Tests carried out on a man suspected of being North Korea’s first officially acknowledged coronavirus case came back inconclusive, the World Health Organization has said.
The country has so far said it has had no COVID-19 infections, but there has been some scepticism over this claim.
Amnesty International interviewed two former North Korean healthcare professionals who had defected to South Korea who said the country’s health system was vulnerable to pandemics.
Some outside experts and US officials have also cast doubts on the claim, but no cases in North Korea have been independently confirmed.
Last week North Korea told foreigners not to leave capital city Pyongyang amid coronavirus fears.
The WHO said North Korea had quarantined over 3,635 primary and secondary contacts of the man suspected of having coronavirus.
On 26 July the country said it had declared a state of emergency and locked down the border city of Kaesong after a person who defected to South Korea three years ago returned across the fortified border with what state media said were symptoms of COVID-19.
At the time, state media was unclear if the man had been tested, saying “uncertain result was made from several medical check-ups”.
But leader Kim Jong Un declared that "the vicious virus could be said to have entered the country".
If confirmed, the case would have been the first officially acknowledged by North Korean authorities, but since then, state media have continued to say no cases have been reported.
"The person was tested for COVID-19, but test results were inconclusive," Dr. Edwin Salvador, WHO representative for North Korea, said on Wednesday.
Kaesong remains under lockdown, and household doctors continue to conduct surveillance in the city, he said.
Despite having no confirmed cases, North Korea had imposed a widespread lockdown and conducted contract tracing, Salvador added.
North Korea's ruling party newspaper Rodong Sinmun called on Wednesday for all citizens to take part in anti-epidemic measures, warning that any breach of rules could have "critical consequences".
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