Surveillance : Acute flaccid paralysis

Under the polio eradication initiative, every case of acute flaccid paralysis (AFP), including Guillain-Barre Syndrome, in patients under 15 should be reported immediately to the regional health authorities and the Ministry of Health. These AFP cases will be handled as suspected cases of polio until proven otherwise. Stool specimens should be collected and submitted for virus isolation and a serum sample taken for serology. Reporting of every case of AFP will ensure investigation of all possible polio cases. The eradication effort depends on AFP surveillance data as a basis for actions taken, as an assessment of progress toward the eradication of poliomyelitis, as identification of high-risk areas and as a guide for immunization strategies. Immediate actions triggered by an AFP report target immunization activities at the catchment area of the case, where all children under 5 should receive two doses of oral polio vaccine (OPV) regardless of their previous immunization state. Because the eradication initiative depends on finding every case of polio, it is better to report AFP that is not polio than to risk missing a case that could be polio.

A consistent demonstrable downward trend of poliomyelitis has been seen in the Kingdom between 1977 and 1994, and very low levels have been sustained in the last seven years. However, from 1989 to 1992, low numbers of reported AFP indicated that the surveillance system required improved sensitivity. Accordingly, several new activities were introduced in 1993 to strengthen AFP surveillance. During 1993, AFP reports increased to 43, 10 times more than 1992, using an expected AFP baseline rate of 1/100,000. About 72% of the expected numbers of cases were reported. Continuous improvement has been noted during the first nine months of 1994, during which 58 cases were reported (80% of the expected figure).

The most important activities introduced in the last two years are:

The table on the previous page shows the results of close monitoring of AFP surveillance performance indicators. The data indicate that the polio surveillance system in the Kingdom is functioning properly, though more effort is needed to notify cases within 24 hours and to initiate control measures within 48 hours.