Human Tick-Borne Diseases in Australia

Abstract

There are 17 human-biting ticks known in Australia. The bites of Ixodes holocyclus, Ornithodoros capensis, and Ornithodoros gurneyi can cause paralysis, inflammation, and severe local and systemic reactions in humans, respectively. Six ticks, including Amblyomma triguttatum, Bothriocroton hydrosauri, Haemaphysalis novaeguineae, Ixodes cornuatus, Ixodes holocyclus, and Ixodes tasmani may transmit Coxiella burnetii, Rickettsia australis, Rickettsia honei, or Rickettsia honei subsp. marmionii. These bacterial pathogens cause Q fever, Queensland tick typhus (QTT), Flinders Island spotted fever (FISF), and Australian spotted fever (ASF). It is also believed that babesiosis can be transmitted by ticks to humans in Australia. In addition, Argas robertsi, Haemaphysalis bancrofti, Haemaphysalis longicornis, Ixodes hirsti, Rhipicephalus australis, and Rhipicephalus sanguineus ticks may play active roles in transmission of other pathogens that already exist or could potentially be introduced into Australia. These pathogens include Anaplasma spp., Bartonella spp., Burkholderia spp., Francisella spp., Dera Ghazi Khan virus (DGKV), tick-borne encephalitis virus (TBEV), Lake Clarendon virus (LCV), Saumarez Reef virus (SREV), Upolu virus (UPOV), or Vinegar Hill virus (VINHV). It is important to regularly update clinicians' knowledge about tick-borne infections because these bacteria and arboviruses are pathogens of humans that may cause fatal illness. An increase in the incidence of tick-borne infections of human may be observed in the future due to changes in demography, climate change, and increase in travel and shipments and even migratory patterns of birds or other animals. Moreover, the geographical conditions of Australia are favorable for many exotic ticks, which may become endemic to Australia given an opportunity. There are some human pathogens, such as Rickettsia conorii and Rickettsia rickettsii that are not currently present in Australia, but can be transmitted by some human-biting ticks found in Australia, such as Rhipicephalus sanguineus, if they enter and establish in this country. Despite these threats, our knowledge of Australian ticks and tick-borne diseases is in its infancy.

Lyme Endocarditis as an Emerging Infectious Disease: A Review of the Literature

“…In Asia, Borrelia burgdorferi infection has been reported in countries including China, Korea, Japan, Indonesia, and Nepal and in eastern Turkey (Jaenson and Lindgren, 2011;Heinz et al, 2015). Beside the above-mentioned areas, cases were reported in more tropical locales, and LD may exist in Australia (Dehhaghi et al, 2019).…”

Evasins: Tick Salivary Proteins that Inhibit Mammalian Chemokines

“…The expression of Evasins by diverse tick species suggests that they play important roles in promoting tick blood-feeding and survival. Considering that ticks are vectors for viral and bacterial pathogens in humans and both domestic and wild animals [59], it will be important to assess the contributions of Evasins to the spread of infectious diseases and to examine their potential as targets for tick control strategies such as vaccination.…”

The Use of Tick Salivary Proteins as Novel Therapeutics

“…The infections transmitted by ticks can be passive, such as from pathogens like poxviruses or apicomplexa present in blood on the tick hypostome or regurgitated during feeding (Tuppurainen et al, 2011; Hammer et al, 2016), and/or active when ticks are vectors for pathogens. Ticks can transmit bacteria of the genera Borrelia , Anaplasma, Rickettsia, Francisella , and others; protozoan parasites of the genus Babesia ; and several viruses, with tick-borne encephalitis virus a major tick-transmitted viral pathogen in humans (Swanson et al, 2006; Coipan et al, 2013; Berggoetz et al, 2014; Jahfari et al, 2016; Kazimirova et al, 2017; Dehhaghi et al, 2019). Early works on tick saliva (Wikel, 1982; Ribeiro et al, 1985) showed that ticks actively modulate and/or inhibit host defense mechanisms, thus enabling the tick to complete its blood meal and facilitate pathogen transmission, as reviewed elsewhere (Francischetti et al, 2009; Wikel, 2013; Kotal et al, 2015).…”