(European, Classic, or Louse-Borne Typhus; Jail Fever)
Epidemic typhus is a rickettsial disease that is caused by Rickettsia prowazekii.
Rickettsiae are a type of bacteria that can live only inside the cells of other organisms (see also Overview of Rickettsial Infections). The rickettsiae that cause epidemic typhus typically live in people (the host).
Epidemic typhus occurs throughout the world. The infection is usually transmitted by body lice when their feces enters the body through breaks in the skin or sometimes through mucus membranes of the eyes or mouth. In the United States, people occasionally develop epidemic typhus after coming into contact with flying squirrels.
Symptoms of epidemic typhus begin suddenly about 7 to 14 days after bacteria enter the body. People have a fever and a headache and feel very tired. A rash appears 4 to 6 days later. It rapidly spreads to the armpits and upper torso. Untreated, the infection may be fatal, especially in people over 50.
The diagnosis of epidemic typhus is suggested by the symptoms. Doctors may do blood tests that detect antibodies to bacteria. However, these test cannot detect the antibodies until at least several days after the illness begins. Thus, these tests do not help doctors diagnose the infection immediately after someone becomes ill but can help confirm the diagnosis. To confirm the diagnosis, doctors may do an immunofluorescence assay or use the polymerase chain reaction (PCR) technique.
Treatment of epidemic typhus usually consists of the antibiotic doxycycline, given by mouth. People take the antibiotic until they improve and have had no fever for 24 to 48 hours, but they must take it for at least 7 days. Chloramphenicol is also effective but can have serious side effects and is not available in the United States.
People who have a lice infestation may be given lindane or malathion (which are prescription drugs) to eliminate the lice (see Lice Infestation : Treatment of Lice).
Brill-Zinsser disease is a recurrence of epidemic typhus, sometimes years after the first infection.
Some of the organisms that cause epidemic typhus remain in the body. They may become reactivated if a person's immune system is weakened.
Symptoms of Brill-Zinsser disease are almost always mild and resemble those of epidemic typhus. The fever lasts about 7 to 10 days. People may not have a rash.
Diagnosis and treatment of Brill-Zinsser disease are similar to those of epidemic typhus.