Iran, by Restriction Endonuclease Analysis(REA)

Leptospirisis is an important zoonosis disease with the most widespread prevalence in tropical and semitropical regions. It is also very common in flat areas of Guilan province (northern Iran). Pathogenic leptospires excreted from carrier animals can survive in surface waters and humid soil along with nonpathogenic serovars for a long time.A limited number of serovars are usually common in any endemic region and whose characterization is helpful in revealing epidemiological features of the disease and detecting the source(s). This study has been planed to isolate and identify the common leptospira strains from surface waters of central regions of the flat areas of Guilan province.Matrial& Sampling from surface waters of the area was done from May to late September 2006. Each sample was inocculated in EMJH medium. DNA extraction was performed for all the positive cultures by the standard method and REA was done for DNA of each strain using EcoRI. Each band profile was compared and analysed by band profile of standard strains. 168 samples of all the 301ones were positive in the first round of culturing, but only 33 samples showed high rate bacterial numbers in the following culturing stage, so were in good position to perform ERA. Band profiles of only 27 isolates were comparable and similar to some pathogenic (Interrogans, Kirchnery, and Borgpetersenii), and saprophytic (Biflexa, and Wolbachia) species belong to pathogenic serogroups: Icterohaemorrahgia, Pomona, Ballum, Hardjo, kanicola, and grippotyphosa, and finally nonpathogenic serogroups: Andamana,Patoc, and semaranga.Discussion&Conclussion: Our study showed that pathogenic serovars are more common in rice paddies, because of the long time stop of water and high trafficking rate of domestic and wild animals and rodents. Saprophytic serovars were more common in rivers and irrigation canals.