BEIJING -- China reported a slight increase in new coronavirus cases for the second straight day, as the number of infections involving incoming overseas travellers hit a two-week high.

China reported 63 new cases on Wednesday, up from 62 a day earlier, the National Health Commission said.

Of those, 61 involved travellers arriving from overseas, the health authority said on Thursday, the most since March 25.

That brings the total number of confirmed cases in mainland China to 81,865.

While infections have fallen from their peak in February after China locked down several cities and imposed strict travel restrictions, authorities have called for continued vigilance amid fears of a second wave of infections.

The virus, which first broke out in the Chinese city of Wuhan in late 2019, has since spread around the world infecting more than 1.4 million people, killing more than 82,000.

The pandemic has wreaked havoc on the global economy as governments imposed lockdowns to rein in its spread.

China’s main concern now is managing infected travellers arriving from abroad and asymptomatic people, or virus carriers who exhibit no clinical symptoms such as a fever or a cough.

The total number of imported cases have reached 1,103 as of Wednesday, comprising mostly returning Chinese students.

New asymptomatic cases slipped to 56 from a record 137 a day earlier, with overseas arrivals accounting for half of the new cases. Of the new infections involving asymptomatic carriers, the central province of Hubei accounted for 24 cases.

Restrictions on outbound movement of people from Wuhan, capital of Hubei and epicentre of the outbreak in China, were lifted on Wednesday after a virtual lockdown of over two months.

While Wuhan has only reported three confirmed cases in the past three weeks, the megacity of 11 million people in the middle reaches of the Yangtze river still sees daily new cases of asymptomatic carriers.

People with no symptoms, which China does not include in its tally of confirmed cases until they exhibit clinical signs of infection, are still infectious and carry risk of transmission, Chinese authorities warn.

As of Wednesday, 3,335 people in China have died from the virus that causes a flu-like disease. Wuhan accounts for more than 75% of the fatalities.