mGem: A tale as old as blood—do tick-borne pathogens exploit arthropod antioxidant defenses?

Effective control of tick-borne disease begins by first understanding how ticks acquire, harbor, and transmit pathogens. Over their lifetime, ticks encounter many sources of oxidative stress-inducing stimuli. Here, we explore the factors contributing to oxidative stress in ticks—including blood digestion, pesticide exposure, and pathogen infection—and then discuss how ticks counter this stress by employing antioxidant defenses. We highlight how non-tick-borne pathogens manipulate the host antioxidant response for survival and speculate that tick-borne pathogens may be acting similarly in the arthropod. We conclude by conjecturing that the robust antioxidant defenses that ticks have evolved to withstand the stress associated with hematophagy may also be inadvertently supporting the pathogens they carry.