Japan confirms first case of new COVID-19 strain that slipped through net

The health ministry Sunday reported the eighth case of infection with a coronavirus variant found in Japan — the first known case of the variant having passed through airport screening undetected.

The variant, similar to the one spreading in Britain, was found in a Tokyo resident in her 50s who recently returned from the country.

She arrived at Tokyo International Airport at Haneda on Dec. 13 after staying in Britain. She was judged negative for the novel coronavirus through airport quarantine screening.

But she turned out positive after developing a mild fever and a sore throat and visiting a medical institution Dec. 19. She was admitted to hospital Tuesday.

She was under self-quarantine at an accommodation facility from the day of her return to Japan until the hospitalization. She did not use public transportation or have close contact with anybody.

“If infections with highly infectious variants increase, the number of severely ill patients will also increase,” said Takaji Wakita, director-general of the National Institute of Infectious Diseases.

“We’re developing a quick diagnosis method for such variants, but it is also necessary to prevent them from entering (Japan) as much as possible,” Wakita told a news conference.

In airport screening, quantitative antigen tests are conducted. This method tends to show negative results for carriers who caught the virus very recently, according to Wakita.

“That is why we’re asking for two-week self-quarantine after return from abroad,” he said. “This time, the system worked.”

On Friday, the ministry reported the country’s first coronavirus variant infection cases, saying that five people who returned from Britain were found infected with the variant through airport screening.

The ministry Saturday said the variant was detected in a pilot exempted from such screening who recently visited Britain and a member of his family with no history of visiting the country.

Ministry officials said the variant is unlikely to spread in Japan anytime soon because all close contacts linked to the confirmed variant cases have been identified and placed under self-quarantine. (Japan Times)