Poliovirus and Polio Vaccines

Last Updated on January 20, 2020 by Sagar Aryal

Poliovirus

It is an infectious disease caused by poliovirus which affects the spinal cord and brain stem, it leads to paralysis and even leads to death.

• Poliovirus is the causative agent of poliomyelitis.
• Children under 5 years of age are more susceptible to this disease.
• Reservoir Human.
• Spread through feces.
• Contaminated food and water.
• So, it spread in the communities with poor infrastructure.
• Poor sanitation.
• Crowded living conditions.
• Young children are particularly at risk of infection.

History and epidemiology

• Poliovirus was first described by MICHAEL UNDERWOOD in 1789.
• The first outbreak described in the U.S in 1843.
• 21000 paralytic cases were reported in the U.S in 1952.
• Polioviruses are distributed globally before the availability of immunization, almost 100% of the population in developing countries before the age of 5.
• The availability of immunization and the poliovirus eradication campaign has eradicated poliovirus in most regions of the world except in the Indian subcontinent and Africa.
• In 1908 transmission of polio to a monkey by Landsteiner was confirmed. The virus was grown on tissue culture in 1949.
• Three types of poliovirus were isolated and identified in 1951.
• Trials of Salk vaccine: The first large scale trial of Salk was performed in 1954. The use of Sabin in 1958 first general use of Sabin was done.
• As a result of the massive global vaccination campaign over the past 20 years, polio exists only in a few countries in Africa and Asia. In the Philippines, the last case was reported in 1993 and in 2000 the Philippines was certified as a polio-free country.

Image Source: Wikipedia and JAMA Forum

Types of polio vaccine

Inactivated Polio Vaccine

• Synonyms for IPV vaccine
• e-IPV
• ep-IPV
• Salk vaccine
• IPV is a trivalent (strains 1,2,3) vaccine.

Salk Polio Vaccine

– Jonas firstly developed the Salk vaccine

1) Formaldehyde-fixed

2) Non-reversion (this inactivated polio vaccine cannot revert back, np side effect and safe to use).

3) types of poliovirus grown in monkey kidney tissue culture.

Procedure for preparation

• Standard virulent strains used.
• 3 types of polio vaccines grown separately in MKTC.
• Adequate titer filtered to remove debris and clumps.
• Inactivated with formalin at 37 degrees for 12-15 days.
• Stringent tests to ensure complete inactivation
• Issued for use.

History

• In 1954 the whole USA was vaccinated against polio and 80-90% population was protected.
• In 1955 100 cases of poliomyelitis were reported due to the insufficiently inactivated vaccine.

Merits

• IPV produces antibodies in the blood to all three types of poliovirus.
• As IPV is not a live vaccine, it carries no risk of VAPP.
• IPV triggers an excellent protective immune response in most people. • Shipping and transport are easy.

Demerits

• IPV is over 5 times more expensive than OPV
• A booster regime is required.
• Do not stimulate local and mucosal immunity
• Administering the vaccine requires trained workers, as well as sterile injection, equipment, and procedure.

Oral Polio Vaccine

• Trivalent oral polio vaccine.
• A synonym is the Sabin vaccine.
• Developed by Albert Sabin in 1961.
• It is a live attenuated virus vaccine.
• Oral administration of vaccine yields a local gastrointestinal infection.
• A major caution with TOPV is that it is a live vaccine and must never be injected.

Preparation

• Attenuated by a passage in the foreign host (MKC)
• Selection to grow in new in host makes viruses.
• Less sited to the original host.
• Stabilizers such as sucrose or trehalose or arginine hydrochloride may be added to retain the antigenicity.
• Inactivation is carried out by adding formalin at 0.025% concentration.
• Incubation at 37centigrade up to 48 hours and then at 23 centigrade up to 12 days.
• Test for free formaldehyde content after 12 hours consistent inactivation of the virus is monitored and verified.

Advantages

• Oral polio vaccines are easily administered, with no need for highly trained.
• Induce both humoral and systemic immunity.
• Antibodies quickly produce as 1 or 2 doses of oral vaccine can give 90-100% results.

Disadvantages

• Instability at high temperature.
• Very small residual neurovirulence in OPV.
• Frequent vaccine failure even with fully potent.

Storage of polio vaccine (OPV and IPV)

• OPV is a heat sensitive vaccine.
•  Stored at -20 degrees.
• Having shelf life…
• 2 years at -20 degree
• 6 months at 2-8 degree
• 1-3 days at room temp.

References

• https://en.wikipedia.org/wiki/Polio_vaccine.
• https://www.cdc.gov/vaccines/vpd/polio/public/index.html.
• https://www.who.int/biologicals/areas/vaccines/polio/opv/en/.
• http://polioeradication.org/polio-today/polio-prevention/the-vaccines/ipv/.
• https://immunizationforwomen.org/providers/diseases-vaccines/poliomyelitis/vaccine-recommendations-safety.php.
• https://www.britannica.com/science/polio-vaccine.
• https://www.vaccines.gov/diseases/polio.

Sources

• 16% – https://www.slideshare.net/Muhammadiqbal583/polio-vaccine-85407875
• 6% – https://judoctor2011.files.wordpress.com/2014/02/lecture-3.pdf
• 3% – https://www.slideshare.net/leehimangsu13/poliomyelitis-53216812
• 3% – https://quizlet.com/85252674/mc_f2-flash-cards/
• 3% – http://polioeradication.org/polio-today/polio-prevention/the-vaccines/ipv/
• 2% – https://www.medicinenet.com/polio_facts/article.htm
• 2% – http://www.freepatentsonline.com/y2008/0193478.html
• 1% – https://www.vaccines.gov/basics/types
• 1% – https://www.smartparenting.com.ph/health/your-kids-health/polio-outbreak-philippines-a00228-20190922-lfrm
• 1% – https://www.sciencedirect.com/topics/medicine-and-dentistry/poliomyelitis
• 1% – https://medlineplus.gov/polioandpostpoliosyndrome.html
• 1% – http://www.allindianpatents.com/patents/231047-a-process-for-the-preparation-of-polio-vaccine
• <1% – http://dictionary.sensagent.com/Polio%20vaccine/en-en/

Poliovirus and Polio Vaccines