The Health Ministry confirmed 52 new local Covid-19 cases Friday morning, bringing the number of infections in the ongoing wave to 5,008.
The new cases were recorded in the northern provinces of Bac Giang, Bac Ninh, Thai Binh and Hanoi.
In Bac Giang, 35 new Covid-19 patients are all related to clusters at industrial parks and have been isolated prior to testing.
Bac Ninh reported 14 cases, including six related to its Khac Niem industrial park, three linked to Que Vo industrial park, two associated with a cluster in its Thuan Thanh District. For the remaining three, health authorities are still looking into their source of transmission.
For the two cases in Hanoi, one is a 39-year-old man living at the Hemisco Xa La apartment building in Ha Dong District who got infected after a trip to HCMC. He visited the southern metropolis on May 26 and worked at a real estate company on Vo Van Kiet Street, District 1, which has recorded three infections linked to the city's religious mission cluster. He returned to Hanoi four days later and self-isolated himself at home before testing positive.
The other case is a person who has had contact with a Covid-19 patient.
The patient in Thai Binh is a woman who is related to a former cluster and has already been isolated.
Vietnam has been suffering the fourth wave of Covid-19 for 39 days. Infections have been recorded in 37 of its 63 cities and provinces.
Bac Giang and Bac Ninh continue to account for most cases, at 2,713 and 965, followed by Hanoi with 430, of whom more than 140 are in two hospitals under lockdown, and HCMC with 288.
Since the pandemic broke out last year, Vietnam has recorded 8,115 cases, which includ more than 3,000 recoveries and 49 deaths.