Mozambique confirms first wild poliovirus case in 30 years

Context

Mozambique identified its first case of wild poliovirus Type 1 after a child contracted the disease. 

• It is the country’s first such case since 1992 and the second imported case of wild poliovirus in Southern Africa this year. 

What is polio?

• Polio is a crippling and potentially deadly disease that affects the nervous system.
• The virus is transmitted by person-to-person, spread mainly through the faecal-oral route or, less frequently, by a common vehicle (e.g. contaminated water or food) and multiplies in the intestine, from where it can invade the nervous system and can cause paralysis.
• Once that happens, the patient is crippled for life because there is no treatment for the affliction.
• Polio infection, however, is easily preventable by a vaccine.
• Polio may be fatal if the muscles used for breathing are paralysed or if there is an infection of the brain.

Variants of the poliovirus

• There are three variants of the poliovirus, numbered 1 to 3:
• 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.
• For a country to be declared polio-free, the wild transmission of all three kinds has to be stopped.
• For eradication, cases of both wild and vaccine-derived polio infection have to be reduced to zero.

Polio cases in India

• India was declared polio-free in January 2014, after three years of zero cases.
• The last case due to wild poliovirus in the country was detected on January 13, 2011.
• The WHO on February 24, 2012, removed India from the list of countries with active endemic wild poliovirus transmission.
• India launched the Pulse Polio immunisation programme in 1995, after a resolution for a global initiative of polio eradication was adopted by the World Health Assembly (WHA) in 1988.
• To prevent the virus from coming to India, the government has since March 2014 made the Oral Polio Vaccination (OPV) mandatory for those travelling between India and polio-affected countries, such as Afghanistan, Nigeria, Pakistan, Ethiopia, Kenya, Somalia, Syria and Cameroon.