Ticks are yucky, absolutely, but it’s the diseases that ticks carry that are our greatest concern. Tick and tick-borne disease incidence is increasing in Colorado.
Ticks are particularly common at higher elevations, and there are 27 species of ticks in Colorado. Rocky Mountain wood ticks account for most human encounters with ticks in Colorado. Human tick-borne diseases are not as common in Colorado as on the East Coast or Southwest, but Colorado tick fever, Rocky Mountain spotted fever, tularemia, and relapsing fever occur.
Many species of ticks found in CO are ‘three-host’ ticks, meaning larvae feed on small mammals (rodents), then nymphs feed on other small mammals (including dogs), then adults feed on larger mammals (deer and also humans).
Ticks climb on vegetation to seek their host using chemical and mechanical signals, then latch onto animals as they brush by. Dogs are quite susceptible to tick interactions while outdoors, on hikes, and even just in the backyard. After a dog or other mammal is bitten by a tick, pathogens in the tick's saliva can be transmitted to the mammal's blood and infect the host. They can cause acute infections, but sometimes are not discovered until the dog is chronically ill.
The tick-borne diseases that primarily affect dogs attack the red and white blood cells of the immune system. Clinical signs for tick-borne disease include fever, lethargy, inappetence, weight loss, edema, joint pain, and mobility issues.
Year-round tick coverage is recommended for several reasons. Ticks have been shown to bloom at temperatures above 40 degrees for 3 days, heat indexes have risen, allowing ticks to incubate diseases, and pets are being brought into Colorado from more heavily tick-burdened regions.