Scrub typhus or Bush typhus is a form of typhus caused by the intracellular parasite Orientia tsutsugamushi, a Gram-negative α-proteobacterium of family Rickettsiaceae. Although the disease is similar in presentation to other forms of typhus, its pathogen is not anymore included in genus Rickettsia with the typhus bacteria proper, but in Orientia. The disease is thus frequently classified separately from the other typhi. Symptoms include fever, headache, muscle pain, cough, and gastrointestinal symptoms. More virulent strains of O. tsutsugamushi can cause hemorrhaging and intravascular coagulation. Morbilliform rash, eschar, splenomegaly and lymphadenopathies are typical signs. Pneumonitis, encephalitis, and myocarditis occur in the late phase of illness. With therapy, the fever will break within 36 hours, but if left untreated, complications or death may occur.