A new variant of Covid that is a hybrid of the infectious Indian and British strains has been identified in Asia.
Vietnam’s health minister said it appeared to be more infectious than other types circulating in the country.
The British and Indian variants are highly infectious but have not yet shown the ability to evade vaccines, one of the biggest fears of scientists battling the pandemic.
“We have discovered a new hybrid variant from the Indian and the UK strains,” Health Minister Nguyen Thanh Long said.
“The characteristic of this strain is that it spreads quickly in the air. The concentration of virus in the throat fluid increases rapidly and spreads very strongly to the surrounding environment.”
Most of the new transmission was found to have occurred in Bac Ninh and Bac Giang, provinces with densely populated industrial zones in which hundreds of thousands of people work for major companies including Samsung and Canon.
In the country’s largest metropolis, Ho Chi Minh City, home to nine million people, at least 85 people have tested positive as part of a cluster at a church, the Health Ministry said.
Worshippers sang and chanted while sitting close together without wearing proper masks or taking other precautions.
Vietnam has since ordered a nationwide ban on all religious events, and major cities have banned large gatherings, and closed public parks and non-essential businesses.
Cafes, restaurants and hair salons as well as tourism spots have been ordered to close.
The new variant could be responsible for a recent surge in cases of the coronavirus, which has spread to 30 of the country’s 63 municipalities and provinces, Mr Nguyen said.
Vietnam was previously seen as a success story in battling the virus.
On May 1, its caseload since the start of the pandemic was 2,942, with 35 deaths. But in the past few weeks, the country has confirmed more than 3,500 new cases and 12 more deaths.
Vietnam, with 97 million people, has vaccinated about a million citizens.
It is now speeding up its programme and hopes to achieve herd immunity by the end of the year, Mr Nguyen said.