Diversity of hard tick populations and their geographic variations in northwestern Iran

Abstract Ticks are forced vertebrate ectoparasites, including humans, and are vectors of serious diseases such as Crimean Congo Hemorrhagic Fever, Relapsing Fever, and various forms of encephalitis. Spatial assessment of the prevalence of ticks and detection of high risk areas for tick-borne disease transmission and evaluation of ecological measures are key aims of this research. Ticks were collected using standard methods From 27 villages in the region of Sarab County in north-eastern Iran during the four seasons of 2018-219 and identified using valid keys. The calculation of indices for biodiversity were based on the Margalf index, Shannon-Weiner index and Simpson index. R2.15 Statistical software was used for statistical analysis of indices of biodiversity, and ArcMap10.4.1 software and IDW and GeneralG methods and analysis were used to investigate spatial dispersion and to determine important tick hotspots. Thirty-five percent of the 2,500 animals surveyed were infected. A total of 1416 ticks were caught, 74.6 % were adult ticks, % were nymph and 1.4 percent were larvae. Ninety four percent of the ticks caught belonged to hard ticks relating to 4 genera and 6 percent to soft ticks relating to 2 genera. The highest species biodiversity was related to summer (1.4234), and the lowest was related to winter (0.7379), according to the Margalef diversity index. In the central part of the study region a large hotspot area was found. The area of study was very prone to tick-borne disease transmission in terms of tick diversity and tick species richness, and it was important to inform people to monitor to avoid diseases. Keywords: Ticks, Species biodiversity, GIS, Iran