Chinanews.com, Beijing, December 12 (Shao Meng) The new coronavirus variant JN.20 is accelerating its spread around the world, and local cases have also appeared in China. The National Bureau of Disease Control and Prevention issued a document on the 1th, saying that as of December 15, a total of 12 cases of the JN.10 variant have been monitored in local cases in China. The news sent JN.7 to the spotlight on social media.

How is the JN.1 variant different from the previous coronavirus? How fast and pathogenic is it? What is the impact on the peak of respiratory infections that the country is experiencing? Will it trigger a new round of epidemic in our country?

In response to the above questions, Chinanews interviewed Lu Hongzhou, director of the National Clinical Research Center for Infectious Diseases and president of the Third People's Hospital of Shenzhen, and Jiang Qingwu, an epidemiologist and professor at the School of Public Health of Fudan University.

The JN.1 variant has been circulating in many countries

It cannot be ruled out that it may become the dominant epidemic strain in China

Lu Hongzhou told Chinanews that the JN.1 mutant strain is a subclade of the new coronavirus Omicron variant BA.2.86, and compared with BA.2.86, the receptor binding region (RBD region) of the JN.1 variant has an additional L455S mutation. Recent studies have found that the L1S mutation of the JN.455 mutant strain further enhances its immune evasion ability.

The results of global monitoring show that in November, the growth rate of BA.11.2, especially the JN.86 subclade, has accelerated significantly, and it has become one of the dominant epidemic strains in some countries. As of December 1, the JN.12 variant has been detected in at least 10 countries around the world. On December 40, the World Health Organization singled out the JN.1 variant as a "variant of concern". The JN.12 variant poses a low additional risk to global public health at the moment, but with the onset of winter in the northern hemisphere, it could increase the burden on public health systems in many countries to deal with respiratory infections, WHO said.

Chang Zhaorui, a researcher at the Infectious Disease Management Department of the Chinese Center for Disease Control and Prevention, introduced at a press conference of the National Health Commission on December 12 that the monitoring results of China's new coronavirus variants show that the current BA.17.2 variant accounts for a very low proportion of China's reported sequences, but the proportion of imported cases has increased rapidly since November, and the growth trend is gradually converging with the world.

Changing trends. Source: China Center for Disease Control and Prevention

The popular science article released by the National Bureau of Disease Control and Prevention also pointed out that although the current prevalence level of the JN.1 variant in China is extremely low, it is affected by the international epidemic strain and imported cases, and the possibility that the JN.1 variant will become the dominant epidemic strain in China cannot be ruled out.

Experts say there is still a need to be vigilant against a rebound of the new crown this winter

Does it worsen the wave of respiratory infections?

At present, China is in the season of high incidence of respiratory tract infectious diseases, what is the impact of the introduction of the JN.1 variant on the peak of respiratory infections that China is experiencing? Will it trigger a new wave of popularity?

In Jiang Qingwu's view, the prevention and control of influenza has been normalized, and the pathogenic mutation of influenza viruses cannot be stopped, and the incidence of influenza in this autumn and winter is more than in the previous three years. At present, the influenza infection situation in China has shown signs of alleviation, and the number of outpatient and emergency respiratory disease diagnosis and treatment and the number of hospitalizations in hospitals are declining. The Weekly Report on Influenza Surveillance for Week 49 (12 December-4 December) also showed a downward trend in the positivity rate of influenza virus tests in individual provinces during the week.

"My concern is that this wave is mainly the flu, and the coronavirus infection is at a low level of epidemic. However, according to the previous transmission pattern and epidemic characteristics of the new coronavirus, in late December and January, we need to be highly vigilant that the new coronavirus will affect us again. At present, there are countries where the spread of the new crown is far more active than ours. Jiang Qingwu said that it is recommended to actively prepare for the prevention and control of respiratory infectious diseases.

Data map. Photo by Zhang Yuhui

Lu Hongzhou said that although the immune evasion ability of JN.1 has increased, there is currently no evidence that JN.1 has increased pathogenicity. In addition, since December last year, the new coronavirus and other respiratory pathogens have been co-epidemic in China, and at present, Chinese residents have generally experienced two or even three infections. It has been shown that such an experience of infection can lead to a strong and broad-spectrum of neutralizing antibodies against different submutant strains of Omicron in infected individuals.

"The future epidemic of JN.1 in China may cause a small peak of infection, which will increase the medical burden of hospitals to a certain extent, but our existing experience and medical resources are sufficient to cope with this situation, so theoretically JN.1 will not have much impact on the peak of respiratory disease infections that China is experiencing." Lu Hongzhou speculated.

The risk of severe clinical infection is low

COVID-1 vaccines containing XBB.5.<> are still effective

According to the National Bureau of Disease Control and Prevention, studies have shown that there is no significant difference between the JN.1 and XBB variants in terms of transmission. The World Health Organization has assessed the risk of severe clinical infection of the BA.1.2 variant, including JN.86, as low. China's surveillance data show that the JN.1 variant infection is mild or asymptomatic.

In addition, the World Health Organization (WHO) reported that COVID-1 vaccines containing XBB.5.1 are still effective against the JN.<> variant.

Lu Hongzhou introduced that at present, China has approved a total of 5 new crown vaccines containing XBB mutant strain components, including recombinant protein vaccines, mRNA vaccines and recombinant adenovirus vector vaccines.

He said that although recent studies have found that the L1S mutation of the JN.455 mutant strain further enhances its immune evasion ability and has a certain escape ability to the humoral immunity induced by XBB.1.5 breakthrough infection, the existing data also show that vaccination can significantly increase the speed and intensity of antibody production and provide better protection for the body, so vaccination is still necessary.

An elderly man gets vaccinated against the coronavirus. Photo by Zhou Lishuo

Jiang Qingwu also pointed out that effective vaccination is an effective measure to control the spread of infectious diseases and protect the population, and influenza vaccination should be actively promoted, especially for children and the elderly. Regions and industries with conditions can promote free influenza vaccination.

In addition, some crowd control measures that have been effective in the past should be actively promoted, such as washing hands after returning from going out; During the epidemic season, wear masks in indoor public places and public transportation; medical and public health departments have strengthened prevention, control and surveillance; The health supervision department should do a good job in the management of fever clinics, and analyze and publish the incidence information in a timely manner.

"Although the pathogenicity of the new crown is decreasing, it is still necessary to attach great importance to the protection of the elderly and recommend the most effective vaccines to the elderly population. The season for the spread of respiratory infections has arrived, and medical and public health departments need to prepare technically and materially. Jiang Qingwu said. (ENDS)