Typhus is a rickettsial disease caused by one of two organisms, Rickettsia prowazekii (epidemic typhus and Brill disease) and Rickettsia typhi (murine or endemic typhus). Epidemic typhus and Brill disease are uncommon in the United States.

Murine typhus occurs in the southeastern and southern states. There are less than 100 cases per year. Murine typhus is a milder form and is seldom fatal (less than 2%).

It is frequently seen in the summer and fall and typically lasts two to three weeks. Risk factors for murine typhus include exposure to rat fleas or rat feces, or exposure to other animals (such as cats, opossums, raccoons, skunks, and rats).

Epidemic typhus occurs in poor hygienic conditions (which is why it is sometimes called "jail fever"), usually when the temperature is cold. It is spread by lice. Although very rare in the United States, it has sometimes been spread by the lice and fleas of flying squirrels.

Brill-Zinsser disease is a mild form of epidemic typhus, caused by reactivation of the disease in the body of someone who has been previously infected after a long period of dormancy. This is more common in the elderly.

• headache
• backache
• arthralgia
• fever, extremely high (105 to 106 degrees Fahrenheit) and may last up to two weeks
• rash that begins on the trunk and spreads peripherally (The rash is made up of dull red macules that may become slightly papular after the initial appearance may last only a few hours.)
• nausea and vomiting in most patients
• hacking, dry cough
• abdominal pain

• severe headache
• fever, high (104 degrees Fahrenheit)
• cough in 70% of patients
• arthralgia and myalgia, (muscle pain) severe
• chills
• falling blood pressure
• stupor
• delirium
• rash that begins on chest and spreads to rest of trunk and extremities, but not to palms and soles
• early rash is faint and rose colored and fades with pressure (Later the lesions become dull, red, and do not fade. People with severe typhus may also develop petechiae.)
• lights appear very bright, and exposure to light may hurt the eyes

• CBC may show anemia and low platelets
• low serum sodium
• low albumin levels in the blood
• mildly increased liver enzymes
• mild renal failure
• antibody tests to typhus should be elevated

Without treatment death may occur in 10 to 60% of patients with epidemic typhus. Patients over the age of 60 have the highest risk of death. With timely antibiotic therapy, the affected person is expected to recover completely.

Less than 2% of untreated patients with murine typhus may die, and appropriate antibiotic therapy will cure virtually all patients.

• renal insufficiency
• pneumonia
• central nervous system damage