Cross-Sectional Study on the Prevalence and Factors Influencing Occurrence of Tick-Borne Encephalitis in Horses in Lithuania
Arnoldas Pautienius,
Austeja Armonaite,
Evelina Simkute,
Ruta Zagrabskaite,
Jurate Buitkuviene,
Russell Alpizar-Jara,
Juozas Grigas,
Indre Zakiene,
Dainius Zienius,
Algirdas Salomskas,
Arunas Stankevicius
Affiliations
Arnoldas Pautienius
Virology Laboratory, Institute of Microbiology and Virology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Austeja Armonaite
Laboratory of Immunology, Department of Anatomy and Physiology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Evelina Simkute
Laboratory of Immunology, Department of Anatomy and Physiology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Ruta Zagrabskaite
National Food and Veterinary Risk Assessment Institute, J. Kairiukscio Str. 10, LT-08409 Vilnius, Lithuania
Jurate Buitkuviene
National Food and Veterinary Risk Assessment Institute, J. Kairiukscio Str. 10, LT-08409 Vilnius, Lithuania
Russell Alpizar-Jara
Research Center in Mathematics and Applications (CIMA-UE), Institute for Advanced Studies and Research, Department of Mathematics, School of Science and Technology, University of Évora, Rua Romão Ramalho 59, 7000-671 Évora, Portugal
Juozas Grigas
Virology Laboratory, Institute of Microbiology and Virology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Indre Zakiene
Laboratory of Immunology, Department of Anatomy and Physiology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Dainius Zienius
Department of Veterinary Pathobiology, Faculty of Veterinary Medicine Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Algirdas Salomskas
Department of Veterinary Pathobiology, Faculty of Veterinary Medicine Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Arunas Stankevicius
Laboratory of Immunology, Department of Anatomy and Physiology, Faculty of Veterinary Medicine, Lithuanian University of Health Sciences, Tilzes str. 18, LT-47181 Kaunas, Lithuania
Various animal species have been evaluated in depth for their potential as Tick-borne encephalitis virus (TBEV) sentinel species, although evidence for equine capacity is incomplete. Therefore, a comprehensive cross-sectional stratified serosurvey and PCR analysis of selected horses (n = 301) were performed in TBEV endemic localities in Lithuania. Attached and moving ticks (n = 241) have been collected from aforementioned hosts to evaluate natural infectivity of TBEV vectors (Ixodes spp.) in the recreational environments surrounding equestrian centers. All samples were screened for TBEV IgG and positive samples were confirmed by virus neutralization test (VNT). 113 (37.5%) horses from all counties of Lithuania tested positive for TBEV IgG, revealing age and sex indifferent results of equine seroprevalence that were significantly dependent on pedigree: horses of mixed breed were more susceptible to infection possibly due to their management practices. TBEV prevalence in equine species corresponded to TBEV-confirmed human cases in the precedent year. As much as 3.9% of horses were viraemic with TBEV-RNA with subsequent confirmation of TBEV European subtype. 4/38 of tested tick pools were positive for TBEV-RNA (Minimal infectious rate 1.2%). Several unknown microfoci were revealed during the study indicating areas of extreme risk close to popular human entertainment sites. The study provides important evidence in favor of horses’ usage as sentinel species, as equines could provide more detailed epidemiological mapping of TBEV, as well as more efficient collection of ticks for surveillance studies.
