Species identification and pathogen detection by FLUIDIGM, a high-throughput PCR technique in ticks collected from northern Sweden

• Main Author: Choklikitumnuey, Phimphanit
• Format: Other/Unknown Material
• Language: English
• Published: SLU/Dept. of Biomedical Sciences and Veterinary Public Health 2020
• Subjects: ticks; tick-borne diseases; fluidigm; Northern Sweden
• Online Access: https://stud.epsilon.slu.se/15820/

Due to the environmental climate changes, northern Sweden is potentially a geographical area where new tick species could become established and introduce along with them new tick-borne pathogens. High-throughput real-time PCR, FLUIDIGM, was selected to perform the pathogen detection in this study. In this study ticks (n=1,421) from northern Sweden in 2018 (between June and October), either collected from different host species (dog, cat, horse, rabbit, cattle, mice, rabbit and human) or questing ticks collected from the environment, were identified at species level using morphological keys; Ixodes ricinus/I. persulcatus identification was confirmed by a PCR assay included within FLUIDIGM analyses. The ticks were identified belonging to the species as follow: 1,381 Ixodes ricinus ticks (adult females; n=1167, adult males; n=176 and nymphs; n=38), 27 Ixodes persulcatus ticks (adult females; n=21, adult males; n=5 and nymphs; n=1), 4 most likely hybrid species of Ixodes ricinus and Ixodes persulcatus (adult females; n=4), 12 Ixodes trianguliceps (adult females; n=11 and nymphs; n=1) and 1 adult female Hyalomma marginatum. Ticks were positive for the following tick-borne pathogens: 25.26% Borrelia spp., 4.08% Babesia venatorum, 0.28% B. microti,B. divergens/B. capreoli., 9.15% Anaplasma spp., 9.22% Anaplasma phagocytophilum, 6.19% Neoehrlichia mikurensis, 25.62% Rickettsia helvetica, 0.07%, Rickettsia aeschlimannii, 0.49%, tickborne encephalitis virus (TBEV), 2.25% Uukuniemi virus (UUKV), 4.08% Babesia venatorum, 0.28% Babesia microti, and 0.49% Babesia divergens/B. capreoli. This is the first time that this form of study on ticks and tick-borne pathogens has been performed in this northern area of Sweden. The results confirm that I. ricinus is the dominant tick species in this area and the increased spreading of I. persulcatus compared to previous reports should be observed. These results confirm that even ticks in this northern are can also be vectors of important medical and veterinary pathogens. Moreover, this ...