Browsing by Subject "Nairoviridae"

Tick-borne diseases pose a major One Health threat in Finland. Tick-borne pathogens are transmitted through a tick-bite, impacting human, companion animal, livestock, and wildlife health. The geographical distributions of many tick species are shifting as a result of climate change. In northern Europe, tick distributions are expanding northward due to previously inhospitable climates becoming warmer. This has led to enhanced contact between ticks, humans and companion animals – increasing the incidence of tick-borne disease transmission. Established tick-borne pathogens such as TBEV and Borrelia spp. are considered endemic across Finland. However, the diversity of viruses found within ticks in Finland remains largely unexplored. Thus, here we aimed to characterize the viromes of the dominant tick species found in Finland. We used Next-generation sequencing methods to characterize the viral components of Ixodes Ricinus and Ixodes persulcatus ticks associated with companion dogs across Finland. In total, 4 different pools consisting of 36 ticks were sequenced. Our results identified 9 unique viruses belonging to the families Nairoviridae, Phenuiviridae, Iflaviridae and Partitiviridae. We identified numerous recently characterized nairo-like viruses, including Pustyn virus and Gakugsa tick virus. We were able to bridge the gap on the geographical spread of many of these viruses, including reporting Sulina virus and Norway nairovirus 1 for the first time after their discovery. Phylogenetic analyses revealed close relationships between the recently characterized RNA viruses, and a high degree of conservation across wide geographical ranges. As previously highlighted, the pathogenicity of these newly identified viruses is not yet established. However, our results indicate many of the viruses identified are closely related to viruses associated with acute febrile illness in humans. Due to our small sample size, we are unable to imply the virome composition for all ticks in Finland. However, we highlight a high degree of viral diversity even within a small sample size of ticks. Further research is urgently required to establish whether these recently characterised viruses pose a threat to human or animal health in Finland.