Outside Hubei Province, the epicenter, China's new confirmed cases of COVID-19 has been dropping for eight consecutive days, the NHC said.
More than 44,000 confirmed cases of the new virus have been reported worldwide, including 393 outside of China, in two dozen countries.
Hubei's health commission said it started including cases diagnosed with a new method.
The new diagnostic procedure could explain the spike in the death toll, according to Raina McIntyre, head of biosecurity research at the Kirby Institute at the University of New South Wales in Sydney.
There have been 1,367 deaths-with 1,310 of them in Hubei province.
Total cases of the new coronavirus in China have now hit 44,653, according to Chinese health officials, including 2,015 new confirmed cases on February 11. Non-sanctioned reporting on the outbreak by actitivists is challenging the Communist Party's tightly policed monopoly on information on an unprecedented scale.
Asian stock markets wobbled and the safe-havens of the Japanese yen, gold and bonds rose after the new Hubei numbers dashed hopes the epidemic was stabilizing and the Chinese economy could bounce back quickly.
Analysts said Hubei's new methodology to count infections might be for medical reasons and could be because Xi wants officials to be more transparent, but the immediate impact was to sow more distrust.
Temporary coronavirus hospital in converted Wuhan Sports Center
In Vietnam, official media reported that a commune of 10,000 residents northwest of the capital Hanoi was put in lockdown due to a cluster of cases there.
United States planemaker Boeing warned that there was "no question" the outbreak would hammer the aviation industry and the broader economy.
Most of the cases have been in Hubei, where about 56 million people have been placed under virtual quarantine.
In Japan, 39 new cases were confirmed on a cruise ship under quarantine at Yokohama, bringing the total to 174 on the ship.
Planemaker Boeing said airlines were facing a fall in profits as the crisis reduces passenger demand and prolongs weakness in economically sensitive air freight.
The ship has been turned away by the Philippines, Taiwan, Japan and Thailand, though its operator said no cases of the disease have been confirmed among the more than 2,200 passengers and crew.
U.S. Ambassador W. Patrick Murphy said the embassy will work with the ship's representatives and Cambodian officials to help Americans reach their destinations.
"This is an example of global solidarity we have been consistently calling for", World Health Organization chief Tedros said.