Emerging Tick-Borne Viruses in the Twenty-First Century

Abstract

Ticks, as a group, are second only to mosquitoes as vectors of pathogens to humans and are the primary vector for pathogens of livestock, companion animals, and wildlife. The role of ticks in the transmission of viruses has been known for over 100 years and yet new pathogenic viruses are still being detected and known viruses are continually spreading to new geographic locations. Partly as a result of their novelty, tick-virus interactions are at an early stage in understanding. For some viruses, even the principal tick-vector is not known. It is likely that tick-borne viruses will continue to emerge and challenge public and veterinary health long into the twenty-first century. However, studies focusing on tick saliva, a critical component of tick feeding, virus transmission, and a target for control of ticks and tick-borne diseases, point toward solutions to emerging viruses. The aim of this review is to describe some currently emerging tick-borne diseases, their causative viruses, and to discuss research on virus-tick interactions. Through focus on this area, future protein targets for intervention and vaccine development may be identified.

Recent Changes in Infectious Diseases in European Wildlife

“…Crimean-Congo hemorrhagic fever (CCHF) is caused by a zoonotic, vector-borne Orthonairovirus in the family Nairoviridae. The hemorrhagic syndrome caused by Crimean-Congo hemorrhagic fever Orthonairovirus (CCHFV) affects only humans, and the disease is of concern as an emerging zoonotic threat on the European continent and in the Middle East (Mansfield et al 2017).…”

Emerging tick-borne pathogens of public health importance: a mini-review

“…Successful prophylaxis of Lyme disease with preventative antibiotic treatment requires not only accurate tick species identification, but also the determination of the duration of tick feeding [32,34]. [37]. The Asian Omsk haemorrhagic fever virus causes a febrile disease that often displays severe haemorrhagic symptoms [38].…”

“…This group includes the Crimean-Congo haemorrhagic fever virus (CCHFV), which has a wide range of hosts and tick vectors in Eurasia and Africa [46][47][48]. The transmission and life cycle of CCHFV is well-characterized; nonetheless, it remains a critical emerging pathogen over much of its range, with various modes of transmission, including tickborne and directly from infected livestock [37,40]. CCHFV affects the nervous system and causes neurological manifestations that precede more dramatic haemorrhagic symptoms [46].…”

The Secret Life Inside Ticks

“…An important species of protozoa is Babesia bovis, which causes disease in cattle [2]. In addition, more than 38 species of viruses can use ticks as "buses" and threaten human and animal health [5]. These are just some examples of microbes that use ticks as vehicles, but there are many, many more.…”