HONG KONG — The news was abrupt and, to some, surprising: Overnight, a Chinese province near Russia, had cut its count of confirmed coronavirus cases by more than a dozen.

The revision stemmed from what appeared to be a bureaucratic decision, buried in a series of dense documents from the national government. Health officials said that they would reclassify patients who had tested positive for the new coronavirus but did not have symptoms, and take them out of the total count of confirmed cases.

The documents offered little detail or explanation, and skepticism was immediate. A Hong Kong newspaper called the decision a “disguise.” World Health Organization officials seemed caught off guard when asked about the move at a news conference this week.