Will influenza vaccine be difficult to get under the epidemic situation?

September 9 news into the autumn, with the temperature drop, autumn and winter influenza vaccination was put on the agenda by many people. In the novel coronavirus pneumonia epidemic situation, this year's vaccination demand is higher than before. Is "one needle hard to find" phenomenon? Influenza vaccine has been launched in many places.

The high incidence season of influenza is from November to march of the next year. Since it usually takes 2 to 4 weeks to produce antibody with protective level in human body after vaccination, September to October every year is the best time for influenza vaccination. The reporter combed and found that at present, influenza vaccine has been launched in many provinces in China. For example, the 60000 influenza vaccines scheduled for the first round in Gansu Province have been vaccinated by the end of August. On September 1, the first dose of live attenuated influenza vaccine made in China was also vaccinated in Shandong Province. In addition, Beijing also launched the bidding for influenza vaccine procurement in 2020-2021 in August.

From the perspective of local policies, many cities have also given preferential treatment to some special groups this year. According to a recent notice issued by Hangzhou CDC, it is clear that elderly people over 70 years old in Hangzhou can be vaccinated with influenza vaccine free of charge. Xiangyang City also announced that from September to October, all kinds of school students and kindergarten children in the city will be given free influenza vaccination, and special work will be completed before the end of October for children and students to check vaccination certificates, supplement certificates and re inoculation.

Why is influenza vaccination so important this year? The novel coronavirus pneumonia epidemic is spreading all over the world, which also makes influenza prevention and control in autumn and winter extremely attractive. According to who monitoring this year, three of the four most prevalent strains of influenza virus in the northern hemisphere have changed. Novel coronavirus pneumonia and flu symptoms were hard to be differentiated from WHO in August this year. In China, Wang Chen, an academician of the Chinese Academy of engineering and an expert in respiratory and critical care medicine, suggested that the most effective way to prevent influenza is to vaccinate influenza vaccine in a timely manner and to expand the vaccination population. In view of the situation of influenza prevention and control in autumn and winter this year, vaccine expert Tao Lina said in an interview with zhongxin.com that "the change of influenza virus strains at present belongs to prediction, which does not necessarily mean that these strains will be popular.

At present, although the virus strains change every year, they are generally relatively small changes. If a large mutation is predicted, they will be ready for battle 。” The novel coronavirus pneumonia emphasized that the vaccination of influenza vaccine is important in this autumn and winter. The main factors are the dual factors: first, from the perspective of epidemic control, if the patient has a fever after inoculating influenza vaccine, he can take the factors of influenza less into consideration and reduce the interference of the epidemic. Two, there is evidence that if there is a double infection of the new crown pneumonia and influenza, The symptoms will worsen. He said that compared with other types of vaccines, the protection rate of influenza vaccine is relatively low, and the current protection rate of influenza vaccine is generally between 60% and 70%, which means that if you want to form group protection, you need to have a high vaccination rate. Is there enough influenza vaccine to meet the increasing demand for vaccination? Statistics show that in the past, the domestic influenza vaccination rate was about 2% per year, far less than that of some western countries. However, affected by the epidemic this year, people's willingness to vaccinate has increased significantly.

"Last year, only the children in the family were vaccinated against influenza, but this year I want the whole family to be vaccinated as much as possible. I hope this can reduce the risk of running to the hospital." In an interview with reporters, Ms. Chen, a Beijing resident, said that she has been paying close attention to the time of influenza vaccination in Beijing recently, and hopes to make an appointment as soon as possible. Novel coronavirus pneumonia epidemic is the main reason for Zhang Xiaoshu's vaccination program, according to the director of the Gansu Provincial Center for Disease Control and immunization, who had previously said that the peak of vaccination in Gansu arrived earlier this year. In Shanghai, the Department of disease control initially predicted that the demand for influenza vaccination in autumn and winter this year will increase by about 50% compared with previous years. In this context, whether there will be a contradiction between supply and demand of vaccination this year has also become the focus of attention.

"The validity period of vaccines is only one year. In the past, the vaccines produced by enterprises every year had a relatively high scrap rate. Enterprises were afraid that the vaccines they produced would not be used up, so they did not dare to produce too much." Tao Lina explained that in the past, professionals paid great attention to influenza vaccination, but the public did not pay enough attention to it, so the domestic vaccination situation was not ideal, which also led to low production capacity of enterprises. However, in terms of vaccine supply this year, it is expected that there will be a substantial increase compared with previous years. According to the statistics on the batch issuance of biological products released by the China Academy of food and drug control, as of September 8, more than 15 million doses of influenza vaccines have been approved and issued, including trivalent influenza vaccines, tetravalent influenza vaccines and newly marketed lyophilized nasal spray influenza live attenuated vaccines.

In addition, compared with last year, the number of enterprises approved and issued influenza vaccine increased to 7 this year. According to the information reported by influenza vaccine enterprises, it is estimated that the batch issuance volume of influenza vaccine this year will at least double that of last year. However, experts believe that whether there will be a shortage of supply still depends on the actual vaccination demand this year. About influenza vaccination, these need to know! In principle, all people aged 6 months and above who are willing to receive influenza vaccine and have no contraindications can be vaccinated against influenza. Priority vaccination is recommended for the following key groups: children aged 6 months to 5 years; elderly people aged 60 years and above; patients with chronic diseases; and medical staff. -- timing of influenza vaccination: antibodies with protective level are usually produced after 2 to 4 weeks of influenza vaccination. Individuals are advised to complete vaccination before the epidemic season. For those who have not been vaccinated before the epidemic season, they can also be vaccinated throughout the epidemic season. After vaccination, the protective effect can be maintained for 6 to 8 months, which gradually weakens over time, and influenza virus is prone to mutation.

Therefore, it is recommended to vaccinate influenza vaccine every year. How to choose different vaccines? The number of virus types in trivalent and tetravalent vaccines is different. Tetravalent influenza vaccine has one more type than trivalent vaccine, and the protection range is wider than that of trivalent vaccine, but trivalent vaccine is more economical. Nasal spray vaccine is a newly marketed vaccine, which is attenuated in technology. The vaccine contains live virus. It can simulate the process of natural infection more by nasal spray. No matter what kind of vaccine, all have a preventive effect on influenza. People can choose their own influenza vaccine according to their actual needs. -- the protection rate of influenza vaccine is not 100%, and the protection rate of influenza vaccine is not 100%. Therefore, it is still possible to get influenza after taking influenza vaccine. In autumn and winter, the public should still pay attention to maintaining good personal hygiene habits, including wearing masks, washing hands frequently, paying attention to respiratory tract Etiquette (covering the mouth and nose with paper towel when coughing or sneezing), opening windows for ventilation, balanced diet and moderate exercise; in the influenza epidemic season, high-risk groups should try to avoid going to crowd gathering places.