Epidemic typhus is a rickettsial disease that is caused by Rickettsia prowazekii bacteria and spread by infected body lice and occasionally through contact with wild flying squirrels.
People with epidemic typhus have a high fever, an intense headache, extreme exhaustion, and a rash.
To diagnose the infection, doctors test a sample of the rash or do blood tests.
The antibiotic doxycycline is used to treat this infection.
Washing and drying infested clothes and bedding at high temperatures can kill lice and help prevent the infection from spreading.
Epidemic typhus is caused by Rickettsia prowazekii bacteria, which are spread to people by an infected body louse.
CDC/James Gathany
Rickettsiae are a type of bacteria that can live and multiply only inside the cells of a host organism, such as an animal or person, and cannot survive on their own in the environment. The rickettsiae that cause epidemic typhus typically live in people (the host). But, in the United States, these rickettsiae can also live in wild flying squirrels because lice on the squirrels may be infected with rickettsiae.
Stan/stock.adobe.com
Epidemic typhus occurs throughout the world. it is called "epidemic" typhus because in the past, it caused outbreaks (epidemics) that killed large numbers of people. Such outbreaks are now rare, but infections have occurred in Africa, Central and South America, Eastern Europe, and France. Epidemic typhus spreads most easily in crowded, unhygienic conditions, such as those that occur during famine or war, and among people who are living in refugee camps, areas of extreme poverty, or prisons or are experiencing homelessness or civil unrest.
Epidemic typhus is usually transmitted by body lice when their feces enter the body through breaks in the skin, such as scratches or wounds, or sometimes through the mucus membranes of the eyes or mouth. In the United States infection is rare, but people occasionally develop epidemic typhus after coming into contact with wild flying squirrels.
Symptoms of Epidemic Typhus
Symptoms of epidemic typhus begin suddenly about 8 to 16 days after Rickettsia prowazekii bacteria enter the body. People have a high fever (104° F [40° C]) and an intense headache and feel very tired. A rash of small, pink spots appears 4 to 6 days later. A red rash usually begins on the chest and spreads to the arms and legs. It does not spread to the palms, soles, or face. Later, the rash becomes dark.
This photo shows the red rash on a person with epidemic typhus.
CDC
Sometimes the spleen enlarges. If the infection is severe, blood pressure may become very low, the kidneys may malfunction, and gangrene (death of tissue) and/or pneumonia may develop.
Epidemic typhus is rarely fatal, but the risk of death increases with age.
Diagnosis of Epidemic Typhus
A doctor's evaluation
Blood tests
Biopsy and testing of the rash
Doctors initially base the diagnosis of epidemic typhus on the person's symptoms (such as sudden high fever and headache), particularly if the person has body lice, has been in contact with flying squirrels, or has been in an area where epidemic typhus occurs.
To confirm the diagnosis, doctors may take a blood sample and do an immunofluorescence assay to detect antibodies to the bacteria. This test may need to be repeated a few weeks later to detect a rise in antibodies. Or they may take a blood or tissue sample and do the polymerase chain reaction (PCR) test to make copies of the bacteria's DNA, so that the bacteria can be detected more rapidly. Doctors also test blood to diagnose Brill-Zinsser disease.
Sometimes doctors remove a sample of the rash (biopsy) and test if for antigens produced by the bacteria. See also Tests That Detect Antibodies to or Antigens of Microorganisms.
Treatment of Epidemic Typhus
Antibiotics
Doctors typically give people of all ages who have epidemic typhus the antibiotic doxycycline. Doxycycline is usually given by mouth (orally). People take the antibiotic until they improve and have not had a fever for 24 to 48 hours, and they must take it for at least 7 to 10 days.
Although doxycycline can cause tooth staining in children younger than 8 years old, a short, 5- to 10-day course of doxycycline in children of all ages is recommended by the American Academy of Pediatrics and can be used without causing tooth staining or weakening of tooth enamel.
Prevention of Epidemic Typhus
Measures to control lice can help prevent the infection from spreading. For example, lice-infested clothing and bedding should be washed at least once a week in hot water (over 149° F [over 65° C]) and dried on high heat. Non-washable clothing and items can be dry-cleaned or sealed in a plastic bag and stored for 2 weeks. Bedding and clothing also can be treated with the insecticide permethrin.
People who have a lice infestation may be given malathion (which is a prescription medication) to apply to their skin and eliminate the lice. However, because body lice live in people's clothing and bedding, rather than on their skin (as head and pubic lice do), treatment of clothing and bedding is usually adequate.
People should avoid contact with wild flying squirrels and their nests.
See also Treatment of Lice Infestation.
Brill-Zinsser Disease
Brill-Zinsser disease is a form of epidemic typhus that can reactivate in a person sometimes years or even decades after the first infection.
Some of the organisms that cause epidemic typhus remain in the body. They may become reactivated if a person is under chronic stress or their immune system is weakened. Brill-Zinsser disease most commonly occurs in people who did not receive treatment during the first infection.
Symptoms of Brill-Zinsser Disease
Symptoms are almost always mild and resemble those of epidemic typhus. The fever lasts about 2 weeks. People may not have a rash.
Diagnosis and Treatment of Brill-Zinsser Disease
Diagnosis and treatment are generally similar to those of epidemic typhus.
Drug Information for the Topic
