Vol. 48 / No. 46 Poliomyelitis Eradication — Continued
EMR Laboratory Network
The EMR laboratory network comprises 12 laboratories (eight national and four regional reference laboratories). During 1998, all network laboratories except those in Iraq and Sudan were accredited by WHO. On the basis of their improved performance, the laboratories in Iraq and Sudan received provisional accreditation in 1999. As of October 1999, 3445 stool specimens from 1800 (99%) of 1824 persons with AFP re- ported from 22 EMR countries underwent laboratory investigation in a WHO network laboratory. Laboratory results were reported on time (within 28 days of receipt of specimen) for 80% of stool specimens. The regional average nonpolio enterovirus iso- lation rate (an indicator of the adequacy of laboratory technique and specimen han- dling) was 9%; 93% of the specimens were received in the laboratory in good condition. Genetic sequence analyses are performed routinely on all wild poliovirus isolates in the region. The information has provided evidence of progress toward eradication through identifying virus reservoirs, establishing virus transmission links and cross-border importations, and detecting laboratory contamination (5 ).
Incidence of Polio
From 1988 through October 1999, the number of confirmed polio cases reported in the EMR decreased 81%, from 2342 to 446. Of 23 EMR countries, 15 reported zero cases during 1999. Since 1996, five countries (Afghanistan, Egypt, Iraq, Pakistan, and Sudan) have reported cases with indigenous strains of wild poliovirus. The last vi- rologically confirmed case of polio in Egypt had onset in March 1999. Wild poliovirus has not been isolated in Somalia through a functioning surveillance system in the north or from AFP cases reported in Yemen during 1998 and 1999. During 1998 and 1999, Pakistan continued to report the largest number of cases and contributed nearly 60% of the total number of cases in the region. Wild poliovirus type 2 has not been isolated in EMR since 1997 (Figure 2).
FIGURE 2. Isolation of poliovirus serotypes from acute flaccid paralysis cases — Eastern Mediterranean Region, 1999
Afghanistan P1, P3
Egypt P1, P3
Pakistan P1, P3
P1 = Poliovirus Type 1 P2 = Poliovirus Type 2 P3 = Poliovirus Type 3
? = No Isolates Reported But Virus Likely
Sudan P1, P3
No Wild Virus