Murine (Endemic) Typhus
(Rat-Flea Typhus; Urban Typhus of Malaya)
Murine typhus is a rickettsial disease that is caused by Rickettsia typhi and Rickettsia felis.
Rickettsiae are a type of bacteria that can live only inside the cells of other organisms (see also Overview of Rickettsial Infections). Murine means related to rats and mice. Thus, the rickettsiae that cause murine typhus live mainly in rats and mice (the hosts).
Murine typhus occurs throughout the world, although not many people are infected. The infection is transmitted to people by rat fleas and probably cat fleas.
Symptoms of murine typhus begin about 6 to 18 days after bacteria enter the body. People have shaking chills, fever, and a headache. The fever lasts about 12 days. A rash may appear a few days after other the other symptoms. At first, it occurs only in a few places on the torso, then spreads to the limbs. Murine typhus rarely causes death, but death is more likely in older people.
The diagnosis of murine typhus is suggested by symptoms. Doctors may do blood tests that detect antibodies to the 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 murine typhus usually consists of the antibiotic doxycycline, given by mouth. People take the antibiotic until they improve and have had no fever for 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.
Prevention involves measures to reduce the number of rats and rat fleas.