The northern port city of Hai Phong, around two hours to the east of Hanoi, requires those coming from certain places in Hanoi where cases were recorded to be quarantined for 21 days.

They are Tien Thang Ward in Me Linh District, Dich Vong in Cau Giay District, Uy No Commune in Dong Anh District, Xuan Phuong Ward in Nam Tu Liem District, Phu Dien Ward in Bac Tu Liem District, and Vinh Tuy Ward in Hai Ba Trung District.

People returning from other parts of Me Linh, Cau Giay and Nam Tu Liem Districts must quarantine themselves at home.

In Hanoi 21 people were diagnosed with the disease in the latest outbreak, all linked to neighboring Hai Duong and Quang Ninh provinces, the country's major hotspots.

Those coming from certain areas with recorded infections in Bac Ninh, Hoa Binh, Bac Giang, Gia Lai, and Binh Duong provinces, and HCMC will also be quarantined in Hai Phong for 21 days.

Thua Thien-Hue Province requires all visitors from Quang Ninh, Hai Duong and pandemic-hit areas in Hanoi to be quarantined for 21 days and tested using RT-PCR method.

Everyone coming from other localities need to make medical declarations.

Authorities have also ordered all personnel at Phu Bai International Airport and major ports and bus stations to be tested.

In Nghe An Province, around 300 km (190 miles) south of Hanoi, Nguyen Van Dinh, director of the local Center of Diseases Control, said all visitors from areas under lockdown and social distancing would be quarantined and tested.

Authorities in neighboring Ha Tinh also require people coming from pandemic-hit and locked-down places to be quarantined for 14 days.

Thanh Hoa Province, around 160 kilometers south of Hanoi, has mandated quarantine for people coming from places designated as pandemic-hit by the Ministry of Health.

Nam Dinh Province near Hanoi has also announced quarantine requirements for people from places with community transmission during the latest outbreak.

With a week to go before the Lunar New Year, people across the country are flocking home to reunite with their families and celebrate the country's biggest and most important festival.

There have been 366 cases reported within a week.

Many localities have also suspended Tet festivals, scaled down fireworks shows and banned large gatherings.