A staff member works at the health and quarantine comprehensive laboratory of Sichuan International Travel Health Care Center (Chengdu Customs Port Outpatient Department), in Chengdu, southwest China's Sichuan. Photo:Xinhua

Chinese mainland has detected seven cases of contracting COVID-19 subvariant JN.1 in about one month. The possibility of the variant becoming a dominant strain in the country cannot be ruled out, according to the National Disease Control and Prevention Administration.

Experts suggested the public not to overact about the new variant as infectious diseases are inevitable for all mankind but warned health threats posed by overlapping of various pathogens, including the dominant influenza and mycoplasma pneumonia with COVID-19.

Outside of China, since November this year, the proportion of JN.1 variant as a share of circulating strains has increased rapidly, from about 4 percent in early November to about 30 percent in early December. As of December 10, the variant has been detected in at least 40 countries worldwide.

The proportion of JN.1 variant in Europe was the highest, and its proportion in the US and other continents also showed a rapid growth trend.

On the Chinese mainland, the main strains at this stage are still EG.5 and its subvariants. Since the local JN.1 variant was first discovered in November, as of December 10, a total of seven JN.1 variants have been detected in the country.

"Although the current prevalence level of the JN.1 variant in China is extremely low, due to the subsequent impact of international epidemic strains and imported cases, the possibility of the JN.1 variant becoming a dominant epidemic strain in the country cannot be ruled out," the administration noted.

A Beijing-based immunologist who preferred not to be named told the Global Times more cases of JN.1 variant are expected as virus has no boundary and infectious diseases are the common destiny of all mankind. But it is not a concern of the public because new variants of the novel coronavirus can appear in the future anytime.

Only by improving immunity system can the public manage various pathogens infection and improve overall resistance to respiratory infections, the immunologist said.

Lu Hongzhou, head of the Third People's Hospital of Shenzhen, pointed out that although the immune escape ability of JN.1 had increased, there was no evidence to show that the pathogenicity of JN.1 variant had increased. According to the ministry, the seven JN.1 infections are mild and asymptomatic cases.

Some Chinese experts said people who have had the flu are more susceptible to contracting COVID-19. After being infected with the flu, it takes several months for CD4+ T cells in the body to recover. During the recovery process, the body's immune system is weaker, making it more susceptible to infection with the COVID-19.

According to latest weekly report by China CDC, the positive rate of influenza virus in southern and northern provinces of China slowed down between December 4 and 10, and some provinces showed a downward trend. The subtype A(H3N2) was predominant, followed by B(Victoria).