The World Health Organization was informed by North Korea that it has tested 25,986 people for the coronavirus through April but still has yet to find a single infection.

The WHO informed in a weekly examined report that North Korea’s testing figures include 751 people who were tested during April 23-29, of which 139 had influenza-like illnesses or severe respiratory infections.

The authorities have expressed cynicism about North Korea’s claim of a perfect record in keeping out Covid-19, given its poor health infrastructure and a penetrable border it shares with China.

North Korea has reported its anti-virus efforts as a “matter of national existence.” It has barred tourists, flown out diplomats and severely restricted cross-border traffic and trade.

The country has stopped issuing the number of people it quarantines this year, but formerly said it had quarantined tens of thousands who had exhibited symptoms.