Vaccines to Prevent Polio:
Polio used to be very common in the U.S. and caused severe illness in thousands of people each year before polio vaccine was introduced in 1955. Most people infected with the polio virus have no symptoms, however for the less than one percent who develop paralysis (cannot move arms or legs) it may result in permanent disability and even death.
There are two types of vaccine that protect against polio: Inactivated Polio Vaccine (IPV) and Oral Polio Vaccine (OPV). IPV, used in the U.S. since 2000, is given as an injection in the leg or arm, depending on age. OPV is taken by mouth. Polio vaccine may be given at the same time as other vaccines.
FOR CHILDREN
Most people should get polio vaccine when they are children.
Children should be vaccinated with four doses of inactivated polio vaccine (IPV) at the following ages:
- A dose at 2 months
- A dose at 4 months
- A dose at 6-18 months
- A booster dose at 4-6 years
- You are traveling to polio-endemic or high-risk areas of the world. Ask your healthcare provider for specific information on whether you need to be vaccinated.
- You are working in a laboratory and handling specimens that might contain polioviruses
- You are a healthcare worker treating patients who could have polio or have close contact with a person who could be infected with poliovirus
- The first dose at any time
- The second dose 1 to 2 months later
- The third dose 6 to 12 months after the second
- OPV is administered orally. It can be given by volunteers and does not require trained health workers or sterile injection equipment.
- The vaccine is relatively inexpensive. In 2011, the cost of a single dose for public health programmes in developing countries was between 11 and 14 US cents.
- OPV is safe, effective, and induces long-lasting immunity to all three types of poliovirus.
- For several weeks after vaccination, the vaccine virus replicates in the intestine, is excreted in the faeces, 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.
FOR ADULTS
Most adults do not need polio vaccine because they were already vaccinated as children. But three groups of adults are at higher risk and should consider polio vaccination in the following situations:
Adults in these three groups who have never been vaccinated against polio should get three doses of IPV:
Adults in these three groups who have had one or two doses of polio vaccine in the past should get the remaining one or two doses. It doesn’t matter how long it has been since the earlier dose(s).
Advantages
Disadvantages
Although OPV is safe and effective, in extremely rare cases (approx. 1 in every 2.7 million first doses of the vaccine) the live attenuated vaccine virus in OPV can cau
- See more at: http://www.polioeradication.org/Polioandprevention/Thevaccines/Oralpoliovaccine(OPV).aspx#sthash.4r5Xkn6H.dpufse paralysis. In some cases it is believed that this vaccine-associated paralytic polio (VAPP) may be triggered by immune deficiency. The extremely low risk of VAPP is well known and accepted by most public health programmes in the world because without OPV, hundreds of thousands of children would be crippled every year.
A second disadvantage is that very rarely the virus in the vaccine may genetically change and start to circulate among a population. These viruses are known as circulating vaccine-derived polioviruses (cVDPV).
Safety
OPV is an extremely safe vaccine. All OPV used in supplementary immunization
- See more at: http://www.polioeradication.org/Polioandprevention/Thevaccines/Oralpoliovaccine(OPV).aspx#sthash.4r5Xkn6H.dpuf
activities for the Global Polio Eradication Initiative is pre-qualified by WHO and procured through UNICEF. In 2006, WHO issued a statement to affirm the quality and safety of OPV.
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| Oral polio vaccine is usually provided in vials containing 10–20 doses of vaccine. A single dose is usually two drops |
Efficacy
OPV is highly effective against all three types of wild poliovirus. When this vaccine is used however, there is competition among the three viruses to cause immunity, which results in protection but not with equal efficiency for each type: it is most effective against type 2.
One dose of OPV produces immunity to all three poliovirus serotypes in approximately 50% of recipients. Three doses produce immunity in more than 95% of recipients. Immunity is long-lasting and probably life-long.
One dose of OPV produces immunity to all three poliovirus serotypes in approximately 50% of recipients. Three doses produce immunity in more than 95% of recipients. Immunity is long-lasting and probably life-long.
Recommended use
In most countries, OPV remains the vaccine of choice in routine immunization schedules and supplementary immunization activities.
Where more than one type of wild poliovirus is circulating, OPV is epidemiologically and operationally the best vaccine to use because protection develops to each of the three types of polio virus.
Where more than one type of wild poliovirus is circulating, OPV is epidemiologically and operationally the best vaccine to use because protection develops to each of the three types of polio virus.
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