Endemic (murine) typhus is caused by Rickettsia typhi and occurs worldwide. Cases have been increasing in the United States over the past 15 years, primarily in Texas and California; it also occurs in Hawaii. It is transmitted from rodents to humans by flea bites or aerosolized flea feces; 7-14 days after the flea bite, there is a rapid onset of flu-like illness (fever, chills, nausea, severe headache, and myalgias) lasting 2 weeks. A generalized macular, papular, and/or petechial eruption develops in 50% of cases that can persist for up to 10 days. Mental status changes and renal dysfunction may also occur. Without treatment, the mortality rate is 1%-2%, most commonly in elderly patients. Many cases are subclinical.