Live attenuated polio vaccine is a type of vaccine that is designed to provide immunity against poliomyelitis, more commonly known as polio. It is created by weakening the poliovirus through a process known as attenuation, resulting in a milder form of the virus. This weakened or attenuated virus is then used as the basis for the vaccine.
The live attenuated polio vaccine is given orally, typically in the form of drops that are placed on the tongue or swallowed. Once ingested, the weakened virus replicates in the intestines, prompting an immune response from the body. This stimulates the production of antibodies that can recognize and neutralize the actual poliovirus if encountered in the future.
The live attenuated polio vaccine offers several advantages. Firstly, it is highly effective, providing long-lasting immunity against polio. Secondly, it can be administered orally, eliminating the need for injections and making it more convenient, especially for young children. Additionally, since the vaccine virus is passed in the stool of vaccinated individuals, it can contribute to building immunity in unvaccinated individuals through person-to-person contact.
However, there are some potential drawbacks to live attenuated polio vaccine. In rare cases, the weakened virus in the vaccine can regain its ability to cause disease, resulting in vaccine-associated paralytic polio. This risk is extremely low but still exists. Therefore, in some regions where the risk of wild poliovirus transmission is low, inactivated polio vaccine (IPV) is used instead. The IPV does not contain live virus, reducing the risk of vaccine-associated paralytic polio.
