Yet another mutant coronavirus strain detected in Japan after four passengers from Brazil test COVID-19 positive

Amid concerns over the rising number of coronavirus disease (COVID-19) cases globally, on part due to the recently-detected mutant strains, yet another new coronavirus variant has been detected in Japan.

Japan's National Institute of Infectious Diseases (NIID) informed on Sunday (January 10) that the new strain of the coronavirus was detected after four passengers arriving from Brazil tested positive for COVID-19.

The passengers, while in airport quarantine, tested positive for COVID-19 and the new mutant strain was detected through a detailed examination by the NIID, according to the ministry.

Of the four people who arrived from Brazil, a man in his 40s showed no symptoms upon arrival, but later developed breathing difficulties and was hospitalised, Japan's health ministry said. Another woman, in her 30s, developed a headache, while a male in the 10-19 age group had a fever. The fourth passenger, a woman in the same age group, is asymptomatic, the ministry said.

In a statement, the NIID said that as of now, there is no available evidence to suggest that the new coronavirus strain is more infectious than the previously-detected variants, although its genetic makeup is similar to those found in the United Kingdom (UK) and South Africa.

Japan has already informed the World Health Organisation (WHO) of the new coronavirus variant detected from Brazil, and is currently investigating how infectious the strain is and whether or not it is resistant to vaccines.

It is also not yet known if the new variant causes more severe symptoms in victims.