The Chinese city of Wuhan has instructed its officials to test its whole population of 11 million people for Covid-19 after six new infections emerged since lockdown measures were lifted on April 8.

New cases emerged from housing compound

According to the Hubei local government, the six locally transmitted cases, which were reported on May 10 and 11, emerged from a small residential complex in Wuhan.

The first patient was an 89-year-old man who quarantined himself since the end of the Chinese New Year, The Paper reported.

He first fell ill with feverish symptoms on March 17, but recovered in 10 days after taking some medication.

However, he started feeling ill again on April 15.

Accompanied by staff from the housing complex, he then went for testing on May 6.

By May 9, he had twice tested positive for Covid-19.

After Wuhan reported his case on May 10, five new cases were then reported on May 11.

Before this, no new cases have been reported since April 3.

The local party secretary was subsequently fired from his position after the new infections emerged.

Testing to be done within 10 days

Authorities announced on May 11 that the mass testing of the population would be completed within 10 days, calling the task a "10-day battle", Yicai reported.

Districts are supposed to come up with their own plans to execute the testings.

According to Caixin, about 1.03 million people in Wuhan have already been tested.

To complete the task within 10 days, more than 1 million tests would have to be conducted each day.

Peng Zhiyong, director of the intensive care unit at Wuhan University's Zhongnan Hospital, told Global Times that he has not received details of the testing plan.

In addition, he said testing on such a scale would be costly, and so the testing is likely to focus on key groups such as the close contacts of patients and their family members, the elderly, medical staff, and those with preexisting medical conditions.

Second wave of infections would be costly

Since recovering from the virus outbreak and gradually making a return to pre-Covid-19 activities, Wuhan has been cautious in preventing a second wave of infections.

The far northern province of Heilongjiang has reported new imported cases from Russia, which shares the same border.

The provincial capital of Harbin has also reported a new spate of infections, which authorities said were brought by a returning Chinese student from New York City.

New cases have also appeared in Shulan, a city near the Russian and North Korean borders.

Calls for probe into Covid-19 origin

Even as Wuhan attempts to return to normalcy, it remains in the global spotlight.

Several western governments have called for an investigation in China to determine the source of the Covid-19 virus.

In particular, the United States had pushed for a probe into the virology lab in Wuhan, fuelling the conspiracy theory that the pathogen had somehow escaped from the maximum-security lab.

The theory was vehemently denied by the lab itself, and was also rejected by virus experts from outside of China.

China has recently said it supports an examination by the World Health Organisation, but opposes any "presumption of guilt".

Top image via Xinhua