Howard Taylor Ricketts (February 9, 1871 – May 3, 1910) was an American pathologist after whom the family Rickettsiaceae and the order Rickettsiales are named.

He later worked in the Bitterroot Valley of Montana and at the University of Chicago on Rocky Mountain spotted fever.

This early pathology, entomology and epidemiology research in Hamilton, Montana led to the eventual formation of the Rocky Mountain Laboratories there.

In 1910, Ricketts became interested in a strain of murine-carried typhus known as tabardillo due to a major outbreak in Mexico City, and the apparent similarity of the disease to spotted fever.

[5][6] Noteworthy recipients of the Ricketts Prize include Julian Herman Lewis (1913),[7] Lauretta Bender (1923),[8] Sara Elizabeth Branham (1924), G. M. Dack (1925), and Maurice Hilleman (1945).