Poliomyelitis in Oman. II. Toward eradication.

In the past decade, the Sultanate of Oman has experienced three outbreaks of paralytic poliomyelitis--a widespread polio type 1 epidemic in 1988/1989, four cases of polio type 3 in three different regions in 1991, and a localized type 1 outbreak in 1993. The lessons learnt from each of these epidemics have guided us to modify and improve our polio eradication activities. Currently, these activities include administration of five primary and three booster doses of trivalent oral polio vaccine, yearly national immunization campaigns (NIDs) since 1995 with coverage of >90%, localized immunization campaigns, acute flaccid paralysis (AFP) surveillance which involves reporting of all cases by facsimile to the Department of Surveillance within 24 h of detecting a case and weekly zero reporting from 22 sentinel sites, and virological testing of stool specimens of all AFP cases and their close contacts at the national, World Health Organization accredited laboratory. The cumulative success of these activities has resulted in Oman being free from polio for the past 6 years. However, the possibility of importation of wild poliovirus, particularly from southern and western Asia still exists.