Earlier this year I wrote about how 2017 is expected to be a risky year for Lyme disease, particularly for the mid-Atlantic and New England areas. If my last hike with my Border Collie, Scuttle, was any indication, ticks are going to be the bane of our existence this summer and fall!
Not only is the problem growing worse in known problem areas, but the reach of tick borne disease is also spreading. Experts have warned veterinarians practicing on the edges of endemic areas, such as the Dakotas and Kentucky, to be aware of encroachment. Western Pennsylvania has already reached endemic status.
In my original article, I wrote about the standard adage that it takes 24-36 hours for a tick to transmit disease. But it turns out that advice may be problematic. A reader brought to my attention a few studies that show disease transmission can happen in far less time.
Researchers from East Carolina University and North Carolina State University scoured the literature to see just how accurate the 24-36 hour guideline was. With approximately 40 tick species in the United States, it would make sense that they all don’t pose the same risk.
One study found that soft ticks (Ornithodoros spp.) could transmit the virus behind Tick-Borne Relapsing Fever to mice in as few as 30 seconds of attachment. Another study found that ticks carrying Rocky Mountain Spotted Fever (R. rickettsii) could infect hosts in as little as ten hours.
Much of the research on tick attachment times were conducted on mice, often in studies where multiple ticks were placed on the subjects. So the findings can be hard to compare. However, given the variable virus transmission times, I think the 24-36 hour guide may give us a false sense of security. With the severe forecast for 2017, we must be extra vigilant about guarding ourselves and our pups against ticks.