Young people discharged after being treated for COVID-19 may retest positive: Study

According to the researchers, 38 of 262 subjects – all of whom were observed for at least two weeks – retested positive, which was almost identical to the proportion – 14 per cent – found in a study conducted in late February by health authorities in southern China’s Guangdong province.

However, research conducted last month by a team from Tongji Hospital in Wuhan – the central China city at the epicentre of the initial outbreak – returned a positive retest figure of just three per cent.

A study by scientists from China and the United States found that 14.5 per cent of people discharged from hospital after being treated for Covid-19 later retested positive for infection.

According to the researchers, 38 of 262 subjects – all of whom were observed for at least two weeks – retested positive, which was almost identical to the proportion – 14 per cent – found in a study conducted in late February by health authorities in southern China’s Guangdong province.

Of the 38 patients who retested positive after discharge, just one was aged over 60, while seven were under 14, it said.

Also, of the 38, only “a small number reported a mild cough and chest tightness, which was not worse than before”, while none experienced a fever, it said.

The researchers also tested 21 people with whom the 38 subjects had been in close contact and they all came back negative for the coronavirus.

Despite their findings, the researchers said that because of discrepancies in the results found with different test kits, they had not ruled out the possibility that people who had recovered from Covid-19 might become carriers.

The researchers found that 18 of 24 patients who returned a negative result using a commercially available test kit – known as an RT-PCR – actually tested positive when subjected to more “sensitive” tests, according to Feng Zhang from MIT who was a co-author of the study.