Visit the laboratory of avian influenza vaccine development in China

Introduction: CCTV focus interview broadcast the program of visiting China's avian influenza vaccine development laboratory on November 26 The following is the content of the program: the beginning of the host Studio: since the Ministry of Agriculture announced the H5N1 avian influenza epidemic in migratory birds in Gangcha County, Qinghai Province in May this year, some places have also suffered from the epidemic In order to effectively prevent the spread and spread of highly pathogenic avian influenza and resolutely block the infection of avian influenza to human beings, the development and promotion of highly effective and safe vaccine has become the key to prevent and control highly pathogenic avian influenza So what about the development of avian influenza vaccine in our country? Text: Reporter's on-the-spot report: This is hanguhe Town, molida vadaur Autonomous Banner, Inner Mongolia Autonomous Region Behind me is Wulan village where the bird flu epidemic occurred on November 15 On November 15, a chicken raised by a villager in this village suddenly died of unexplained causes After that, it was confirmed as H5N1 subtype highly pathogenic avian influenza by the National Avian Influenza Reference Laboratory After the outbreak, The local government has taken prompt measures to control the epidemic Up to now, there has been no new epidemic or human infection for five consecutive days from November 22 With permission, we went to Wulan village with the anti epidemic personnel In the village of 210 families, there is no poultry now After the outbreak, all the birds in the epidemic area have been killed At the same time, the local authorities also carried out emergency immunization of poultry in the threatened areas, which is also a key link to control the epidemic Five kilometers away from the epidemic area belongs to the threatened area In Dongxing village, five kilometers away from Ulan village, the reporter saw that the local epidemic prevention personnel were strengthening the immunity of the poultry here Interview with Wang zhuangfen (Dongxing village villager): reporter asked: how many chickens does your family raise in all? A: there are eight questions: are all the chickens vaccinated? A: all of them have been vaccinated Otherwise, I would have been worried about them earlier Now I can let go after the vaccination Q: where did you get this vaccine from now? A: it's from the flag Q: are all H5N1 vaccines developed by Harbin Veterinary Research Institute? A: Yes Interview with Xu Yanhui (chief of veterinary workstation of Inner Mongolia Autonomous Region): because the threatened areas have been vaccinated, so there is no new epidemic situation now, but we are more anxious, especially in the areas where the vaccine has not been vaccinated, we are eager to supply a large number of vaccines to us It is understood that the avian influenza vaccines used in all epidemic areas and key prevention and control areas are developed by Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, where the National Avian Influenza Reference Laboratory is located When the reporter came here, he saw that the staff were working hard The reporter appeared in P3 laboratory and explained: now the staff led us to the P3 Laboratory of Harbin Veterinary Research Institute Every suspected case of avian influenza in the country needs to be analyzed, identified and finally confirmed in this laboratory Explanation: there are very strict procedures for entering P3 lab, because there are some more dangerous experiments in this lab (reporter registers and puts on protective clothing) reporter's on-site commentary: OK, now I wear it even if it meets the requirements Today, we are allowed to enter the central control room of P3 Laboratory for shooting The staff here tell us that it is the first time that journalists are allowed to enter the laboratory for shooting since its completion So later, the picture we see will be presented to the audience for the first time (the reporter enters P3 central control room) the reporter asks through the walkie talkie: is this even entering the experimental area? The staff replied: Yes Q: is this the central control room? A: Yes Q: the experimenters are doing the experiment, aren't they? A: Yes Hello, will our interview disturb your work or bring you danger? Guan Yuntao (P3 laboratory researcher): it won't cause danger to our whole experiment It doesn't matter Q: let's be as brief as possible What are you doing now? A: This is the suspected case materials sent from the epidemic area We are in the process of (virus) isolation and identification Q: since the outbreak of avian influenza, how long do you have to stay in P3 laboratory every day? A: like Mr Shi, who has been here for more than 10 hours every day since November 11 Q: are you afraid to face the virus directly for such a long time? A: there is no feeling of fear Explanation: in Harbin Veterinary Research Institute, we found that although the outbreak of avian influenza is fierce, the researchers here are very calm Interview with Kong Xiangang (director of Harbin Institute of veterinary medicine, Chinese Academy of Agricultural Sciences): I don't think it's necessary to cause panic at present, because our research on avian influenza has a history of more than ten years At present, some technical reserves for prevention are very mature, which can effectively control the occurrence of avian influenza [NextPage] explained that the calm of the original researchers stems from more than ten years of research on avian influenza In the early 1980s, Harbin Veterinary Research Institute began to study the diagnosis of avian influenza In 1994, Yu Kangzhen, the current head of the national animal husbandry and veterinary station, established the research center of avian influenza in Harbin Veterinary Research Institute and began to carry out systematic research on avian influenza Chen Hualan, now director of the National Avian Influenza Reference Laboratory, was in his 20s and was a doctoral student of Yu Kangzhen Interview with Chen Hualan (director of National Avian Influenza Reference Laboratory): He (Yu Kangzhen) thought that avian influenza (Research) was a work worthy of carrying out at that time He had several outbreaks of avian influenza in other developed countries and spent a lot of manpower and material resources to kill it He thought that if our country as a developing country wanted to kill like that, it might not be able to kill If it was not well controlled and not thoroughly killed, it would be OK It would be more difficult, so he carried out a series of research including vaccine research Narrator: at that time, Chen Hualan only followed the teacher to finish the research She didn't think too much about what the teacher was worried about In 1999, Chen Hualan went to the United States federal Centers for disease control, where he worked on the research of human avian influenza virus The center has world-class experimental conditions, where three years of professional training laid the foundation for Chen's future work During her study in the United States, Chen Hualan received a call from Yu, who hoped that she would return home to take charge of the work of the Avian Influenza Laboratory of Harbin Veterinary Research Institute Continue to interview Chen Hualan (director of National Avian Influenza Reference Laboratory): I remember to call him later, he said: have you arrived in Beijing? I'll see you He said: have you arrived in Beijing? That means I feel like I should be back Explanation: at that time, the federal Centers for Disease Control tried to keep Chen Hualan and told her that if she stayed in the United States, she would become a very good scientist However, Chen Hualan finally chose to return home Continue to interview Chen Hualan (director of National Avian Influenza Reference Laboratory): I want to be in the United States, even if I stay, I want to be a good scientist until now, that is to say, I will send some beautiful articles, but I may still be a small molecule in the whole laboratory system, only doing a very single job; I may come back and combine all my ideas with the needs of the country, and I will decide to do it What and how to do In addition, a motivation for me to come back - which is real - I think our country needs these technologies In 2002, Chen Hualan returned to Harbin Veterinary Research Institute At that time, H5N2 avian influenza vaccine had been developed successfully The immune effect of this vaccine was very good for chickens, but not ideal for ducks, geese and waterfowls Under the leadership of Chen Hualan, researchers began to develop H5N1 avian influenza vaccine, which has a good immune effect on chickens and waterfowls The first thing we need to do is to match the virus strain At that time, the H5N1 avian influenza virus isolated in our country was highly pathogenic, which was not suitable for vaccine How to get a suitable vaccine strain is a difficult problem Chen Hualan and his researchers, after four years' efforts, boldly adopted the development idea of human influenza vaccine, and solved this problem Continue to interview Chen Hualan (director of the National Avian Influenza Reference Laboratory): we use the latest reverse gene operation technology, to put it bluntly, it's a human-made technology to build influenza virus, and create a virus that more matches the antigenicity of the H5N1 subtype avian influenza virus that is prevalent in our country There are two viruses on this screen This virus is H5N1 subtype avian influenza virus When we made this vaccine strain, we took two genes: one is the HA gene, the other is the NA gene, and its HA gene has some sites related to the pathogenicity We use the red dot to indicate that we lost these sequences related to the pathogenicity, and then we lost them again Using six internal genes of PR8 virus, PR8 virus is an early virus isolated from human, and then we put these two fragments and these six fragments together to transfect into cells to create such a H5N1 / PR8 recombinant virus It is a low disease causing strain, which can grow very well on chicken embryos, so it is an ideal vaccine Strain Q: and then use it to make H5N1 avian influenza vaccine? A: Yes Explanation: at present, H5N1 and H5N2 avian influenza vaccines are widely used in China, and the live fowlpox vector vaccine is also used Compared with the first two vaccines, it is cheaper to produce Interview with Kong Xiangang (researcher in charge of Harbin Institute of veterinary medicine, Chinese Academy of Agricultural Sciences): the H5N1 and H5N2 vaccines in front are inactivated vaccines The cost of this inactivated vaccine is relatively high, so this live fowlpox vector vaccine is only one third of the price of the first two vaccines, which can reduce the burden of farmers, improve their income, and increase their immunization intensity Explanation: in the interview, researchers often say that there will never be the best vaccine Although there have been three kinds of avian influenza vaccines, researchers have not satisfied with them The fourth latest bivalent vaccine of avian influenza Newcastle disease has been developed and put into production recently Newcastle disease is commonly known as "chicken plague" in our country Like highly pathogenic avian influenza, Newcastle disease will cause large-scale death of poultry Interview with Bu Zhigao (researcher of Harbin Institute of veterinary medicine, Chinese Academy of Agricultural Sciences): the biggest characteristics and advantages of this vaccine