Hyderabad: On Tuesday, the Telangana government called for a unique polio vaccination drive in Hyderabad, as part of preventive action after a observation study supervised by the World Health Organisation found traces of vaccine-derived polio virus in the urban area of Amberpet nala, a major sewage passage in the city.
Poliomyelitis
Poliomyelitis (polio) is a highly infectious disease caused by a virus. It spreads through the nervous system thereby causing paralysis, medically called an acute flaccid paralysis (AFP), which is marked by abrupt muscle weakness and pain in the limbs. The disease is transmitted from person to person, mostly via the faecal-oral route, affecting kids under five years of age. In the absence of wild polio virus (WPV) transmission, India was confirmed as a polio-free country in March 2014, after years of persistent vaccination.
Disclosure About The Hyderabad Rsearch
World Health Organisation conducts surveillance for cases of AFP and gathers samples of sewage water to find any traces of polio viruses. This is for the preservation of poliomyelitis elimination in polio-free countries. In April with the study in Hyderabad, out of 30 samples gathered, a sample from Amberpet nala contained traces of type-2 VDPV. Lab tests have revealed that the virus has passed via human body and has gone through mutation or nucleotide change. Similar virus strains were detected in Gujarat, Bihar and Delhi. The Telangana government asked people not to fear, and called for a one-week polio vaccination drive in Hyderabad, beginning from 20 June, to vaccinate about 300,000 children.
Vaccine-Derived Polio Virus?
The source of the virus is the vaccine itself. The oral polio vaccine called polio drops, which India established greatly to fight against polio, contain a live, attenuated or weakened polio virus. When a child is vaccinated, the weakened vaccine-virus duplicates in the intestine and enters into the bloodstream, triggering a defensive immune response in the child. The child discharges the vaccine-virus for a period of 6 to 8 weeks as in wild poliovirus. Significantly, as it is voided, some of the vaccine-virus may not be the same any more as the original vaccine-virus as it gets genetically changed throughout replication. In areas of inadequate sanitation, this excreted vaccine-virus can spread rapidly in the community and spread disease to children with low immunity.
The menace About VDPV
The cases of debilitation and paralysis caused by VDPV are scarce as the virus has to circulate for a long time in the community of under-immunised population before it can spread disease and cause paralysis in someone. Vaccine-associated paralytic poliomyelitis (VAPP) takes place in an estimated 1 in 2.7 million children getting their first dose of oral polio vaccine, according to a public-private union of national governments, the Global Polio Eradication Initiative (GPEI) and World Health Organisation(WHO).
Meanwhile, the aspect that is a serious issue is that India reports high number of non-polio acute flaccid paralysis or paralytic cases in kids who are below 15 years of age, which the study connects to the VDPV. At least 50,000 acute flaccid paralysis cases are examined in India annually as a part of its surveillance system according to world health organization.
Inactivated Polio Vaccine and Oral Polio Vaccine
The recognition of VDPV in Hyderabad and other places has strengthened the debate on replacing oral polio vaccine (OPV) with inactivated polio vaccine (IPV). IPV given via an injection contains inactivated virus, thought about to be safer than OPV that contains live virus. World Health Organisation has been recommending IPV over OPV as part of its worldwide master plan on polio eradication. On December 1, India introduced IPV in the compulsory immunization programme 6 states.IPV will be given in addition to the existing OPV for now. OPV has its strong supporters that believe that the vaccine is best suited for countries like India due to its low cost, high benefit and ease of administering, and insist that the safety concerns are exaggerated compared to the benefits of the vaccine.