A man from Hong Kong who first contacted COVID-19 four and a half months back has again tested positive for the novel coronavirus, prompting experts to declare this is the first case of its kind in the world.
However, according to experts, a recurrent COVID-19 may not necessarily be as severe as it is in the case of the first infection. The WHO has warned not to jump into conclusions based on the data of a single patient, the BBC reported.
The man from Hong Kong, believed to be in his early 30s, tested positive for the virus after experts found two “clearly different” strains of virus following a genome sequencing.
The virus was detected at an airport terminal while routine checking. The man, who is an IT worker was returning from Europe earlier this month.
According to media reports, the man returned from Spain to Hong Kong in mid-August when he carried a different strain of the virus. In his first-time infection, he had mild symptoms, and the second time he had none.
“It shows that some people do not have lifelong immunity” to COVID-19 after the first infection, the University of Hong Kong microbiologist Dr. Kelvin Kai-Wang To said. “We don’t know how many people can get reinfected. There are probably more out there.”
Experts suggest a person with COVID-19 reinfection can still spread the virus to someone who has not been exposed to the virus, Corey Smith, head of translational and human immunology at the QIMR Berghofer Medical Research Institute in Brisbane told the AP.
So far, the novel coronavirus has infected more than 21 million people across the globe, killing hundreds of thousands, according to Johns Hopkins University COVID-19 data.
According to the University of Hong Kong press release, the finding is yet to be published in Clinical Infectious Diseases. Ideally, once a person is infected with COVID-19, the body builds up immunity against the virus that prevents reinfection.
However, in extremely rare case, one can contact the disease for the second time, just like the case of the Hong Kong man.