What disease is bone marrow gray matter vaccine to prevent? What is its mechanism of action?

First, children are vaccinated against polio.

Four doses of polio vaccine are recommended for children. 2 months old, 4 months old, 6- 18 months old and 4-6 years old. IPV provides serum immunity for all three polio viruses, thus preventing paralytic polio.

Second, the mechanism of action Inactivated polio vaccine (IPV) is a common polio vaccine. Polio virus infection can provide lifelong immunity, but this protection is limited to the specific type of polio virus involved (1, 2 or 3). Infection with one type of polio virus cannot protect individuals from the other two types of infection.

IPV is produced by inactivating (killing) wild-type polio virus strains of each serotype with formalin. As an injectable vaccine, it can be used alone or in combination with other vaccines (such as diphtheria, tetanus, pertussis, hepatitis B and Haemophilus influenzae). Generally speaking, the dose is three times apart to produce a sufficient level of seroconversion, and most countries increase the intensive dose in late childhood.

Unlike oral poliovirus, IPV cannot replicate itself, so it is impossible to recover from natural poliomyelitis. In order to make IPV, polio virus was purified and killed with a chemical (formaldehyde). IPV produces antibodies in the blood, not in the intestine. It can prevent the virus from entering the brain or spinal cord through the blood, thus preventing paralysis. In a sense, IPV induces a "second line of defense" against infection because the vaccine induces antibodies in the blood rather than in the intestine.

Third, other polio vaccines-OPV.

Depending on the patient's age, IPV can be injected into the leg or arm. The adverse reactions after taking IPV are very mild and short-lived. Oral polio vaccine (OPV) is also used in other countries. Most studies show that the immune degree of intestinal mucosa is obviously lower than that of OPV, but this difference may not be obvious in the inner layer of pharyngeal mucosa.