COVID-19 mutant strains found in India have been detected in some Chinese cities, Wu Zunyou, the chief epidemiologist of the Chinese Center for Disease Control, said on Thursday. Wu reminded the public that implementing epidemic control measures is key to curbing the spread of virus variants.

Zhoushan in Ningbo, East China's Zhejiang Province reported Thursday that 11 Chinese crew members on a cargo ship now docked in the city tested positive for COVID-19 recently. All were imported infections from India, according to authorities.

All the patients, 10 confirmed cases and one asymptomatic case, have been sent to a hospital for treatment, while nine other Chinese crew members remain on the ship for observation. A source close to the Zhoushan Health Commission told the Global Times that two patients are severely ill.

The ship, Huayang Chaoyang, is registered in China's Hong Kong Special Administrative Region. Since 2021, the cargo ship has docked at ports including Chittagong in Bangladesh, Kakinada in India, Singapore, and Xiamen in China. It is now docked at a shipyard in Zhoushan awaiting repairs.

The Global Times learned that Zhoushan, a coastal city famous for its Ningbo Zhoushan Port, is adopting strict epidemic control measures on vessels entering the port to prevent imported infections.

According to the current epidemic control policy at the port, ships that have passed through ports in India within three months are not allowed to enter the port, while those which have left Indian ports for more than three months will be allowed to enter with all their crew members returning negative nucleic acid tests, a staff from the Zhoushan Longshan Shipyard Company told the Global Times on Thursday.

The staff said that his company has received some ships that used to dock at ports in India and Southeast Asian countries.

A lot of ships coming to Zhoushan have stopped over in India, because India is a must-pass station for many ships coming from Europe to China, an insider from a container transport told the Global Times on Thursday.

Prior to cases in Zhoushan, Southwest China's Chongqing Municipality reported an imported case of COVID-19 on Wednesday, who had previously worked in India. As India is plagued by a new wave of COVID-19 infections and sees new variants spreading quickly, cases from India have raised public concerns that the variant could spread in China.

Wu noted that the virus has been mutating constantly since the epidemic, and that it is crucial to put epidemic control measures into practice, which will not only stop the mutated strains but also stop new mutations from coming out.

Wu said people should still keep alert in the face of increasing imported cases and epidemic control measures, as China has invested a lot to gain good results in epidemic control. The latest COVID-19 surge in India has sounded a stark warning that epidemic control is a complicated, difficult and long-term task, he said.