After nearly a month of the nation's fourth coronavirus wave, 1,340 community transmission cases have been recorded in 28 cities and provinces, the toughest Covid-19 wave Vietnam has ever had to face.

Long anticipated that the wave might "last longer, be on a larger scale with many outbreaks and more transmissible variants," adding that localities however should decide on appropriate social distancing measures to curb the disease, not applying them indiscriminately.

Among the new cases, 35 percent are workers in eight cities and provinces.

In the coming days, more coronavirus-positive cases should be expected as tests are being conducted at industrial areas with high risk of infection across the country, Long said.

Bac Giang Province has shut down four industrial parks, which host hundreds of companies and around 136,000 workers, to curb the spread of the disease.

Its neighbor Bac Ninh has said it would stop employing 30,000 workers from Bac Giang, saying the move was to "promptly detect and stop infections, while limiting the number of infected cases from entering the province's businesses."

So far, Bac Giang has recorded 411 local cases, making it the hardest hit locality in the ongoing Covid wave, with 80 percent of them being workers.

Authorities and medical workforce from other localities are also supporting Bac Giang with testing labs and medical workers to help with the province contact tracing and Covid-19 testing efforts.