While the Central Government is planning to reintroduce the old monovalent oral polio vaccine (mOPV) instead of trivalent oral polio vaccine (tOPV) in the national polio eradication drive and to conduct monthly rounds of vaccination in most affected areas, many experts are questioning the very effectiveness of spending several million of rupees for the programmme.
The Polio Eradication Initiative launched in India in 1995, as part of the Global Polio Eradication Initiative (GPEI), had promised to eradicate the disease from India by 2005. The target was postponed to 2004-07, and now the Government has set a target to eradicate the disease within the next four years.
Jan Swasthya Abhiyan, a grouping various health NGOs have already started a propaganda against the drive citing the Programme's ineffectiveness in a vast country like India. They note that while adequate immunization coverage is vital, the National Family Health Survey, 3rd Round 2005-06, Maharashtra, reports that the percentage of fully immunized children dropped from 78.4 per cent in 1998-99 to 58.8 per cent in 2005-06. In rural areas this fall was from 77 per cent to 50 per cent, while in urban areas it was from 81 per cent to 68 per cent.
Some of the experts say that Pulse Polio Strategy is a cost-disaster and is epidemiologically unsound. (India has earmarked $210 million for the polio drive activities for 2006-07). The NGOs cite that more than Rs 2500 crores have already been spent on this misadventure and more than Rs 400 crore/year was allocated during the Tenth plan period.
Dissecting the case history in India in recent years, they note that case-control epidemiological study of the outbreak of the disease in 1999 in Uttar Pradesh, by CDC, Atlanta, USA, revealed that majority (89%) of these affected children had received more than 3 doses of OPV, same as for the children in matched control group. Of 1,126 virologically confirmed cases of polio reported in 1999, 64 per cent were due to P3 virus, which is known to have lower immunogenicity. While the median age at paralytic onset was 16 to 18 months, children up to the age of 14 years were involved. This indicates that immunity weans and older children become susceptible to polio. An important finding was that a significant number of affected children had at least one injection in the month prior to the onset of paralysis.
In March 2006, two wild poliovirus strains were isolated from sewage from Dharavi, Wadala and Shivajinager (Chembur). Despite several rounds under 'Pulse Polio' and polio-free status for 32 months, a four-year old girl, from Beed District, Maharashtra, suffered from paralytic polio in August 2006. Diagnosis was confirmed.
Wild poliovirus was isolated from nine-year-old girl from Govandi, Mumbai, in Sept. 06. The girl had earlier received 12 doses of polio vaccine under pulse polio programme. Another case, 11-month-old boy from the same area, was confirmed on 9th October 2006. The boy has received more than four doses of oral polio vaccine. Occurrence of provocative poliomyelitis of big magnitude in UP is a good evidence of existence of thousands of children and others in the community who were infected with poliovirus. This was despite efforts of 10 National Immunization Days and one High Risk Area Immunization Programme in the past. Outbreaks in Beed and Mumbai, and isolations of wild virus in Mumbai sewage, confirms that immunization person cannot eradicate polio virus infection, notes an expert Dr N S Deodhar from Pune, in a presentation on "Poliomyelitis Eradication- Challenging Task and Pulse-Polio Programme Can Never Do It"
Even with more than three doses of OPV, many children are not fully protected and will not prevent non-polio paralytic and vaccine induced polio cases. While, vaccination coverage under pulse polio is for children below six year of age, the truth is that children above this age is also susceptible. With inadequate coverage of less than 98 per cent under pulse polio and 30 to 60 per cent under regular immunization programme, natural history of polio infection is not affected adversely and fails to serve purpose of the goal of eradication.
They also cite that the number of cases of poliomyelitis was reduced from 24,257 in 1988 to 4,703 in 1994. The reduction in cases was 80 per cent and we were on the right path. Many countries have now reached zero polio case status only with routine immunization and without 'Pulse Polio' gimmick. A Report of the National Commission on Macroeconomics and Health, Equitable Development, Health Future, MH&FW, GOI, August 2005 had noted that before the benefits of Expanded Programme for Immunization EPI could be realized, Pulse Polio Initiative was launched in the country, they observe.
Instead of the massive eradication drive, it is best to strengthen the routine immunization. Further, doctors need to be educated on the danger of giving injection to children during polio season. The basic requirement is to improve and strengthen public health system and environmental health to eradicate the disease than conducting massive vaccination exercises, they recommend.