint and is not yet peer reviewed.