Fifteen of the cases were detected in Da Nang city, a coronavirus hotspot in central Vietnam. Most of them had come into close contact with confirmed coronavirus patients at Da Nang hospital.
The remaining six cases were in Quang Nam province and they were closely linked to the Da Nang hotspot. Three of them had visited patients at Da Nang hospital, while the other three had either taken care of a COVID-19 patient, or been given treatment at the hospital.
All new patients were aged between 20 and 83, according to the Ministry of Health.
Vietnam has been faced with the second wave of the coronavirus since the first case of community transmission was detected in Da Nang on July 25. The virus has since spread to nine cities and provinces nationwide, with Da Nang topping the list registering 135 cases.
It was followed by Quang Nam province (41), Ho Chi Minh City (8), Dak Lak and Quang Ngai provinces (3 each), Hanoi (2), and Thai Binh, Ha Nam and Dak Lak provinces (one each).
Meanwhile, Acting Minister of Health Nguyen Thanh Long warned the number of positive cases would keep rising as up to 40% of the newly registered COVID-19 patients closely linked to Da Nang hotspot do not show symptoms, but they still carry the pathogen and can spread the virus to others. He, therefore, requested medical workers not to overlook any suspected cases of nCoV infection.
As of 18.00hrs August 3, Vietnam has confirmed 642 coronavirus cases, of which 374 cases have fully recovered and six have died.