Which disease is tick-borne and has an incubation period of 3-10 days, leading to a rash?

The correct answer is Rocky Mountain Spotted Fever. This disease is transmitted through tick bites, primarily from the American dog tick and the Rocky Mountain wood tick. After the initial bite, the incubation period for Rocky Mountain Spotted Fever typically ranges from 3 to 10 days, which coincides with the parameters given in the question.

During this incubation period, the bacteria that cause the disease—Rickettsia rickettsii—multiply and are eventually released into the bloodstream. One of the hallmark symptoms of this disease is the characteristic rash that usually appears a few days after the onset of fever and other initial symptoms. This rash typically starts at the wrists and ankles before spreading to the rest of the body.

In contrast, Colorado Tick Fever is primarily characterized by fever and does not consistently feature a rash. Lyme Disease, while also tick-borne, has a longer incubation period and is often associated with a particular type of rash called erythema migrans, which differs from the rash seen in Rocky Mountain Spotted Fever. Hantavirus is not transmitted via ticks but is associated with rodent droppings and urine, making it a completely unrelated disease to the question.