Why is the common memory sugar pill vaccine after 80s almost invisible now?

Sugar pill is an effective control method to prevent and eliminate polio. Polio vaccine is used to prevent poliomyelitis, and poliomyelitis sugar pills are being used in China. The main components of the live polio vaccine sugar pill are polioviruses I, II and III, and the auxiliary materials include syrup, milk powder, cream, glucose powder and sucrose powder.

From the point of view of prevention, there is still no need to take trivalent sugar pills including type II. Zhang Shiying, director of the immunization planning department of Shenzhen Center for Disease Control and Prevention, said that there are three kinds of wild viruses in polio. There were three kinds of oral sugar pills, but type II was eliminated worldwide as early as 1999, so it is not necessary to continue taking them.

On the contrary, continuing to take it will bring some dangers. Zhang Shiying said that containing type II vaccine will lead to some cases caused by polio vaccine.

Official website, the National Health and Family Planning Commission, showed that at present, wild poliovirus cases are mainly caused by type I, and type II polio cases are caused by vaccine strains. From 2000 to 20 14, there were 77 cases1case of vaccine-derived poliovirus in the world, including 679 cases of type II, accounting for 88% of the total. It can be seen that it is imminent to stop using type II vaccine.

In fact, this polio vaccine conversion is a global action. In 20 15, after the World Health Organization announced the elimination of wild poliovirus type II, it decided to stop using trivalent live attenuated polio vaccine worldwide and switch to bivalent live attenuated polio vaccine containing serotypes I and III, and at the same time required all countries to introduce at least one dose of inactivated polio vaccine. This adjustment is aimed at 155 countries that still use live attenuated polio vaccine, and China is one of them.