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Objective: Vaccine-associated paralytic poliomyelitis (VAPP) is a rare but serious consequence of the administration of oral polio vaccine (OPV). Intensified OPV administration has reduced wild poliovirus transmission in India but VAPP is becoming a matter of concern., Methods: We analysed acute flaccid paralysis (AFP) surveillance data in order to estimate the VAPP risk in this country. VAPP was defined as occurring in AFP cases with onset of paralysis in 1999, residual weakness 60 days after onset, and isolation of vaccine-related poliovirus. Recipient VAPP cases were a subset with onset of paralysis between 4 and 40 days after receipt of OPV., Findings: A total of 181 AFP cases met the case definition. The following estimates of VAPP risk were made: overall risk, 1 case per 4.1 to 4.6 million OPV doses administered; recipient risk,1 case per 12.2 million; first-dose recipient risk, 1 case per 2.8 million; and subsequent-dose recipient risk, 1 case per 13.9 million., Conclusion: On the basis of data from a highly sensitive surveillance system the estimated VAPP risk in India is evidently lower than that in other countries, notwithstanding the administration of multiple OPV doses to children in mass immunization campaigns.

With the launch of the Universal Immunisation Programme in India in 1985, childhood immunisation was provided to children in all districts of the country in a phased manner by 1990. Surveillance for vaccine preventable diseases (VPD) including polio was started at the same time with monthly reporting from the districts to the Ministry of Health and Family Welfare (MOHFW), Government of India (GOI). In 1995, the Pulse Polio Immunisation (PPI) campaign was launched with the objective of polio eradication. Prior to 1997, surveillance for polio was directed at finding clinical polio cases by passive reporting from health facilities. There was no active surveillance for all cases of acute flaccid paralysis (AFP). In 1996, a scheme for the surveillance of AFP was drawn up. With the support of the Danish and US governments and Rotary International, 59 surveillance medical officers (SMOs) were hired, trained, and posted throughout the country in October 1997 to establish active surveillance of AFP. The number of SMOs was increased to 108 in August 1999. The SMOs along with their government counterparts established 10,069 reporting units nationwide by the end of November 1999 reporting weekly the occurrence of AFP cases to the district, state, and national levels; timely case investigation and collection of stool specimens from AFP cases; linkages to support the polio laboratory network; and extensive training of government counterparts. Data reported to the national level is analysed and put on an internet website which is updated every two weeks. Annualised rates of reported non-polio AFP have increased from 0.22 per 100,000 children aged < 15 years in 1997 to 1.57 in 1999. The number of polio cases associated with isolation of wild poliovirus decreased from 1404 in the third trimester of 1998 to 664 in the third trimester of 1999, yet widespread transmission of wild polioviruses persists throughout the country.

Poliomyelitis surveillance in India previously involved the passive reporting of clinically suspected cases. The capacity for detecting the disease was limited because there was no surveillance of acute flaccid paralysis (AFP). In October 1997, 59 specially trained Surveillance Medical Officers were deployed throughout the country to establish active AFP surveillance; 11,533 units were created to report weekly on the occurrence of AFP cases at the district, state and national levels; timely case investigation and the collection of stool specimens from AFP cases was undertaken; linkages were made to support the polio laboratory network; and extensive training of government counterparts of the Surveillance Medical Officers was conducted. Data reported at the national level are analysed and distributed weekly. Annualized rates of non-polio AFP increased from 0.22 per 100,000 children aged under 15 years in 1997 to 1.39 per 100,000 in 1999. The proportion of cases with two adequate stools collected within two weeks of the onset of paralysis increased from 34% in 1997 to 68% in 1999. The number of polio cases associated with the isolation of wild poliovirus decreased from 211 in the first quarter of 1998 to 77 in the first quarter of 1999. Widespread transmission of wild poliovirus types 1 and 3 persists throughout the country; type 2 occurs only in Bihar and Uttar Pradesh. In order to achieve polio eradication in India during 2000, extra national immunization days and house-to-house mopping-up rounds should be organized.

Delhi was the fourth State in India to conduct mass immunization of children (Pulse Polio Immunization) of the < 3 year age group with Oral Polio Vaccine (OPV) as a strategy towards the eradication of poliomyelitis. This study attempted to evaluate the immunization coverage achieved and the channels of communication which were effective in increasing coverage in three high risk areas of Delhi during October 1994. The overall immunization coverage was 89%. Information sources like enumeration visits, posters, television, radio and schools statistically correlated with the Pulse Polio Immunization (PPI) outcome. However, the cost of enumeration was high. Other less expensive channels of communication appeared to be equally effective. Only 11% of the children surveyed were not immunized with PPI OPV. The major reasons why some children did not receive OPV was that parents were "not informed" or they were "too busy".