World Polio Day 2020 | 27 Oct 2020

Why in News

Every year, 24th October is observed as World Polio Day in order to call on countries to stay vigilant in their fight against the disease.

  • It was established to commemorate the birth of Jonas Salk, who developed an Inactivated (killed) Polio Vaccine (IPV).

Key Points

  • In the last three decades, the Global Polio Eradication Initiative (GPEI), led by national governments and the World Health Organisation (WHO), has been monitoring the disease situation globally.
  • As per the WHO, since 1980, the cases of wild poliovirus have decreased by over 99.9% as a result of vaccination efforts made around the world.
  • Polio Eradication:
    • For a country to be declared polio-free, the wild transmission of all three kinds of Polioviruses has to be stopped.
    • For eradication, cases of both wild and vaccine-derived polio infection have to be reduced to zero.
      • Eradication of a disease refers to the complete and permanent worldwide reduction to zero new cases through deliberate efforts. If a disease has been eradicated, no further control measures are required.
      • However, elimination of a disease refers to reduction to zero or a very low defined target rate of new cases in a defined geographical area. It requires continued measures to prevent re-establishment of disease transmission.
  • Recent Outbreaks:
    • In 2019, polio outbreaks were recorded in the Philippines, Malaysia, Ghana, Myanmar, China, Cameroon, Indonesia and Iran, which were mostly vaccine-derived in which a rare strain of the virus genetically mutated from the strain in the vaccine.
      • According to the WHO, if the oral vaccine-virus is excreted and allowed to circulate in an unimmunised or under-immunised population for at least 12 months, it can mutate to cause infections.
    • Afghanistan and Pakistan are the two countries that are the last stronghold of the wild poliovirus.
  • Polio in India:
    • India received polio-free certification by the WHO in 2014, after three years of zero cases.
      • This achievement has been spurred by the successful pulse polio campaign in which all children were administered polio drops.
      • The last case due to wild poliovirus in the country was detected on 13th January 2011.

Polio

  • About:
    • Polio is a crippling and potentially deadly viral infectious disease that affects the nervous system.
    • There are three individual and immunologically distinct wild poliovirus strains:
      • Wild Poliovirus type 1 (WPV1)
      • Wild Poliovirus type 2 (WPV2)
      • Wild Poliovirus type 3 (WPV3)
    • Symptomatically, all three strains are identical, in that they cause irreversible paralysis or even death.
    • However, there are genetic and virological differences, which make these three strains separate viruses which must each be eradicated individually.
      • WPV2 and WPV3 have been eradicated globally but WPV1 remains in circulation in Afghanistan and Pakistan.
        • WPV2 was eradicated in 1999.
      • World Polio Day 2019 marked a milestone in polio eradication as the independent Global Commission for the Certification of Poliomyelitis Eradication (GCC) declared WPV3 to be globally eradicated.
  • Spread:
    • The virus is transmitted by person-to-person mainly through the faecal-oral route or, less frequently, by a common vehicle (for example, through contaminated water or food).
    • It largely affects children under 5 years of age.
    • The virus multiplies in the intestine, from where it can invade the nervous system and can cause paralysis.
  • Symptoms:
    • Most people with polio do not feel sick. Some people have only minor symptoms, such as fever, tiredness, nausea, headache, nasal congestion, sore throat, cough, stiffness in the neck and back, and pain in the arms and legs.
    • In rare cases, polio infection causes permanent loss of muscle function (paralysis).
    • Polio can be fatal if the muscles used for breathing are paralysed or if there is an infection of the brain.
  • Prevention and Cure:
    • There is no cure, but it can be prevented through immunisation.
  • Vaccines:
    • Oral Polio Vaccine (OPV): It is given orally as a birth dose for institutional deliveries, then primary three doses at 6, 10 and 14 weeks and one booster dose at 16-24 months of age.
    • Injectable Polio Vaccine (IPV): It is introduced as an additional dose along with the 3rd dose of DPT (Diphtheria, Pertussis and Tetanus) under the Universal Immunisation Programme (UIP).

Source: IE