Chen Hualan： the ＂flu detective＂ who stopped the virus.

Cctv newsVirus is a word that makes people turn pale and avoid it. However, there is such a scientist who, despite difficulties, has played a key role in successfully stopping the avian influenza epidemics such as H5N1 and H7N9 in China. She is Chen Hualan, director of the National Avian Influenza Reference Laboratory and academician of the Chinese Academy of Sciences.

The National Avian Influenza Reference Laboratory of Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, which she led, built a safety "epidemic prevention wall" by relying on a number of international leading achievements independently developed, and contributed China’s wisdom and strength to the prevention of avian influenza in many countries around the world.

Where is the initial heart?

In 1999, as a postdoctoral fellow, Chen Hualan went to the Influenza Sub-center of the Centers for Disease Control (CDC) in the United States to conduct cooperative research on avian influenza. After the exchange, the other party kindly retained him, but Chen Hualan resolutely embarked on the road of returning home.

"It doesn’t matter if the conditions are backward, we can build it slowly." Chen Hualan said that China is a big country for raising poultry. Once bird flu breaks out, it will inevitably suffer great losses if it lacks effective means. "Since the knowledge and technology I have mastered are urgently needed by the country, why don’t I come back?"

Highly pathogenic avian influenza is a class A infectious disease. Once the bird flu epidemic is found all over the world, the common way is to cull all the poultry in a certain range. Doing so not only consumes huge human and financial resources, but also brings disaster to the aquaculture industry.

"Why not seek a better solution?" Chen Hualan, who has just returned to China, boldly proposed, "It is ‘ to develop a new and efficient vaccine for prevention and control; Four or two thousand catties ’ The best choice. " The laboratory she led was designated as the "National Reference Laboratory for Avian Influenza" by the Ministry of Agriculture, responsible for the epidemic diagnosis, epidemiological monitoring and prevention and control technology research of highly pathogenic avian influenza.

At the beginning of 2004, H5 subtype highly pathogenic avian influenza raided 14 provinces in China. The National Reference Laboratory for Avian Influenza receives samples from all over the country for final identification every day. In a short time, more than 50 cases of highly pathogenic H5N1 avian influenza were diagnosed, which played a key role in controlling the epidemic in time.　

Chen Hualan led the team to speed up the pace of vaccine research and development. In more than a year, they completed the research on the new avian influenza vaccine in the laboratory. The successful development of H5N1 and H5N1 avian influenza vaccines has greatly improved China’s ability to prevent and control avian influenza and saved tens of billions of yuan for the country.

Re-war virus

In March 2013, there were cases of human infection with H7N9 avian influenza in China. The rapid spread of the virus caused a lot of panic in the country and attracted great attention from the international community.

The epidemic situation is like military intelligence, and Chen Hualan has once again started a race against the virus. She and her colleagues sent a number of teams to take samples at the first time, and then immediately conducted research and analysis.

Less than 48 hours after the first infected case was announced, Chen Hualan’s team isolated a similar virus from the samples collected in the live poultry market. According to the research results, Chen Hualan suggested that the live poultry market in infected areas should be closed immediately. After her suggestion was adopted, the number of new infections decreased rapidly.

"Although the H7N9 virus that appeared in 2013 can infect people, it is not pathogenic to poultry, and chickens do not show any clinical symptoms after infection, which makes it difficult to find the virus in time." Chen Hualan later said.

The H7N9 avian influenza virus caused a total of 5 waves of human infections, resulting in 1,567 infections, of which more than 600 people were killed. From October every year to March the following year, it is a high incidence period of human infection with H7N9 avian influenza.

Chen Hualan said: "At the thought that H7N9 avian influenza virus is threatening the lives of thousands of people, we dare not relax for a moment."

In the four Spring Festival after the emergence of H7N9 virus, Chenhualan was spent in the laboratory. But the virus is a tough opponent.

"In January 2017, we found in the monitoring that the H7N9 avian influenza virus had a key mutation, and poultry began to get sick and died in large numbers after infection." The situation that Chen Hualan is most worried about has emerged. "The mutated virus is more harmful to people, and the mortality rate can reach more than 50%."

From January to September, 2017, the "race" between team Chen Hualan and the virus entered a sprint stage: intensify on-site sample collection and pathogen monitoring nationwide, speed up virus analysis and research, formulate prevention and control measures, put forward prevention and control suggestions, speed up the process of creating efficient vaccines, and accept evaluation and testing & HELIP; … Miracle happened like this. Before the arrival of the virus epidemic season in autumn and winter of 2017, Chen Hualan team successfully launched the bivalent inactivated vaccine of recombinant avian influenza virus (H5/H7).

The popularization of the vaccine has effectively controlled the spread of H7N9 avian influenza virus in poultry and successfully blocked the infection of H7N9 avian influenza virus in people.

be as usual

Behind the first-class scientific research is the unimaginable contribution of ordinary people. Team Chen Hualan conducts large-scale avian influenza virus monitoring twice a year, and members go to farms and live poultry markets across the country to take samples from live poultry and bring them back for analysis. When sampling, researchers should use swabs to take samples from the deep throat and cloaca of chickens respectively. In 2017 alone, the team members sampled 53,000 copies. After returning to the laboratory, they must isolate the virus as soon as possible and do further analysis and research.

In addition to epidemic diagnosis and vaccine research, Chen Hualan also led the team to strengthen the active surveillance of avian influenza epidemiology in China and explore the biological characteristics of the virus. By giving full play to the individual strengths of team members, a full chain and systematic influenza research layout has been formed. At the same time, it shoulders the responsibility of providing scientific reference for the prevention and control of bird flu epidemic and early warning of human influenza.

In 2013, Chen Hualan was selected as one of the top ten scientific figures in Nature, and Nature called her "the one fighting in the front line ‘ Influenza detective ’ " . In 2016, Chen Hualan won the "World Outstanding Female Scientist Achievement Award" awarded by UNESCO.

Even though Chen Hualan has stood in the leading position in the world, he and his team are always in a state of "preparing for war". Chen Hualan said: "Avian influenza virus can infect not only poultry, but also migratory birds. Migratory birds who migrate across borders are very free, and they don’t need to fly to any country ‘ Passport ’ . If they carry the virus, an epidemic may occur as soon as they come into contact with local poultry. We must always be vigilant and respond to emerging epidemics at any time. "

Now, the word "avian influenza" has quietly faded out of the sight of ordinary people, while Chen Hualan remains vigilant. "The highly pathogenic avian influenza virus has evolved rapidly, and we can’t relax at all". Some people ask, is it worthwhile to give up many pleasures in life for work? Chen Hualan replied slowly: "Is it more fun and worthwhile for researchers engaged in the prevention and control of infectious diseases to nip the highly dangerous bird flu epidemic in the bud?" (Text/Kan Chunyu)