As it became clear that the species differed significantly from other Rickettsia, it was first elevated to a subgenus named after Cox, Coxiella, and then in 1948 to its own genus of that name, proposed by Cornelius B. Philip, another RML researcher.
Kada je postalo jasno da se vrsta razlikuje značajno od drugih Rickettsia, tada je vrsta svrstana najprije kao podrod nazvan po Coxu, Coxiella, a zatim je 1948. klasificiran kao rod Coxiella kako je predložio Cornelius B. Philip, još jedan RML istraživač.