North Korean COVID-19 testing numbers have fallen back to Earth after soaring to unprecedented highs last month, the latest data from the World Health Organization (WHO) shows, even as it remains unclear what drove the weekslong surge in testing.

The DPRK tested 3,991 samples between March 11 and 17, a more than fourfold decline from 16,287 samples between March 4 and 11, according to the WHO’s weekly situation report published late Sunday. 

The number of people screened for COVID-19, on the other hand, was consistent with weekly totals since early February. North Korea reported that it tested 1,282 people from