Currently there are two types of polio vaccines; inactivated poliovirus vaccine (IPV) and oral poliovirus (OPV). Since 2000 the United States has established that only IPV is to be used, even though in many parts of the world the OPV is still being used. The IPV, inactivated poliovirus vaccine, is an injected vaccine. IPV generates serum antibodies to neutralize the virus in the bloodstream before it reaches the CNS. The OPV, live attenuated oral poliovirus vaccine, develops local mucosal immunity in the G.I. tract to prevent spread of the virus into the bloodstream. The reason the United States has decided to only utilize IPV vaccine is the documented risk of using OPV, the attenuated virus is very high. OPV, a live attenuated vaccine, retains the capacity for transient growth within the inoculated host. Even though the OPV vaccine often provides lifelong immunity it comes at a extreme risk, that it may revert to a virulent form which can be fatal to immunocompromised individuals and pregnant women (potential risk to the fetus). When OPV is ingested, the virus replicates within the GI tract to provide immunity to subsequent infection. Typically, the revertant viruses are shed through the feces but in rare cases the revertant viruses cause poliomyelitis, VAPP (vaccine-associated paralytic poliomyelitis). When the United States terminated the use of the OPV vaccine and started using the IPV vaccine in 2000, VAPP was
Currently there are two types of polio vaccines; inactivated poliovirus vaccine (IPV) and oral poliovirus (OPV). Since 2000 the United States has established that only IPV is to be used, even though in many parts of the world the OPV is still being used. The IPV, inactivated poliovirus vaccine, is an injected vaccine. IPV generates serum antibodies to neutralize the virus in the bloodstream before it reaches the CNS. The OPV, live attenuated oral poliovirus vaccine, develops local mucosal immunity in the G.I. tract to prevent spread of the virus into the bloodstream. The reason the United States has decided to only utilize IPV vaccine is the documented risk of using OPV, the attenuated virus is very high. OPV, a live attenuated vaccine, retains the capacity for transient growth within the inoculated host. Even though the OPV vaccine often provides lifelong immunity it comes at a extreme risk, that it may revert to a virulent form which can be fatal to immunocompromised individuals and pregnant women (potential risk to the fetus). When OPV is ingested, the virus replicates within the GI tract to provide immunity to subsequent infection. Typically, the revertant viruses are shed through the feces but in rare cases the revertant viruses cause poliomyelitis, VAPP (vaccine-associated paralytic poliomyelitis). When the United States terminated the use of the OPV vaccine and started using the IPV vaccine in 2000, VAPP was