Environmental surveillance of non-polio enteroviruses in Iran

Background: Enteroviruses can shed in feces for several weeks, so many excrete viruses can remain infectious for a long time in environment. Therefore, by detecting enteroviruses in environmental specimens and sewage, we can understand this virus circulation, the approximate ratio of contaminated persons in society and they are suitable indicators for environmental surveillance. Methods: Since March 2006 to February 2007, 86 specimens from Sistan & Balouchestan, 63 specimens from Tehran and 48 samples from Fars sewage disposal systems and surface water were collected by Grab Sample method and tested for enteroviruses directly by using two concentration methods: Pellet and Two-phase. Then Non-Polio Enteroviruses (NPEV) were serotyped by microneutralization method. Results: Enteroviruses were isolated from 49(56.98%) of specimens in Sistan & Baluchestan, 38(60.32%) in Tehran and 11(22.92%) in Fars. Besides, the majority of Non-Polio Enteroviruses related to Non-typable Enteroviruses (N. T. E. V), E11 (31.52%), COX-B (27.58%), E7 (17.73%) and E4 (21.67%). Conclusion: Environmental surveillance has been used successfully in monitoring enteric virus circulation and assessing the extent or duration of epidemic non polioviruses in specific populations. The results of this research show the seasonal circulation of enteroviruses in different parts of Iran.