Omicron mostly asymptomatic, less lung damage likely: minister

Son said the number of Omicron Covid-19 cases in Vietnam is too small for the health sector to draw any specific conclusions on the new strain.

For now, there is very little data to compare it with the Delta variant, but all Omicron cases isolated and treated in Vietnam are asymptomatic, and this could be because this strain causes less damage to the lungs, affecting the upper respiratory tract, mainly, he told VnExpress Tuesday.

Vietnam has found 25 people with Omicron so far, all arriving from abroad. No locally transmitted case has been detected.

Of these, the five cases confirmed in HCMC on January 1 all had a low virus concentration. They stayed asymptomatic and tested negative after five-seven days. Some relatives living with the patients have not got infected.

The first case of Omicron infection in Vietnam, a person arriving in Hanoi from the U.K., was discharged from hospital last Sunday after two weeks of treatment, during which he did not show any symptoms.

Several studies published in December by different universities have found Omicron to be less severe on the lungs than previous variants of the novel coronavirus.

A study conducted on animal and human tissue published on December 31 by the Berlin Institute of Health said Omicron produced less-damaging infections, often limited largely to the upper airway: the nose, throat and windpipe, and the variant did much less harm to the lungs, whereas previous variants would often cause scarring and serious breathing difficulties.

The U.K. Health Security Agency announced on Jan. 1 that it had analyzed more than a million Covid-19 cases and found the risk of hospitalization from Omicron was three times lower than that of the Delta variant.

Commenting on the rate of spread and the risk of community infection caused by the Omicron strain in Vietnam, Deputy Minister Son said that all Omicron infections so far have been detected in isolation areas and were under control.

"We can also be more secure now that we have the Covid-19 vaccine," he said.

Vietnam has already allowed administration of the third vaccine shot to adults three months after their second shot.

The Ministry of Health had said in December that the risk of Omicron penetrating and then spreading in Vietnam is "very high."

It had required authorities in cities and provinces to strengthen pandemic prevention and control measures including tightened inspection of foreign arrivals.

All samples suspected to be infected with the new variant must be sent to the National Institute of Hygiene and Epidemiology and Ho Chi Minh City Pasteur Institute for gene sequencing, the ministry said.

Health experts had also said that Vietnam should beef up its healthcare system, ensuring that medical centers are well-equipped and can up their capacity, so as to avoid an Omicron-triggered overload because this variant was said to be more contagious than previous strains, including the Delta variant.

Tran Dac Phu, a senior advisor with the Public Health Emergency Operations Center, said too many cases could lead to a situation in which severely ill patients are unable to access proper treatment in time, leading in turn to a high fatality rate.

After it was first detected in South Africa late November, the Omicron variant had been identified in 110 countries and territories as of Dec. 22.