Polio Eradication and Acute Flaccid Paralysis Surveillance

Objective: To review the impact of high non-Polio Acute Flaccid Paralysis (AFP) rate on Polio eradication. Background: AFP surveillance is an essential strategy for achieving Polio eradication. Recently Advisory Committee for Polio Eradication (ACPE) doubled the operational target for non-Polio AFP to 2 to improve the sensitivity of AFP surveillance. Presence of compatible Polio represents weakness in surveillance. This study reviews the impact of high non-Polio AFP rate on Polio eradication. Material and Methods: Published AFP surveillance data of India of 2006 and 2007. Findings: The highest non-Polio AFP rate in India is seen in the polio hyper endemic state of Bihar. In 2006 the rate was 19 with an adequate stool rate of 82%. A total of 189 cases of Polio were reported from Bihar that year of which only 61 were confirmed. That means only 32% of Polio cases could be confirmed instead of 82% going by the adequate stool collection rate. In 2007 only 52% (22/42) of Polio cases could be confirmed even though adequate stool collection rate is 87% and non-Polio AFP rate 19.26 (as on 8th September 2007). Similar findings are found in the other hyper endemic state of Uttar Pradesh and Nationally though of lesser degree. Very high non-Polio AFP rate should have resulted in a marked increase in the proportion of Polio cases confirmed as the true indication of enhanced surveillance sensitivity, which did not happen in India. Conclusion: Very high non-Polio AFP rate did not really increase the sensitivity of AFP surveillance in India as shown by the large proportion of compatible cases and could be potentially harmful for Polio eradication by masking the true rate of confirmation of Polio cases. There is a need to review AFP surveillance in those areas with very high non-Polio AFP rate.