A 33-year-old man living in Hong Kong has been reinfected with Covid-19 for the second time this year, according to preliminary research.
He is the “first case” documented getting coronavirus twice.
He had symptoms the first time, but no obvious symptoms the second time, the team at the University of Hong Kong reported Monday.
The pre-print study – which the University of Hong Kong said has been accepted for publication in the journal Clinical Infectious Diseases – found that the man’s second case of Covid-19 occurred 142 days after the first.
During his first episode of illness, the patient had a cough, sore throat, fever and headache for three days, according to the study. He tested positive for Covid-19 on March 26.
Then during his second episode, the patient was returning to Hong Kong from travelling in Spain via the United Kingdom, and he tested positive during his entry screening at the Hong Kong airport on August 15, the researchers said. The man was hospitalized again but remained asymptomatic, CNN reports.
“The patient got re-infected 4.5 months after the first infection. Therefore, it shows that for this patient, the immunity induced by the first infection is short-lasting,” Dr Kelvin Kai-Wang To of the University of Hong Kong, who worked on the study, said in an email to CNN.