Monitoring of vector-borne diseases in the west part of Ukraine

Abstract

During recent years, infectious and invasive animal diseases caused by viruses, bacteria, and protozoa and transmitted by ticks have been a new problem in medical and veterinary practice. Many of these diseases are zoonoses and lead to the disability and mortality of humans and animals. Ixodes ricinus and Dermacentor reticulatus are species of ticks that are commonly attack animals and humans in Europe. These ticks are spread throughout the EU and are involved in the transmission of a large number of vector-borne diseases. To date, relatively limited data on the circulation of tick-borne diseases and their transmission in western Ukraine are presented. The purpose of this study was to monitor the types of ixodid ticks, as well as to identify pathogens in ticks collected from the environment in urban parks and from dogs and cats. A total of 215 ticks (22 Ixodes ricinus and 193 Dermacentor reticulatus) collected in two regions of Lviv and Ivano-Frankivsk were investigated. Pathogens, namely, Rikettsia spp., Candidatus Neoehrlichia mikurensis, Anaplasma phagocytophilum and Bartonella spp., were detected in 64.0% of the I. ricinus ticks. Overall, 18.2% of I. ricinus ticks were positive for Rikettsia spp., 54.5% for Candidatus Neoehrlichia mikurensis, 9.1% for A. phagocytophilum and Bartonella spp. confirmed in 4.5% of the studied ticks. Mixed infestations were found in 5 samples of I. ricinus DNA, representing 22.7%. In addition, 74.6% of D. reticulatus ticks were infested with these pathogens. Overall, 30.0% of D. reticulatus ticks were positive for Rikettsia spp., Candidatus Neoehrlichia mikurensis was confirmed in 54.9%, A. phagocytophilum in 1.6%, and Bartonella spp. in 6.2% of the studied ticks. Mixed infestations were found in 35 D. reticulatus DNA samples, representing 18.1%. The prevalence of Rikettsia spp. in two regions of Lviv and Ivano-Frankivsk, among the studied ticks was 28.8%, Bartonella spp. – 6.0%, A. phagocytophilum – 2.3%, Candidatus Neoehrlichia mikurensis – 54.9%. Our data indicate the presence of pathogens in urban populations of ticks of I. ricinus and D. reticulatus in west part of Ukraine. Monitoring of tick-borne diseases is an important tool in the prevention and control of infections transmitted to humans and animals.