RESUMO
This article presents data of complex study of human granulocytic anaplasmosis the human granulocytic anaplasmosis (HGA) in the western region of Ukraine. Natural HGA foci were identified, where the prevalence of A. phagocytophilum in the main vector (I. ricinus) amount to (12.0 +/- 0.7) %, and seroprevalence of HGA among the healthy population--(28.6 +/- 1.6) %. It's shown that A. phagocytophilum is the etiologic agent of (33.7 +/- 4.9) % of undiagnosed cases of seasonal febrile diseases. Principal characteristics of HGA epidemiology: spring-summer scasonality, the prevalence of disease in the age structure of people of active age (45.30 +/- 1.95 years), a significant level combination with (60.4 +/- 2.2) % Lyme-horreliosis and other tick-borne infections (mixed infections), the different level of activity of HGA epidemic process in forest and steppe geographical landscape zones--were revealed.