2 out of 3 wild poliovirus strains have been eradicated, says WHO

News:On the World Polio Day,independent Global Commission for the Certification of Poliomyelitis Eradication(GCC) has declared that wild poliovirus type 3(WPV3) has been eradicated worldwide.

Facts:

About Polio:

• Polio is an acute infectious disease caused by polio virus.The virus is a human enterovirus of the Picornaviridae.
• It is transmitted from one person to another by oral contact with secretions or faecal material from an infected person.
• It attacks the central nervous system through the bloodstream and damage the cells and paralyse the victim.
• Polio mainly affects children under 5 years of age.There is no cure for polio, it can only be prevented. 
• The strategy to eradicate polio is therefore based on preventing infection by immunizing every child until transmission stops.
• India was declared polio free in 2014 and the last case was reported in January 2011.

Types of Polio virus:

• There are three individual and immunologically distinct wild poliovirus strains namely (a)wild poliovirus type 1(WPV1) (b)wild poliovirus type 2 (WPV2) and (c)wild poliovirus type 3 (WPV3).
• Symptomatically,all three strains are identical, in that they cause irreversible paralysis or even death. 
• But there are genetic and virological differences, which make these three strains three separate viruses that must each be eradicated individually.
• The WPV2 and WPV3 have been eradicated globally but WPV1 remains in circulation in just two countries namely Afghanistan and Pakistan.

Additional information:

About World Polio Day:

• World Polio Day was established by Rotary International on 24th October to celebrate the birth of Jonas Salk who had developed a vaccine against Polio.