Guangdong's latest cases linked to variant first found in India, UK

The local infections found in south China's Guangdong Province since May 21 have shown a high similarity with the highly contagious COVID-19 variant found in India and the UK according to their genome sequences, officials said on Sunday.

The capital city of Guangzhou has logged five new confirmed cases of COVID-19 and 21 asymptomatic infections since May 21. Thirteen asymptomatic cases have been found in Shenzhen during a recent resurgence of COVID-19 infections.

Chen Bin, vice director of the provincial health commission, said that all the locally transmitted cases found in Guangzhou are linked to the B.1.617 variant first found in India.

Shenzhen health commission said the infection chain in the city started from a worker handling international cargoes at the Yantian Port, and most of the patients are infected with the B.1.1.7 variant first found in the UK.

Most of the latest infections in Guangzhou are believed to be linked to a 75-year-old woman who was confirmed on May 21 to have the virus. Most of the others attended a dinner with her or live together.

The spread of infections in Guangzhou was "fast and strong," said Jiang Qingwu, a professor at Fudan University's School of Public Health.

Guangzhou, a business and industrial center of 15 million people, on Sunday required people leaving the city to have a negative result of nucleic acid test done within three days.

Guangzhou has expanded COVID-19 screening regions, from Liwan District to Yuexiu District and Haizhu District, as well as key areas in the districts of Tianhe, Baiyun and Panyu, according to local health authorities.

A notice by the Guangzhou health bureau issued on Saturday identified five streets in Liwan district in the city center as "high-risk areas" and ordered residents to stay indoors until door-to-door testing is completed.

Outdoor markets, child care centers and entertainment venues were closed. Indoor restaurant dining was prohibited. Grade schools were told to stop in-person classes.

People in parts of four nearby districts were ordered to limit outdoor activity.

The city government earlier ordered testing of hundreds of thousands of residents following the initial infections. The government said some 2.25 million people had been tested by Saturday. China reports a handful of new cases every day but almost all are people who were infected abroad. 

The Chinese mainland on Saturday reported 11 new cases, all of which were imported, the National Health Commission said in its daily report on Sunday.