Tick-borne rickettsiae occur primarily in the climatic climax forest formations which still cover much of peninsular Malaya. The jungle rats (Rattus bowersi, R. canus, R. cremoriventer, R. edwardsi, R. rajah, R. sabanus, R. surifer, R. muelleri, and R. whiteheadi) with their ectoparasitic Dermacentor, Ixodes and Haemaphysalis ticks are the reservoirs of tick typhus and Q-fever rickettsiae.