Dangerous to humans and dogs, Rocky Mountain Fever, along with several other tickborne infections, is on the rise.

According to the Centers for Disease Control and Prevention (CDC), the incidence of Rocky Mountain Spotted Fever (RMSF) has been increasing for decades. Overall, RMSF joins a cadre of infections carried or "vectored" by ticks that are demanding increasing attention from the healthcare community including:

For a variety of reasons that may include changes to surveillance techniques, improved diagnostics, warming climates, infectious spread, and expansion of geographic range, tickborne diseases altogether appear to be on the upswing as a public health menace. Powassan virus, an unusually severe viral infection, has recently spread to the tick, Ixodes scapularis, which carries Lyme disease. Three types of ticks carry RMSF: the brown dog tick (Rhipicephalus sanguineus), the Rocky Mountain wood tick (Dermacentor andersoni), and the American dog tick, (Dermacentor variabilis).

While this map illustrates the range of the dog tick, the Rocky Mountain Wood tick is found primarily in the Rocky Mountain States, while the American Dog tick ranges across the entirety of the US from the Rocky Mountains eastward. The essential point here is that ticks carrying RMSF are all across the country.

The geographic range of the brown dog tick includes the territory of the American dog tick, and the Rocky Mountain wood tick. Image via CDC

There are two myths to debunk about RMSF.

Although the disease is transmitted by a tick whose primary host is dogs, that does not mean that only dogs get the disease. Also, the term "Rocky Mountain" is deceiving. Since the vector for RMSF is widespread, ticks can transmit the disease from the Pacific to the East coast of the US.

Tickborne diseases are in the news for a good reason. The infections are sometimes hard to diagnose, they can be severe, and tick season is just about here as people start enjoying time outside. So what do we know about Rocky Mountain Spotted Fever?