What is Polio
Polio (Poliomyelitis) is a serious disease caused by a virus. It’s an infectious illness and generally affects children under 5 years of age.
A person infected with polio virus will experience fever (high temperature), headache, fatigue, nausea or vomiting, stiffness in neck and pain in the arms and legs. The virus may travel to brain and result in permanent paralysis in some people.¹ Out of these few people, a few may even die of paralysis.
How is Polio spread?
The infection generally spreads from person to person.² The main source of infection being, stools (faeces) of the infected person. If even a minuscule amount of stool or droplets from an infected person passes on to non-infected person’s hands, he or she can get infected.
In case of children, the infected child’s stool or droplets can get on to their toy, which may then touch their mouth and the child can become infected.²
Where is Polio found?
With the routine immunization programmes for Polio, this serious illness has been disappeared from the major parts of world.³
World Health Organization (WHO) has declared some parts or the world to be free from Polio, which include – Europe, the United States, the Western Pacific region, and South East Asia.³
However, there are some countries where Polio is still widespread and these countries are Afghanistan, Nigeria, and Pakistan. Polio is considered to be a major problem in these countries and some other countries which are at high risk of developing the infection, include parts of Africa and some countries in Middle East.³
Internationally, IPV is available as single dose vial containing 0.5 ml of vaccine. It is also available as combination vaccine in 4 combinations – IPV + DPT (Diphtheria, Pertussis and Tetanus) or IPV + DPT + Hepatitis B or IPV + DPT + Hepatitis B + Hib (Haemophilus influenzae type b) or IPV + DPT + Hib.4
Who should get the vaccine?
- Children should be given IPV or OPV early in life. The vaccine doses should be given ideally at 6 weeks, 10 weeks, 14-18 weeks, and booster dose at the age of 12-18 months. OPV should be given at birth and subsequent doses later in life, preferably before the child turns 5 years old.
- This schedule might vary for some children, including those who are traveling to certain countries and those who receive IPV as part of combination vaccine.6
- People with a weakened immune system should not get the IPV vaccine, particularly those suffering from chronic illnesses like HIV or cancer
Majority of the times, adults do not need IPV as they have already been immunized during childhood. However, some adults are at a higher risk and should get polio vaccine. These include:
These adults may need about 1-3 doses of IPV, depending on how many doses they have had in the past.
What is the schedule for polio vaccination?
IPV in children:
IPV or the killed polio vaccine is given to children as a continuation of 4 doses. These doses should be given at the age of 6 weeks, 10 weeks, 14-18 weeks and the 4th dose is to be given when the child is between 12-18 months of age.7
|IPV in adults:
|OPV in children:?||
How effective is the medicine?
IPV is very effective and prevents polio, provided, all the recommended doses are completed. A single dose of IPV may provide little or absolutely no immunity, whereas, 99% of people immunized with IPV are protected for lifetime after 3 doses.6
The live polio vaccine – OPV is quite effective and the dose at birth usually does not cause polio paralysis. The vaccine prevents the spread of polio virus to the brain. The vaccine produces antibodies in the intestines (primary site where the polio virus multiplies) which in turn prevent intestinal multiplication of the virus and prevent infection. This explains why mass campaigns with OPV have been considered effective in preventing person-to-person transmission of polio virus.8
Are there any side effects?
Like every medicine, even vaccines may have some side effects. The IPV vaccine is considered to be quite safe; no serious adverse events have been reported.9
Possible side effects may include:
- Slight swelling or redness where the shot is given
- High fever following few hours of vaccination
What if a dose is missed?
If a child gets late for polio vaccine dose, he may get OPV till 5 years of age. Such a kid should receive at least 3 doses. Booster doses should follow these 3 doses – 1st one after 3rd dose and a second booster 3-4 years after the 1st booster, provided the child is still 5 years old till then.¹
1 Open Neurol J. 2016 Aug 31;10:77-82.
2 Anesth Analg. 2016 May;122(5):1450-73.
4 Hum Vaccin Immunother. 2017 Mar 4;13(3):588-598.
6 Hum Vaccin Immunother. 2016 Oct 2;12(10):2690-2693.
7 Pediatr Infect Dis J. 1991 Dec;10(12):970-2.
9 Lancet Infect Dis. 2015 Oct;15(10):1175-82.
10 Pediatr Infect Dis J. 2017 Jan 6.