This photograph of 2 ticks was taken during a 1972 study of disease carriers and pests found in and around migrant labor camps. Ticks commonly bite man, and some may spread serious diseases such as Rocky Mountain spotted fever caused by the bacterium, Rickettsia rickettsii. This disease is more commonly found in eastern and southeastern United States.

Picture & text from CDC/PHIL. For more information on source & for information on color coding used above for different types of ticks, see Tick Pictures from CDC