Polio is an infectious disease which has been infected people all around the globe and is still infecting individuals who belong to under developed or developing countries. Polio is caused by a virus which lives in a person’s throat or intestinal tract. This illness used to be very common in US and caused severe illness in thousands of people each year before the introduction of polio vaccination. The illness is contagious as it can easily be spread by the contact with the stool of infected person and also through oral or nasal secretions.
Polio vaccine was introduced in 1955 and proved very much useful in the prevention of polio. People, who used to get affected by the polio virus, generally had no symptoms. A very small population used to develop paralysis which resulted in permanent disability and caused death in some cases, too.
What are the types of Polio Vaccine?
Polio vaccines are of two types which prevent polio by inactivating the polio virus. Types of polio viruses are:
1. Inactivated polio Vaccine (IPV)
2. Oral poliovirus vaccine (OPV)
Inactivated polio Vaccine is in the form of an injection which is injected in the leg or the arm of the patient depending on their age. When the person is given other vaccines, the polio vaccine can also be given along with them. Mostly the children are vaccinated with polio vaccine when they are too young.
Children get four doses of inactivates polio vaccine at the age of 2 months, 4 months, 6-18 months and 4-6 years. The last dose is known to be as booster dose.
Oral polio vaccine (OPV) is still used in many countries of the world but it has not been used in US since year 2000.
Advantage of Oral Polio Vaccine
As depicted from its name, it is administrated orally and can also be given by the volunteers as it does not require trained health workers or sterile equipments such as injections etc.
For several weeks after vaccination, the vaccine virus replicates in the intestine, is excreted in the feces, and can be spread to others in close contact. This means that in areas where hygiene and sanitation are poor, immunization with OPV can result in the passive immunization of people who have not been directly vaccinated.
Another advantage of Oral Polio Vaccine is, it is less expensive. In 2015, the cost of this vaccine was 14-16 US cents in developing countries.
Oral polio vaccine is effective and safe and it induces long lasting immunity to all types of the polio.
Recommended use of Oral Polio Vaccine (OPV)
Oral polio vaccine remains the vaccine of choice in routine immunization schedules and supplementary immunization activities, in most countries. Where more than one type of wild poliovirus is circulating, OPV is epidemiologically and operationally the best vaccine to use because it develops protection and prevention against all the three types of the polio viruses.
Advantages of Inactivated polio Virus (IPV)
Inactivated polio Virus causes a successful and excellent prevention and immunization in most of the people.
Inactivated polio Virus is not a live vaccine so it can carry no risks of vaccine related polio vaccine.
Recommended use of inactivated polio Virus (IPV)
Inactivated polio Virus vaccine is being used on a huge scale in industrialized countries for making them polio free countries as a vaccine of choice because the risk of polio associated paralysis
However, as IPV does not stop transmission of the virus, oral polio vaccine is used wherever a polio outbreak needs to be contained, even in countries which rely exclusively on IPV for their routine immunization program.