JACKSON, Wyo. — After the first year of its tick surveillance program, Teton County Weed & Pest (TCWP) can confirm that a tick of “medical significance” has moved into Wyoming and established in the state.
The Centers for Disease Control and Prevention (CDC) define “establishment” as more than six ticks of a single life stage or more than one life stage collected per county within a 12-month period.
Mikenna Smith, entomologist with TCWP who developed this pioneering tick surveillance program, tells Buckrail the program’s first year included both active and passive surveillance. Passive surveillance consisted of collecting samples mailed in from other Weed & Pest Districts, the Wyoming Game and Fish Department, the Department of Agriculture, conservation districts and individuals out hiking, which yielded over 400 tick samples.
These samples were what allowed TCWP to determine that the American dog tick has established in Wyoming.
Smith confirms the American dog tick was found in three counties: Natrona (reported), Campbell (reported) and Sheridan (established). This information will now be submitted to the Wyoming Department of Health and the CDC.
“Having the American dog tick on the list is very important for informing public health,” Smith tells Buckrail.
According to Smith, the American dog tick can be a vector for tularemia, Q fever, Rocky Mountain spotted fever, tick paralysis, bovine anaplasmosis and potentially human anaplasmosis, although this last one is very early in its research.
“For this tick to potentially be transmitting human anaplasmosis is a really big deal.”
Mikenna Smith, entomologist with TCWP
“In this ecosystem, I’m not sure how it will behave in terms of pathogen spreading,” Smith says. “All of those pathogens are pretty nasty. The one I’m most interested in learning about is if it can transmit human anaplasmosis. Anaplasmosis in the U.S. is often caused by a different tick; for this tick to potentially be transmitting human anaplasmosis is a really big deal.”
The CDC writes that human anaplasmosis is a bacterial disease that causes fever, chills, severe headache, muscle aches, nausea, vomiting, diarrhea and loss of appetite. More severe symptoms include respiratory failure, bleeding problems, organ failure and death, but the disease can be treated with antibiotics.
Smith tells Buckrail that there are currently four known medically significant ticks in Wyoming, all carrying what she calls a “laundry list” of pathogens. As of now, the Rocky Mountain wood tick is the only one that scientists have confirmed can spread Colorado tick fever virus. Research is looking into whether the American dog tick can also spread this virus because Smith says the species is starting to move into the Rocky Mountain wood tick habitat.
“This program has made a lot of progress,” Smith says. “We’ve got a lot of data, we’ve got a million more questions than we have answers, but we have the ability to start answering some of these questions.”
For those interested in being citizen scientists with TCWP’s “Tick Blitz” active surveillance this May and contributing to the research, email Smith at msmith@tcweed.org. TCWP’s vector-borne diseases page with information on ticks, passive surveillance and a citizen science form can be accessed here.
