Let every child rest assured of vaccination.

April 25th this year is the 30th Children’s Immunization Day in China.
Let every child rest assured of vaccination.

April 25th this year is the 30th Children’s Immunization Day in China. The theme is: Vaccinate according to law and enjoy a healthy life. Vaccine is used to prevent diseases in healthy people, and the first requirement of the state is safety. Before the vaccine is registered, it needs to undergo strict animal experiments and clinical research to ensure that it will not cause harm to the vaccinators. Before the vaccine is put on the market, a strict batch issuance system is implemented. Yu Wenzhou, chief physician of the Center for Immunization Planning of China CDC, said that only by ensuring the safety of vaccines can every child be safely vaccinated.

The vaccination rate of the national immunization program is 90%

Yu Wenzhou said that vaccination according to law is the right of every child. No matter in developed cities or remote mountainous areas, despite the differences in the environment of vaccination sites, every child can be guaranteed to be vaccinated safely in China. The vaccination work chain finally extends to the primary vaccination clinic through the district and county level CDC. Vaccination clinics are usually set up in community health service centers or township hospitals, which is the operation link of vaccination. Each vaccine will be vaccinated for school-age people in strict accordance with standardized vaccination procedures.

Since the implementation of planned immunization in China in 1978, the incidence and death of measles, whooping cough, diphtheria, poliomyelitis, tuberculosis and tetanus have been reduced by popularizing children’s immunization. In 2000, China was confirmed to be polio-free. In 2002, the neonatal hepatitis B vaccine was included in the national immunization program; In 2007, the national immunization program was expanded, and hepatitis A vaccine and epidemic cerebrospinal meningitis vaccine were included in the national immunization program, and 14 national immunization program vaccines prevented 15 diseases. In 1988, 1990 and 1996, China’s BCG vaccine, polio vaccine, DTP vaccine and measles vaccine reached the goal of 85% in provinces, counties and townships respectively. At present, the vaccination rate of the national immunization program with townships as the unit has reached the goal of 90%.

Cui Fuqiang, deputy director of the Center for Immunization Planning of China CDC, said that China has established a well-functioning reporting system for suspected adverse reactions of vaccination, and all vaccines currently used have monitoring and statistical data on adverse reactions. All kinds of vaccines used in formal channels are safe and effective.

Vaccine safety problems are directly "killed"

From research and development to injection to human body, a vaccine has to undergo strict safety management to play a role in preventing diseases. The quality standard of vaccine contains safety, effectiveness and other indicators. Vaccine production enterprises produce vaccines under the guidance of good manufacturing practice (GMP), and the State Food and Drug Administration conducts the strictest supervision on vaccine production and implements the batch issuance and release system.

Yang Xiaoming, director of the National Joint Vaccine Engineering Technology Research Center and chairman of China Biotechnology Co., Ltd., said that a vaccine has to go through at least 8 or even 20 years of research and development from research and development to marketing, and the vaccine has to undergo strict animal experiments and clinical research before it is registered, and the vaccine has to implement a strict batch issuance system before it is put on the market. Every link from research and development to production, if there is a safety problem with the vaccine, it will be directly "killed".

Many people believe that imported vaccines are more reliable and safer than domestic vaccines. Yang Xiao said that the revised version of GMP in 2010, which is followed by vaccine manufacturers, can be described as the "Chinese version" of EU GMP. In order to pass this certification, various enterprises have invested heavily, and Sinopharm Zhongsheng has invested nearly 10 billion yuan in hardware upgrade and management improvement. After the promulgation and implementation of the 2010 edition of China Pharmacopoeia, some imported live attenuated vaccines were withdrawn from the domestic market because of antibiotic residues or Vero cell DNA residue standards.

Japanese encephalitis is a disease spread by mosquito bites, which can cause brain inflammation. Vaccination is an effective preventive measure. The vaccine is independently developed in China and has independent intellectual property rights. It was approved by the former Ministry of Health in 1998 and has been used for more than 600 million doses so far, providing effective immune protection for hundreds of millions of children. This is the first vaccine to go abroad in China, the first China vaccine purchased by UNICEF, and the first time that GAVI adopted a vaccine from China to promote epidemic control.

"Fragile" vaccines undergo rigorous and challenging tests.

Because vaccines are sensitive to temperature, every link from the vaccine manufacturing department to the site where vaccines are used may fail due to high temperature. China has established a cold chain system to complete the operation of the vaccine, ensuring that the vaccine has proper refrigeration equipment in the whole process from production, storage, transportation, distribution to use, so that the vaccine is always kept in a prescribed cold state, ensuring that the reasonable titer of the vaccine is not damaged, and the vaccine will not fail due to temperature.

In fact, these seemingly "fragile" vaccines have undergone harsh and challenging tests. Only vaccines that pass challenging tests have a chance to get listed. Generally speaking, the challenge test of vaccine is to make the vaccine accept various harsh challenges such as temperature, light, vibration, repeated freezing and thawing, and even oxidation to see under what conditions it can still remain qualified. Challenge test of vaccine generally includes accelerated stability test and compulsory condition test of vaccine.

In April 2015, china food and drug administration issued the "Technical Guiding Principles for Stability Research of Biological Products", which clearly stipulated the requirements and standards for challenging tests of vaccines. Every vaccine should be challenged in the R&D registration stage before marketing according to this guiding principle. That is, the vaccine is placed at 37 degrees Celsius for a certain period of time (ranging from 2 days to 4 weeks) before it goes on the market. If the decline value of effective components (such as the number of live bacteria, virus titer or titer) is within an acceptable range, and the vaccine as a whole is still qualified, it can be judged that the vaccine is a qualified product, and then released for the market. China Institute for the Control of Pharmaceutical and Biological Products should also check the thermal stability of products when issuing vaccines in batches. The test results can be used as the basis for formulating the validity period and storage conditions of the vaccine.

"Safe vaccines are the most effective." Cui Fuqiang said that the vaccine made human beings take the initiative for the first time in the face of the threat of infectious diseases, and played an irreplaceable role in reducing mortality and improving life expectancy per capita. (Reporter Wang Junping)