Rickettsia parkeri was initially identified in Amblyomma maculatum ticks in 1937 by Dr. R. Parker. It was not until 2004 that confirmed human infections were reported and this species took its place as a human pathogen. Reports from the U.S. Gulf Coast extending inland, as well as parts of Central and South America, have reported R. parkeri. In Uruguay this species was also found in A. triste ticks and cases have been reported in the range of this tick.