Journal of School of Public Health and

Background and Aim: Iran managed to eradicate the wild poliovirus in 2000. However, a large number of AFP cases are still detected each year because of close surveillance: there were 450 reported AFP cases in 1382. The expected number of cases for the year 1382 in the province of West Azarbayjan (with an under-15 population of 1100000) was 11, while the observed number was more than 6 times greater (70 cases). In this study we investigated the non-polio enteroviral agent which could cause the AFP cases especially in Azarbayjan Province. Hence, the main purpose of the study was to identify circulating non-polio enteroviruses, using cell lines RD, Hep2, L20 and RT-PCR.

Material and Methods: All stool specimens of AFP cases were treated with chloroform and then injected into the above-mentioned cell lines. The isolated viruses were identified by the NT method. In cases where polioviruses were isolated, intratypic differentiation (wild vs. vaccine strains) using hybridization and ELISA tests. Finally, we performed RT-PCR with pan-EV primers on all samples.

Results: Using cell cultures, we were able to isolate 10 viruses, 9 of which were isolated by the RD cell line and this is regarded as the most sensitive cell line. The RT-PCR also identified 16 different viruses, 7 of which were not isolated on the RD line. Thus, RT-PCR could increase viral detection by 10%, indicating a high degree of high sensitivity.

Conclusion: Although the combination of cell culture and RT-PCR for detection and identification of non-polio enteroviruses causing AFP is invaluable, more than 75% of AFP patients were enterovirus negative. Therefore, they must be checked for other agents such as flavivirus (viral) and Campylobacter jejuni (bacterial).