JAPAN TIMES



 

People infected with the omicron variant of the novel coronavirus may have a tendency to show mild or no symptoms, although the variant’s infectiousness could be stronger than that of the delta variant, according to experts.

Experts are rushing to analyze the omicron variant after many reports that people fully vaccinated against COVID-19 were infected with the variant.
The omicron variant, first reported in South Africa, is rapidly spreading throughout the world. The new variant is quickly replacing the delta variant as the main cause of cases in South Africa, suggesting its strong infectiousness.

The risk of people developing severe symptoms after being infected with the omicron variant is unknown, but some data show that patients tend to have mild symptoms.

According to the European Union’s European Center for Disease Prevention and Control, 109 cases of infection with the omicron variant had been found in 16 countries as of Friday, and all of the infected people showed mild or no symptoms, with no reports of death.

The two people who tested positive for the omicron variant in checks at Narita International Airport in Chiba Prefecture were also reported to have mild symptoms, although they have fevers, according to the health ministry.

Takaji Wakita, head of the National Institute of Infectious Diseases, warns against making a hasty judgment regarding the risk of people infected with the omicron variant developing severe symptoms.

However, another expert said that if the risk of becoming seriously ill after infection with the omicron variant is the same as that for the delta and other variants, people may not have to take additional countermeasures other than regular precautions of wearing face masks and avoiding closed, crowded and close-contact settings, even if community infections with the new variant occur.

Breakthrough infection is another characteristic of the omicron variant.
The omicron variant has some 30 mutations in the spike protein, which allows the virus to enter human cells, far more than around 10 for the delta variant, according to the NIID. Due to the large number of mutations, vaccinations and antibodies that have been developed in past infections may become ineffective against the new variant.

In fact, the two people found to be infected with the omicron variant in Japan had received two doses of the coronavirus vaccine, including U.S. drug giant Pfizer Inc.’s.

“Breakthrough infections can occur with the delta variant. We need to examine the situation a little further in order to figure out if vaccines are less effective” against the omicron variant, compared with the delta variant, Wakita said.