A Hong Kong case of Covid-19 reinfection does not undermine the need to develop an effective global vaccine, a Dunedin researcher says.
Hong Kong scientists have reported the case of a healthy man in his 30s who was reinfected with Sars-CoV-2, the virus that causes Covid-19, only four and a-half months after his initial illness.
Those researchers said genome sequencing showed the two strains of the virus were different, making this the world’s first proven case of Sars-CoV-2 reinfection.
The World Health Organisation has since warned people not to form conclusions based on the case of only one patient.
Associate Prof James Ussher, of the University of Otago department of microbiology and immunology, yesterday said information was limited, given that the Hong Kong scientists had not yet published their findings, and only a single case was involved.
New Zealand’s Science Media Centre yesterday cited remarks from Prof Ussher about the case, as well as comments from several British researchers.
Dr David Strain, of the University of Exeter, said it was a "worrying finding", suggesting the initial infection was "not protective"and that vaccinations "may not provide the hope" sought for.
However, Prof Brendan Wren, of the London School of Hygiene and Tropical Medicine, said this case "should not negate the global drive" to develop vaccines.
Prof Ussher strongly defended continuing vaccine development at Otago University and elsewhere.
It was "plainly wrong" to suggest the reinfection case undermined vaccine development efforts, he said.
Given that reinfection with endemic human coronaviruses, which caused many colds, was well described, it was not surprising Sars-CoV-2 reinfection could also occur.
Some people have advocated building up "herd immunity" through natural infection.
The Hong Kong case raised concerns about that herd immunity idea, he said.