Vaccines

1. Describe the Salk and Sabin vaccines and identify how they differed.
Jonas Salk's vaccine is a clear, colorless sterile suspension for subcutaneous injection. It contains strains of the 3 types of polioviruses originally grown in monkey kidney cell culture and inactivated by exposure to formaldehyde; the vacccine consisted of an injected dose of inactivated (dead) poliovirus. Albert Sabin’s vaccine was taken orally and used attenuated poliovirus; it contains the three serotyped strains of poliovirus. He attenuated the wild type poliovirus by passaging the virus in monkey kidney epithelial cells.
2. Give three advantages and three disadvantages of each vaccine.
Salk’s Advantages:
1. The virus is not live, thus it is easier to manage than Sabin’s.
2. There is no risk of vaccine-associated polio paralysis (VAPP).
3. Immunization triggers an excellent immune response and long-lasting immunity to all 3 poliovirus types.
Salk’s Disadvantages:
1. Offers no protection to the mucosal lining of the intestine, so people vaccinated can still carry the disease and spread it to unvaccinated individuals; ultimately heightening the risk of viral circulation within the community.
2. The price of Salk’s is over 5 times that of Sabin’s.
3. Administering of Salk’s vaccine requires trained health workers.
Sabin’s Advantages:
1. Provided longer lasting immunity than Salk’s vaccine.
2. Sabin’s also indirectly protects other susceptible individuals by secondary vaccination, which means that vaccinated individuals may spread the vaccine virus in the community and thereby inhibit the spread of the wild type virus if it occurs in the population.
3. The Sabin’s vaccine is easily administered by giving children a sugar cube or sugar liquid containing the vaccine, neither of which requires extensive medical training to be administered.
Sabin’s Disadvantages:
1. The risk of vaccine-associated paralytic polio can be a result of the vaccination.
2. In Third World countries, other gastrointestinal viruses interfere with the replication of the attenuated polio vaccine viruses in the intestine of the vaccines.
3. Immunosuppressed individuals shouldn’t take this vaccine and are pushed to take Salk’s if need vaccination.
3. Polio has been eradicated from the US, though it has not been completely eradicated from the rest of the world. Vaccination is still necessary to prevent the return of the disease. Which vaccine do you think should be used for immunizations and why?
The oral vaccination founded by Albert Sabin should be used to prevent Polio because it provides longer lasting immunity, is cheaper and easier to administer, and this method protects other individuals from being susceptible to you. Salk’s vaccine allows the virus to still be active through the fecal/oral route transmission. If however, you are immunosuppressed and need the vaccine, you should take Salk’s because Sabin’s vaccine can cause the virus to be found in respiratory secretions for several days and in stool for several weeks after vaccination; which would be bad for that type of person.


Reference:
http://www.brown.edu/Courses/Bio_160/Projects1999/polio/vac.html