An upward revision in China's coronavirus death toll was "an attempt to leave no case undocumented," World Health Organization (WHO) epidemiologist Maria van Kerkhove told a briefing on Friday.

The city of Wuhan in central China revised its number of novel coronavirus disease (COVID-19) confirmed cases and deaths on Friday.

The total number of confirmed COVID-19 cases in Wuhan as of the end of Thursday was revised up by 325 to 50,333, and the number of fatalities up by 1,290 to 3,869.

Kerkhove said the Chinese authorities had gone back over data from funeral services, care homes, fever clinics, hospitals and detention centers, as well as the number of patients who had died at home, in Wuhan.