 From 2003 to 2016, cases increased to 1394 with 247 deaths.Rocky Mountain spotted fever (or "black measles" because of its characteristic rash) was recognized in the early 1800s, and in the last 10 years of the 1800s (1890–1900) it became very common, especially in the Bitterroot Valley of Montana.The disease was originally noted to be concentrated on the west-side of the Bitterroot river.