The northern hemisphere may see a flu peak this winter, and experts call for attention to the risks of flu and COVID-19

At the "World Influenza Day" science popularization and academic conference, many academicians and experts reminded the public to strengthen prevention and control, and called on industry insiders to strengthen scientific research on influenza prevention and control during the COVID-19 epidemic.

Written by reporter Zhao Tianyu New Media Editor: Lv Bingxin

"With the relaxation of public health prevention and control measures, there is a risk of a global superposition of the COVID-19 epidemic and influenza epidemic this winter." November 1 is the fifth World Flu Day. At the "World Flu Day" science popularization and academic conference (hereinafter referred to as the conference) held on the same day, many academicians and experts reminded the public to strengthen prevention and control, and called on industry insiders to strengthen scientific research on influenza prevention and control during the COVID-19 epidemic.

The World Health Organization has estimated that seasonal influenza epidemics can cause 3 million to 5 million severe cases and 290,000 to 650,000 deaths worldwide each year. Pregnant women, infants, the elderly and patients with chronic underlying diseases are all high-risk groups.

Due to the implementation of COVID-19 prevention and control measures, global influenza activity has been generally at a low level in the past two years, but as countries around the world gradually relax control measures, a new peak influenza season may come.

Zhang Wenqing, head of the World Health Organization's Global Influenza Program, introduced that since the second half of 2021, monitoring has shown that the activity of influenza viruses has increased, whether in the northern or southern hemisphere, especially in the southern hemisphere winter of 2022 (this year's northern hemisphere summer), the activity of influenza viruses is even higher than before the outbreak of the new crown pneumonia epidemic. This may indicate that there will be a seasonal peak of influenza in the northern hemisphere this winter.

▲H5N1 influenza virus under an electron microscope

Gao Fu, an academician of the Chinese Academy of Sciences, believes that new subtypes of influenza viruses may emerge. In the past three years, the world has adopted relatively strict health and epidemic prevention measures, and the public's immunity to influenza is generally weak. At the same time, compared with the high vaccination rate of the new crown vaccine, the vaccination rate of influenza vaccine is still at a relatively low level. These are all factors worthy of attention.

According to the differences in influenza virus antigenicity and genetic characteristics, influenza viruses can be divided into four types: A, B, C and D, also known as types A, B, C and D. The influenza A virus, which is the most difficult for humans to deal with, can be divided into multiple subtypes based on the differences in HA and NA antigenicity. When influenza viruses of different subtypes meet, they will exchange genes and mutate into new hybrid viruses. Theoretically, there are 198 subtypes or even more.

How to effectively respond to the possible superposition of influenza and the new coronavirus? Zhong Nanshan, an academician of the Chinese Academy of Engineering, believes that once an epidemic caused by a respiratory virus breaks out, it will often lead to serious public health events, and thus become the focus of global infectious disease prevention and control. The COVID-19 epidemic has promoted basic research on the pathogenesis, accelerated the development of rapid clinical diagnostic methods, and provided an important basis for clinical epidemic prevention and control practices and disease prognosis judgment.

Gao Fu said that the development of COVID-19 vaccines, especially the development of MRNA vaccines, has provided a new idea for influenza vaccine development, and some concepts can be borrowed from each other. Dong Chen, an academician of the Chinese Academy of Sciences, believes that taking COVID-19 as an opportunity, my country has achieved a series of landmark results in respiratory virus research, and has formed a good technical reserve in clinical treatment, vaccines, drugs and antibodies, which can provide guidance for influenza prevention and control strategies.

Experts from Australia, the United Kingdom, Russia and other countries shared their views and understandings on influenza prevention and control at the exchange meeting, and believed that the development, application and promotion of COVID-19 vaccines provided inspiration for the development of universal influenza vaccines. In the prevention and control of influenza viruses, clear scientific prevention and control and basic research goals should be set, and the accessibility of influenza vaccines should be improved to promote the research of universal influenza vaccines.

It is understood that the theme of this conference is "Control and Response, Inclusion and Resilience" and it is jointly organized by the Chinese Society for Bioengineering, Chinese Center for Disease Control and Prevention, Institute of Microbiology, Chinese Academy of Sciences, Chinese Medical Association and Chinese Preventive Medicine Association. Disease control experts from many countries around the world were invited to attend, and six sub-venues were set up in Henan, Shandong, Sichuan, Guangdong, Hunan and Hubei.

Liu Jun, the person in charge of the conference and a researcher at the Institute of Viral Disease Prevention and Control of the Chinese Center for Disease Control and Prevention and deputy director of the National Influenza Center, expressed the hope that this conference will better promote cooperation and exchanges among global experts and scholars in the field of influenza and COVID-19 prevention and control, and contribute wisdom and strength to the fight against infectious diseases. "Only by building a double line of defense for prevention and control and development with resilience can the international community finally defeat the epidemic."