Park Hill Vet: The Bugs of Summer
Part II: Ticks And More Ticks
By Margot K. Vahrenwald, DVM, CVJ
For the GPHN
Last month we discussed the predominant flying vector of human and animal disease – mosquitos. Now let’s talk about the one that causes much more of a skin-crawling response: ticks.
For the past 20 years, the Companion Animal Parasite Council (CAPC) has issued annual forecasting maps for the most common parasites that are source of disease for pets and people. Vector-borne pathogens such as heartworm disease, Lyme disease, ehrlichiosis, anaplasmosis and many others have long been spreading across the country. There are many reasons, but the biggest include changes in distribution and prevalence of different vector populations, the increased mobilization of pets for rehoming to different states, changes in wildlife populations and changes in habitat that bring parasites closer to us and our pets.
Just like mosquitos and heartworms, this year in Colorado will mark the highest percentage increases for risks for tick-borne diseases — particularly for the Lone Star Tick that has rapidly moved from south central Texas along the Front Range and up into central Wyoming.
When creating their forecasting, CAPC uses test data from as many sources as possible including national and local veterinary reference labs such as IDEXX, the Colorado Department of Environment and Public Health and veterinary teaching hospital diagnostic labs. But they are also quick to point out that these numbers are likely underestimations because they represent only about 30 percent of the pet population.
Here’s the big kicker, the Lone Star Tick is the primary tick vector for multiple Ehrlichia species and Anaplasma species, often in the same tick. And, the majority of Ehrlichia and Anaplasma species that infect and cause disease in dogs are also well-established as zoonotic agents infecting and causing disease in humans.
Over the past several years, Colorado has seen and is seeing higher numbers of the deer ticks (Ixodes species) that carry Lyme disease, the Brown Dog tick (Rhipicephalus sanguineas) which can carry Anaplasma, Lyme, Babesia, Ehrlichia canis, etc. That’s in addition to our already established Rocky Mountain Wood tick and other Dermacentor species that are the carriers for Rocky Mountain Spotted Fever and Tularemia.
Each of these tick species have some seasonality and preferences for locations, mostly grasslands, brushy areas and woodlands. But the Brown Dog tick prefers to live as close as possible to its primary target by moving indoors. They also all have variable timetables for being attached to a host for a blood meal before the female lays eggs in their environment.
The majority of them will attach for 3 to 5 days but some, like the Rocky Mountain Wood tick or deer ticks, can stay attached for 10 days or longer. The creepy American Dog tick specializes in fast attack and only attaches for 10 to 120 minutes.
Cats can be infected by ticks as well, but seem to have more resistance as little is known and described about various tick-borne infections in felines.
Creeped out enough yet? What can you do to protect your dog? Speak with your veterinarian for the best options in oral to topical preventatives. And protect everybody appropriately when out hiking.
(Editor’s Note: Last month’s column, the Bugs of Summer Part I, can be read at this link: greaterparkhill.org/news-and-opinion/park-hill-vet-the-forecast-is-heartworm/)
Dr. Margot Vahrenwald is the owner of Park Hill Veterinary Medical Center at 2255 Oneida St. For more information, visit parkhillvet.com