Eighteen of the new cases are in the northern province of Hai Duong, now the epicenter of the outbreak.

Quang Ninh, which neighbors Hai Duong and is also a major Covid-19 cluster, has eight, the Central Highlands province of Gia Lai has three and Hanoi has one.

The patients in Gia Lai and Hanoi are related to previous cases confirmed in Hai Duong and Quang Ninh, where the first domestic transmissions of the new outbreak were detected on January 28.

While the source of transmissions of the ongoing outbreak is yet to be identified, it has been determined that it was caused by the U.K. variant, which has been described as more contagious and having a shorter incubation time.

The other case reported Tuesday evening is an imported one, a 43-year-old male Russian expert who landed in Hanoi Monday on AZUR Air flight ZF2074/2078.

Six days since Vietnam recorded the return of Covid-19 community transmissions after 55 clean days, the number of infections have jumped to 301, including 224 in Hai Duong and 38 in Quang Ninh. Infections have spread to eight other cities and provinces - Hanoi with 20 cases, Gia Lai with nine, Bac Ninh three, Hoa Binh two, Binh Duong two, and HCMC, Hai Phong and Bac Giang one each.

So far, the country has recorded a total of 1,882 Covid-119 cases of which 383 are active.