Diversity and Distribution of Bacterial and Parasitic Tick-Borne Pathogens in Armenia, Transcaucasia

Sargis A.  Aghayan; Gohar  Grigoryan; Hasmik  Gevorgyan; Tehmine  Harutyunyan; Martin  Rukhkyan; Vahagn  Muradyan; Gregory  Karadjian; Maud  Marsot; Sara  Moutailler; Thomas  Pollet

doi:10.18502/ijph.v53i11.16960

Sargis A. Aghayan Laboratory of Molecular Parasitology, Scientific Center of Zoology and Hydroecology of the National Academy of Sciences of Armenia, Yerevan, Armenia
Gohar Grigoryan Laboratory of Molecular Parasitology, Scientific Center of Zoology and Hydroecology of the National Academy of Sciences of Armenia, Yerevan, Armenia
Hasmik Gevorgyan Laboratory of Molecular Parasitology, Scientific Center of Zoology and Hydroecology of the National Academy of Sciences of Armenia, Yerevan, Armenia
Tehmine Harutyunyan Chair of Zoology, Yerevan State University, Yerevan, Armenia
Martin Rukhkyan Laboratory of General Helminthology and Parasitology, Scientific Center of Zoology and Hydroecology of the National Academy of Sciences of Armenia, Yerevan, Armenia
Vahagn Muradyan Center for Ecological-Noosphere Studies, National Academy of Sciences, Yerevan, Armenia
Gregory Karadjian UMR BIPAR, INRAE, Anses, Ecole Nationale Vétérinaire d’Alfort, Laboratory of Animal Health, Maisons-Alfort Cedex, France
Maud Marsot Unité EPI, Animal Health Laboratory, INRA, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
Sara Moutailler UMR BIPAR, INRAE, Anses, Ecole Nationale Vétérinaire d’Alfort, Laboratory of Animal Health, Maisons-Alfort Cedex, France
Thomas Pollet UMR BIPAR, INRAE, Anses, Ecole Nationale Vétérinaire d’Alfort, Laboratory of Animal Health, Maisons-Alfort Cedex, France

DOI: https://doi.org/10.18502/ijph.v53i11.16960

Keywords: Tick-borne pathogen; Bacterial pathogen; Special variation; Parasite ecology; Armenia

Abstract

Background: Variations in the distribution and prevalence of pathogens in ticks can have significant consequences for human health. Information on these variables in Transcaucasia is scarce, so the aim of our study was to conduct a large-scale study to detect selected tick-borne infectious agents in Armenia.

Methods: Overall, 209 adult ticks were collected from different hosts including 4 samples from human clothes. We tested ticks using high-throughput microfluidic single-cell real-time PCR to detect 42 genospecies of pathogens. We used GIS to determine biotic and abiotic factors governing the prevalence of pathogens and applied statistical analyses to test the association between prevalence of pathogens depending on hosts, locality and environment.

Results: From 209 samples, 134 were positive to targeted pathogens. Anaplasma phagocytophilum Foggie, 1949 was the most prevalent case (44%). The highest overall prevalence was observed in ticks from sheep (74%), followed by cows (67%) and calves (60%). The highest multiple infection rates were also detected in sheep (40%) and calves (40%) followed by cows (28%). One statistically significant association was found among co-infections (P<0.05). The prevalence of pathogens varied according to locality. The abundance of Anaplasma spp. is significantly correlated with “slope” and “vegetation” factors. Similar patterns were detected for other pathogens.

Conclusion: This was the first large-scale survey of multiple tick-borne pathogens in Armenia and Transcaucasia. The results of this study shed light on spatial variations in pathogen infection rate among adult ticks found on hosts and underline a number of environmental determinants of pathogen distribution among ticks.