Emerging Tick-Borne Diseases

Abstract

SUMMARY Increases in tick-borne disease prevalence and transmission are important public health issues. Efforts to control these emerging diseases are frustrated by the struggle to control tick populations and to detect and treat infections caused by the pathogens that they transmit. This review covers tick-borne infectious diseases of nonrickettsial bacterial, parasitic, and viral origins. While tick surveillance and tracking inform our understanding of the importance of the spread and ecology of ticks and help identify areas of risk for disease transmission, the vectors are not the focus of this document. Here, we emphasize the most significant pathogens that infect humans as well as the epidemiology, clinical features, diagnosis, and treatment of diseases that they cause. Although detection via molecular or immunological methods has improved, tick-borne diseases continue to remain underdiagnosed, making the scope of the problem difficult to assess. Our current understanding of the incidence of tick-borne diseases is discussed in this review. An awareness of the diseases that can be transmitted by ticks in specific locations is key to detection and selection of appropriate treatment. As tick-transmitted pathogens are discovered and emerge in new geographic regions, our ability to detect, describe, and understand the growing public health threat must also grow to meet the challenge.

General Microbiota of the Soft Tick Ornithodoros turicata Parasitizing the Bolson Tortoise (Gopherus flavomarginatus) in the Mapimi Biosphere Reserve, Mexico

“…Tick-borne bacteria have been largely studied in hard ticks (family Ixodidae) Amblyomma spp., Dermacentor spp., Haemaphysalis spp., Hyalomma spp., Ixodes spp., and Rhipicephalus spp. , where zoonotic bacteria Anaplasma phagocytophilum , Coxiella burnetii , Ehrlichia chaffensis , Francisella tularensis , and Rickettsia rickettsi have been reported [ 7 , 8 , 9 , 10 ]. In soft ticks (family Argasidae), most studies have focused on the genus Ornithodoros , which comprises of more than 60% of the family [ 1 , 11 ].…”

Molecular Evidence of Novel Spotted Fever Group Rickettsia Species in Amblyomma albolimbatum Ticks from the Shingleback Skink (Tiliqua rugosa) in Southern Western Australia

“…Ticks are important vectors of infectious disease in humans and animals [1]. Ticks preceded mosquitos as being the first arthropods ever associated with the transmission of infection to a healthy vertebrate animal (Texas cattle fever), as determined by Theobald Smith and colleagues in 1889.…”

Failed Disruption of Tick Feeding, Viability, and Molting after Immunization of Mice and Sheep with Recombinant Ixodes ricinus Salivary Proteins IrSPI and IrLip1

“…In this last regard, recent transcriptomic studies using next-generation sequencing (NGS) techniques have led to the identification of several unexpected bacteria, viruses, and parasites in I. ricinus ticks from Eastern France, some of them representing potential pathogens for humans or animals [ 6 , 7 , 8 ]. To date, the intensification of human and animal movements and socioeconomic and environmental changes have led to the redistribution of certain tick species—that is, an extension of seasonal transmission periods and geographical distribution, as well as the appearance of TBD in previously unaffected areas, highlighting the urgent need to find better methods of control [ 9 , 10 , 11 , 12 ].…”