<unk>  is the most severe and most frequently reported rickettsial illness in the United States.  Some synonyms for<unk>  in other countries include “tick typhus,” “Tobia fever” (Colombia), “São Paulo fever” or “febre maculosa” (Brazil), and “fiebre manchada” (Mexico). The disease is caused by Rickettsia rickettsii, a species of bacteria that is spread to humans by Ixodid ticks (Dermacentor). Initial signs and symptoms of the disease include sudden onset of fever, headache, and muscle pain, followed by development of a rash. The disease can be difficult to diagnose in the early stages, and without prompt and appropriate treatment it can be fatal.  The name<unk>  is somewhat of a misnomer.  Beginning in the 1930s, it became clear that this disease occurred in many areas of the United States other than the<unk><unk>  region. It is now recognized that this disease is broadly distributed throughout the continental United States, and occurs as far north as Canada and as far south as Central America, Mexico, and parts of South America.  Between 1981 and 1996, this disease was reported from every U.S. state except Hawaii, Vermont, Maine, and Alaska.<unk>  remains a serious and potentially life-threatening infectious disease today. Despite the availability of effective treatment and advances in medical care, approximately 3% to 5% of individuals who become ill with<unk>  still die from the infection.  However, effective antibiotic therapy has dramatically reduced the number of deaths caused by<unk> ; before the discovery of tetracycline and chloramphenicol in the late 1940s, as many as 30% of persons infected with R. rickettsii died.
Rocky Mountain spotted fever
Trench fever
Chikungunya
Blackwater fever
Cotton fever
Yellow fever
Boutonneuse fever
Crimean-Congo hemorrhagic fever