A man who became the first person known to be infected with COVID-19 twice had two separate strains of the virus, sparking fears it has mutated.
The otherwise healthy 33-year-old man from Hong Kong didn’t experience any symptoms during his second bout.
Dr Norman Swan appeared on the ABC’s 7.30 to explain the man’s second positive test indicated the infection could be unrecognisable even in a body that had already beaten it once.
‘There are two possible reasons for reinfection,’ Dr Swan said, describing the man as a ‘worrying case’.
‘One is that the person’s immunity has waned. The other is that the virus has mutated so much that the immune system doesn’t recognise it. Both have implications for the future of this pandemic and its control.’
Passengers wearing protective masks collecting baggage after arriving on a Jetstar flight from Melbourne at Sydney Airport
But Dr Swan said the ‘good news’ to come from the second infection was that the man never felt sick the second time around.
‘That might mean that whatever immunity he had left saved him from COVID-19 disease which is actually what most vaccines are being designed to do,’ he said.
Both test results were analysed by Dr Kelvin To, a clinical microbiologist from the University of Hong Kong.
Dr To appeared on the ABC on Monday night to explain he and his team ‘found they were different versions of the coronavirus, confirming it was a second infection’.
The alternative would have been that he’d never recovered from his first infection.
The 33-year-old first tested positive to the deadly respiratory virus in late March, before testing positive again four-and-a-half months later at an airport in Spain on the way home from a trip away.
Travellers are temperature tested by health officials after arriving on a Qantas flight from Melbourne to Sydney on July 7
Dr To appeared on ABC on Monday night to explain that he and his team ‘found they were different versions of the coronavirus, confirming it was a second infection’
Dr To described the man’s asymptomatic second case as ‘reassuring’.
‘We know that from many studies, patients (who) have the immunity, actually it is not as good … a few months after the first infection, especially for the decreasing antibody levels, so that is one possibility,’ Dr To said.
‘I am also glad to see this patient had a very mild or asymptomatic infection in the second episode. That is reassuring, in some sense, but remember this is only one patient.’
A woman wearing a mask as a preventative measure against the coronavirus in Sydney at the height of the first wave
Dr Swan (pictured) said the ‘good news’ to come from the second infection was that the man claimed he never felt sick the second time around