South Korea and China have both offered support and medical supplies to the north, on humanitarian grounds. North Korea likely does not have enough testing supplies and state media reported the cause of the fevers was unclear.
Up until now, North Korea has managed to keep the virus out by implementing a strict quarantine policy and travel restrictions at early news of the outbreak in China, with which it shares a border – in January 2020. It has never previously formally reported a case of Covid-19, although health experts have said they believe the virus has been circulating there since March 2020.
Experts have warned a Covid outbreak could be devastating in a country with a broken health care system and an unvaccinated, malnourished population.
Some experts say the North's admissions of an outbreak suggested a willingness to receive outside aid.
It previously shunned vaccines offered by the UN-backed Covax programme, possibly because they have monitoring requirements.
State media said yesterday that a sub-variant of the highly transmissible BA.2 Omicron variant had been detected in Pyongyang, but did not provide case numbers or possible sources of infection.
Areas of the capital, Pyongyang, have reportedly been in lockdown for three days, with some people panic buying amid fears of shortages.
"There has been the biggest emergency incident in the country, with a hole in our emergency quarantine front, that has been kept safely over the past two years and three months since February 2020," the official KCNA news agency said.
Any previous suggestions of outbreaks in North Korea – such as reports that 180 soldiers could have died from the virus in early 2020, have been dismissed amid fears that it could damage the Supreme Leader Kim Jong-un, who was yesterday seen wearing a surgical mask for the first time in the outbreak.
The Workers' party politburo, held an emergency meeting amid news of the outbreak, where officials said they would implement "maximum" emergency measures. They reportedly include tighter border controls and lockdown measures, with Kim telling citizens "to completely block the spread of the malicious virus by thoroughly blocking their areas in all cities and counties across the country".
Overland trade between North Korea and China was suspended in late April because of a sharp increase in Covid cases in the Chinese border provinces of Liaoning and Jilin.
Cheong Seong-Chang, an analyst at South Korea's Sejong Institute, said the pace of the fever's spread suggests the crisis could last months and possibly into 2023, causing major disruption in the poorly equipped country.
South Korea's Unification Ministry, which handles inter-Korean affairs, said Seoul was willing to provide medical assistance and other help to North Korea based on humanitarian considerations.
The ministry's spokesperson Boo Seung-chan said Seoul does not immediately have an estimate on the number of vaccine doses it could share to North Korea if Pyongyang requests help.
Chinese Foreign Ministry spokesperson Zhao Lijian said on Thursday that Beijing was offering North Korea help in dealing with the outbreak.