In an urgent document issued on April 18 by Hanoi vice chairman Vo Thu Ha, people are requested to wear face masks when using public transport or visiting public places including bars and dance clubs.

The move came after Hanoi witnessed a surge in the number of Covid-19 infections since early April. The city has also detected patients infected with the new Covid-19 XBB.1.9.1 sub-variant which is rapidly transmissible with a mild clinical course and is classified by the World Health Organisation as a variant under monitoring.

Hanoi currently has 566 Covid-19 cases being treated, including two severe cases requiring mechanical ventilation. There are nearly 100 new infections reported daily. The director of the Department of Preventive Medicine, Phan Trong Lan, said that the number of new cases may rise.

He stressed the need to protect vulnerable groups such as the elderly, people suffering from underlying diseases, and pregnant women.

The capital has allocated a total of 17,800 doses of the AstraZeneca vaccine to its districts to be given as booster shots for people aged over 18.

Vietnam has witnessed a reoccurrence of Covid-19 cases over the past week. The country confirmed 1,522 new infections on Tuesday, up 491 cases from the previous day's figure. According to experts, the actual figure may be higher as many people undergo a self-test and self-treatment at home.

The Ministry of Health has asked localities nationwide to tighten preventive measures to curb the spreading of the virus, including speeding up vaccination.

Around 832,900 doses of the AstraZeneca Covid-19 vaccine have been allocated to localities across the country as booster shots for people aged 18, according to the National Institute of Hygiene and Epidemiology.