The central province of Hunan, which had recently downgraded its emergency response to the lowest level, reported its first imported infection on Wednesday, state media reported on Thursday, citing the provincial health commission.
Mi stressed further tightening epidemic control in communities around the country and conducting thorough epidemiological investigations to contain the virus.
As of Tuesday, a total of 81,554 confirmed cases of the COVID-19 had been reported on the Chinese mainland.
More than 44,100 people have died of the virus globally, with 883,200 cases reported, according to data compiled by the USA -based Johns Hopkins University.
Another 130 asymptomatic cases were reported, with a total of 1,367 such cases under observation as of March 31.
By Wednesday, 765 confirmed cases including four deaths had been reported in the Hong Kong Special Administrative Region (SAR), 41 confirmed cases in the Macau SAR, and 329 in Taiwan including five deaths.
"The Commission has always attached great importance to asymptomatic infections and taken strict measures to cope with such cases and their close contacts", he said.
Health officials also reported the first imported case from overseas in Wuhan - the epicentre where the virus first emerged late a year ago - heightening fears of infections being brought into China from other countries.
The first imported case confirmed in Wuhan on Wednesday was a Chinese national studying in Britain, who arrived in the city last week as it started to gradually lift travel restrictions imposed to control the outbreak.
"With effect from April 1, we will include reports of asymptomatic cases, any status change and how they are being handled, as part of our daily outbreak updates to address public concern", Chang said.
Luo explained that all infectious diseases have symptomatic and asymptomatic victims, with proportions varied.
Some experts believe that without coughing or sneezing, asymptomatic infections may be less infectious, it said.
China's health agency said it would begin including coronavirus patients without symptoms in its official tally, implicitly acknowledging that it has not been fully reporting data on the pandemic, according to reports.
Last week, World Health Organization epidemiologist Maria van Kerkhove said symptomatic patients were the main drivers of transmission, while most of those classified as asymptomatic developed symptoms a few days after diagnosis.