In 2003 patients of tsutsugamushi disease were found in 24 provinces of North and North-Central. Purpose: To determine species composition of rats, chiggers and O tsutsugamushi in the study sites. Method: Cross-section survey, O tsutsugamushi antibodies in serotypes of rats detected by rapid diagnostic biological (BioLine SD - South Korea). Results: Four species of rat have been collected including: Rattus explants, R rattus, R (Berylmus) bowersi and Bandicota savilei; four rat-parasite chiggers including: A.