Characteristics of Acute Flaccid Paralysis Reported by the Surveillance System and Verified by WHO Officer in Akwa Ibom State-Nigeria, 2006-2012

Abstract

Background: Acute Flaccid Paralysis (AFP) was adopted by World Health Organization (WHO) in 1988 as a key pillar used in monitoring progress towards the global polio eradication initiative. High quality AFP surveillance is essential to support this global initiative. We applied recently developed case verification methods for the quantitative evaluation of AFP cases reported to the surveillance systems to evaluate the quality of AFP reports in Akwa Ibom State, Nigeria. Objectives: The aim of this study is to identify the demographic, clinical and epidemiological attributes and quality of acute flaccid paralysis surveillance. Methods: All AFP cases reported in children 0 - 14 years during January 2006 to December 2012 were investigated and verified by WHO surveillance officers, using standard questionnaire. Two stool samples 24 - 48 hours apart from a total of 1184 AFP cases were collected within 14 days of onset of paralysis with the prior oral/verbal informed consent and transported to the national polio laboratory under reverse cold chain. Result: In all, 885/1184 representing 75% of the AFP cases reported were verified by WHO officers in the period under review. Overall, 534/885 (60.3%) of AFP cases had more than >3 doses of Oral Polio Vaccine (OPV), while 196/885 (22.2%) received 3 dose of OPV and 128/885 (14.5%) received between 1 - 2 doses of OPV. It was interesting that 27/885 (3%) never received OPV before. Overall, 743/885 (84.0%) were reported within ≤14 days of paralysis onset, while 142/885 (16%) were reported after ≥14 days of paralysis onset. In total, 797/885 (90.1%) of cases were found to have fever at the onset of paralysis; paralysis was found to be asymmetric in 805/885 (91%). Wasting or diminished muscle tone was observed in 34.0% of cases verified, while deep tendon reflexes were good (normal) in 79% of cases. Gullain-Barre syndrome was observed in 50.9% of the reported cases followed by injection neuritis (25.0%) and transverse myelitis (2.0%). However, other causes recorded 22.1%. The legs (90.2%) are the parts of the body mostly affected, while arm recorded 9.8% of the AFP cases reported and verified. Conclusions: The result of this study indicates that the characterization of AFP cases reported to the surveillance network could provide better understanding of age, and sex distribution, common clinical causes of AFP and impact of distance to health facilities on the health seeking behaviours of AFP cases.