Background: Medical geography deals with the application of major concepts and theories derived from human and physical geography to issues of health and disease. Between1970-1980, Russian scientists were first figured landscape, geographical distribution of TBE in Mongolia. Since human cases of TBD were registered from 2005, around 2000 cases of TBD were registered. From 15% of diseases and 78% of fatal cases were tick-borne encephalitis. Therefore, were tried to create current geographical distribution of TBE in Mongolia and detect risk areas. Мaterials and Methods: 287 TBE cases data, information of TBE positive tick and human data were analyzed which registered in NCZD between 2005-2017. Arc GIS 9 were used for create map. Mongolian map was divided by 5 landscape range such as forest-taiga, forest-steppe, steppe, steppe-desert, gobi and high mountain. Result: In forest-taiga range, 57% of TBE cases and incidence was 9.51 per 10000 population. 56.4% of I.persulcatus tick, 1.9% of D.nuttalli tick were found and infection rate of tick was Ixodes persulcatus-6.97%, Dermacentor nuttalli-5.2%. Seroprevalence of TBE was 25±12.1 among population.
In forest-steppe range, 40% of TBE cases and incidence was 0.56 per 10000 population. 43.6% of I.persulcatus tick, 44.3% of D.nuttalli, 24.4% of D.silvarum tick tick were found and infection rate of tick was Ixodes persulcatus-3.08%, D.silvarum-1.56% and D.nuttalli-1.56%. Seroprevalence of TBE was 14.5±11 among population.
In steppe range, 0.7% of TBE cases and incidence was 0.12 per 10000 population. 62.2% of D.silvarum tick, 23.9% of D.nuttalli tick were found and infection rate of tick was D.nuttalli-2.81% and D.silvarum-1.2%. Seroprevalence of TBE was 16.3±6.5 among population.
In other range including steppe-desert, gobi and high mountain, 2.8% of TBE cases and incidence was 0.1-0.27 per 10000 population. 62.2% of D.silvarum tick, 47.6% of D.nuttalli tick were found and infection rate of tick was D.nuttalli-0.84%. Seroprevalence of TBE was 2.5-13.1 among population. Conclusion Natural foci of tick-borne encephalitis have been registered in all landscape ranges of Mongolia and higher risk area of those ranges were forest-taiga and forest-steppe. Dermacentor silvarum, Dermacentor nuttalli tick becoming dominant vector of TBE in steppe range.