A recent review paper provided insight on the microbiomes of North American ticks important to veterinary medicine.
Ticks hold important significance as disease vectors in veterinary medicine. “Ticks were the first arthropod to be associated with transmission of a disease agent,” wrote the authors of a Frontiers in Veterinary Science review paper on tick microbiomes. This association was first discovered in the late 1800s when Rhipicephalus (Boophilus) ticks were identified as transmitters of Babesia bigemina, which causes Texas cattle fever.
Ticks’ role as vectors of pathogenic microorganisms has been researched extensively. In recent years, there has been increased research interest in the tick microbiome. Studying this microbiome, the authors noted, can provide insight on how ticks maintain and transmit pathogens and provide clues for developing novel tick and pathogen control strategies.
Tick Microbiomes in North America
Next-generation sequencing has enabled improved detection of tick microbial communities. These communities consist largely of symbiotic microorganisms that are either obligate or facultative and, quite likely, nonpathogenic. It is possible, the authors wrote, that the pathogenic microorganisms have little impact on the rest of the microbiome.
A previous study determined that the phylum Proteobacteria predominates in North American tick microbiomes. In the current review paper, the authors highlighted the microbiomes of several ticks of veterinary importance in North America.
Factors Affecting Tick Microbiome Composition
Many factors can alter a tick’s microbiome. For example, deforestation and warmer winters can increase a tick’s geographic distribution and exposure to different microbial communities. In addition, tick feeding and co-feeding can lead, respectively, to the acquisition and exchange of microorganisms. Also, pathogens themselves can alter the tick microbiome.
Importantly, imbibing blood can affect a tick’s microbiome composition. The blood meal can contain antimicrobial compounds like ubiquitin. Also, imbibing blood can alter a tick’s gut osmolarity, which could affect a microorganism’s motility, morphology, and expression of virulence factors in the gut.
In the future, analytic methods like proteomics and metabolomics could help “uncover some of the answers to the interaction between the tick host and its microbiome, and in turn how these interactions impact the presence of pathogens,” the authors concluded.
Dr. Pendergrass received her Doctor of Veterinary Medicine degree from the Virginia-Maryland College of Veterinary Medicine. Following veterinary school, she completed a postdoctoral fellowship at Emory University’s Yerkes National Primate Research Center. Dr. Pendergrass is the founder and owner of JPen Communications, a medical communications company.