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Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert

Molly J Bechtel·K. Kristina Drake·Todd Esque·Nathan C Nieto·Jeffrey T. Foster·Mike B Teglas
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Abstract

Ticks transmit pathogens and parasitize wildlife in turn causing zoonotic diseases in many ecosystems. Argasid ticks, such as Ornithodoros spp., harbor and transmit Borrelia spp., resulting in tick-borne relapsing fever (TBRF) in people. In the western United States, TBRF is typically associated with the bite of an infected Ornithodoros hermsi tick found in habitats at high elevations (>1500 ft). This report describes the first TBRF cases in people in the Mojave Desert (Clark County, NV). Individuals documented in these case studies were exposed to Ornithodoros ticks during excavation of soil burrows associated with Mojave Desert tortoises ( Gopherus agassizii ), with bacteria from one of the human case's blood sample genetically matching to Borrelia turicatae as determined by quantitative PCR and sequencing. Our findings should serve as a precaution to individuals working with tortoises or animal burrows, or those in contact with Ornithodoros ticks in this region.

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Vector-Borne and Zoonotic DiseasesArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 34.66935854524543° to 36.465471886798134° latitude; -116.630859375° to -113.93920898437499° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Molly J Bechtel, K. Kristina Drake, Todd Esque, Nathan C Nieto, Jeffrey T. Foster, Mike B Teglas. 2021. Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert. https://doi.org/10.1089/vbz.2021.0005

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