ADAM Health Encyclopedia

Typhus

Definition

Typhus is a bacterial disease spread by lice or fleas.

Alternative Names

Causes

Typhus is caused by one of two types of bacteria: Rickettsia typhi or Rickettsia prowazekii. The form of typus depends on which type of bacteria causes the infection.

Rickettsia typhi causes murine or endemic typhus. Endemic typhus is uncommon in the United States. It is usually seen in areas where hygiene is poor and the temperature is cold. Endemic typhus is sometimes called "jail fever." Lice and fleas of flying squirrels spread the bacteria.

Murine typhus occurs in the southeastern and southern United States, often during the summer and fall. It is rarely deadly. Risk factors for murine typhus include:

• Exposure to rat fleas or rat feces
• Exposure to other animals (such as cats, opossums, raccoons, skunks, and rats)

Rickettsia prowazekii causes epidemic typhus and Brill-Zinsser disease. Brill-Zinsser disease is a mild form of epidemic typhus. It occurs when the disease re-activates in a person who was previously infected. It is more common in the elderly.

Symptoms

Symptoms of murine typhus may include:

• Abdominal pain
• Backache
• Dull red rash that begins on the middle of the body and spreads
• Extremely high fever (105 - 106 degrees Fahrenheit), which may last up to 2 weeks
• Hacking, dry cough
• Headache
• Joint pain (arthralgia)
• Nausea
• Vomiting

Symptoms of endemic typhus may include:

• Chills
• Cough
• Delirium
• High fever (104 degrees Fahrenheit)
• Joint pain (arthralgia)
• Lights that appear very bright; light may hurt the eyes
• Low blood pressure
• Rash that begins on the chest and spreads to the rest of the body (except the palms of the hands and soles of the feet)
• Severe headache
• Severe muscle pain (myalgia)
• Stupor

The early rash is a light rose color and fades when you press on it. Later, the rash becomes dull and red and does not fade. People with severe typhus may also develop small areas of bleeding into the skin (petechiae).

Exams and Tests

A complete blood count (CBC) may show anemia and low platelets. Other blood tests for typhus may show:

• High level of typhus antibodies
• Low level of albumin
• Low sodium level
• Mild kidney failure
• Mildly high liver enzymes

Treatment

Treatment includes antibiotics such as:

• Doxycycline
• Tetracycline
• Chloramphenicol (less common)

Tetracycline taken by mouth can permanently stain teeth that are still forming. It is usually not prescribed for children until after all of their permanent teeth have grown in.

Patients with epidemic typhus may need intravenous fluids and oxygen.

Outlook (Prognosis)

Without treatment, death may occur in 10 - 60% of patients with epidemic typhus. Patients over age 60 have the highest risk of death. Patients who receive treatment quickly should completely recover.

Less than 2% of untreated patients with murine typhus may die. Prompt antibiotic treatment will cure nearly all patients.

Possible Complications

• Renal insufficiency
• Pneumonia
• Central nervous system damage

When to Contact a Medical Professional

Call your health care provider if you develop symptoms of typhus. This serious disorder can require emergency care.

Prevention

Avoid areas where you might encounter rat fleas or lice. Good sanitation and public health measures reduce the rat population.

Measures to get rid of lice when an infection has been found include:

• Bathing
• Boiling clothes or avoiding infested clothing for at least 5 days (lice will die without feeding on blood)
• Using insecticides (10% DDT, 1% malathion, or 1% permethrin)

Bechah Y, Capo C, Mege JL, Raoult D. Epidemic typhus. Lancet Infect Dis. 2008;8:417-426.