Medics collect samples of workers at Tan Thuan Export Processing Zone
in HCMC's District 7 on June 3, 2021. Photo by VnExpress/An Phuong. 

Large-scale coronavirus testing is being conducted among more than 320,000 workers across all export processing zones, industrial parks and high-tech zones in Ho Chi Minh City. 

Health authorities on Wednesday collected samples of more than 30,000 workers at 22 companies in Tan Thuan Export Processing Zone of District 7, one day after 45,000 workers at Saigon Hi-tech Park had their samples taken for testing, the HCMC Export Processing Zone and Industrial Park Authority (HEPZA) said Thursday.

Mass testing has been rolled out after the city in the past five days detected three Covid-19 cases at three industrial parks of Tan Binh in Tan Binh District, Tay Bac in Cu Chi District and Vinh Loc in Hoc Mon District aside from four other cases at a company in Quang Trung Software Park of District 12.

As industrial complexes usually gather a large number of workers in one place, the city deemed them Covid-19 threats.

The city is home to 17 export processing zones and industrial parks with 280,000 workers in total, and one hi-tech park with 45,000 workers. All will be tested, starting with factories having more than 500 employees.

More than 3,000 foreign experts working for 1,500 companies at these parks and zones will also be screened.

"HCMC has 1.6 million workers and without proper measures to control the pandemic, there could be a crisis," Minister of Health Nguyen Thanh Long warned city officials at a meeting Tuesday.

HCMC has recorded 277 Covid-19 cases so far in the fourth wave that broke out in Vietnam in late April.

Its recent cluster, which emerged last Wednesday at a Christian congregation based in Go Vap District, has been responsible for at least 248 cases in the city as of Thursday morning.