Two types of vaccines for polio have been developed, an inactivated whole (Salk) and a live attenuated (Sabin) vaccine. Compare and contrast the advantages and disadvantages of the two polio vaccines
What will be an ideal response?
The inactivated whole vaccine does not replicate and, therefore, does not cause an infection, which has both advantages and disadvantages: The Salk vaccine does not cause polio, but it requires boosters and elicits primarily an antibody (humoral) response, which is less effective in fighting viral pathogens than are cell-mediated immune responses. The Salk vaccine also must be administered by injection.
The attenuated live vaccine replicates and therefore establishes an infection. The advantages to this vaccine are that it requires only a single dose and produces a cell-mediated immune response. The vaccine is easily administered orally. The oral dose mimics the normal route of infection (polio is an enteric virus) and potentially produces a more appropriate immune response. The vaccine can produce contact immunity. The disadvantages of the Sabin vaccine are that it can cause polio in a small number of vaccinees (about 1 in every 2 million vaccinees) and their contacts and that it can revert to wild-type virulence and spread throughout the population. Consequently, the live attenuated vaccine is no longer used in the United States.
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Pia mater, arachnoid mater, dura mater Dura mater, arachnoid mater, pia mater Arachnoid mater, pia mater, dura mater Arachnoid mater, dura mater, pia mater