|Articles|August 24, 2020

First COVID-19 Reinfection Case Observed in Hong Kong

Investigators observed a second set of virus in a previously infected 33-year-old man, nearly 5 months after his first positive COVID-19 case.

The first confirmed reinfection case of coronavirus 2019 (COVID-19) has been reported in Hong Kong.

In a report from The New York Times Monday morning, investigators in China stated a 33-year-old man with mild COVID-19 symptoms during a prior infection is again confirmed to have the virus—only now in asymptomatic form.

The evidenced reinfection comes on the heels of US Centers for Disease Control and Prevention (CDC) guidance this month stating that persons who have tested positive for COVID-19 would not need quarantine nor testing for up to 3 months post-infection, so as long as symptoms do not redevelop.

The guidance was issued after published investigations varied on the conclusion that infected persons had approximate three-month COVID-19 immunity with developed antibodies.

The new reinfection patient, deemed “apparently young and healthy” by University of Hong Kong investigators in a statement, was first infected with COVID-19 more than 4 months ago.

His reinfection was reported following a trip to Spain, with a second set of virus being closely matched to a COVID-19 strain common in Europe during the last 2 months.

“Our results prove that his second infection is caused by a new virus that he acquired recently rather than prolonged viral shedding,” Kelvin Kai-Wang To, MD, a clinical microbiologist at the University of Hong Kong, said in the statement.


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