Stepping on a hidden cluster of lone star tick eggs can trigger what entomologists call a tick bomb: hundreds or thousands of larval ticks swarm onto the person or animal that disturbed the nest. Jonathan Oliver, a public health entomologist at the University of Minnesota, explains that female lone star ticks lay clutches of roughly 1,000 to 2,000 eggs, and the larvae will bite immediately. In the U.S., lone star tick larvae are the only species that creates this phenomenon on humans.
Because these larvae have not yet taken a blood meal, they rarely transmit bacterial pathogens. However, Oliver notes that unfed larvae can carry the protein responsible for alpha-gal syndrome, the red meat allergy, and there is rare evidence of mothers passing viruses such as Bourbon and Heartland virus to offspring. As lone star ticks expand their range with climate change, clinicians in the Northeast, Midwest, and New England may encounter more patients with these bites.
Recognizing a tick bomb can be challenging. A nurse practitioner in North Carolina recently posted images of a patient's pruritic rash with moving crusts, initially thought to be tick-bomb larvae. Oliver, however, believes the specimen looked more like a brown dog tick, a species that can reproduce indoors and cause repeated exposures. Regardless of the exact species, tick bomb encounters are being reported from Florida to Long Island, and as Oliver puts it, "No one wants a tick bomb on their ankle."