Epidemic Typhus: A Disease Spread by Body Lice

Epidemic typhus, or louse-borne typhus, is caused by the bacterium Rickettsia prowazekii and spreads to people through contact with infected body lice. It killed millions in earlier centuries but is now rare. Cases still occur now and then where overcrowding is extreme and lice can pass from person to person.

In the United States, rare cases called sylvatic typhus occur in people exposed to flying squirrels and their nests.

Pediculus humanus corporis, the human body louse. CDC.

Signs and symptoms

Symptoms begin within 2 weeks of contact with infected lice and may include:

• fever and chills
• headache
• rapid breathing
• body and muscle aches
• rash
• cough
• nausea and vomiting
• confusion

Brill-Zinsser disease. Some people stay infected, without symptoms, for years after their first illness. Rarely, they relapse months or years later, usually when the immune system is weakened by certain medicines, old age or illness. The relapse resembles the first illness but is usually milder.

Prevention

There is no vaccine. Body lice thrive where people are crowded together and cannot bathe or change clothes regularly. To avoid them:

• bathe regularly and put on clean clothes at least once a week;
• wash infested clothing at least once a week, machine-washing clothes and bedding in hot water (at least 130°F) and drying them on high heat when possible;
• dry-clean clothing and items that cannot be washed, or seal them in a plastic bag for 2 weeks;
• do not share clothing, beds, bedding or towels with anyone who has body lice or typhus;
• treat bedding, uniforms and other clothing with 0.5% permethrin, which kills lice and can protect clothing through many washes; follow the product's instructions, and never put permethrin products on skin;
• avoid contact with flying squirrels and their nests.

Testing and treatment

The symptoms resemble those of many other diseases. See a healthcare provider if they appear after travel or contact with animals, and mention any contact with flying squirrels or their nests. A blood test looks for epidemic typhus and other diseases; results can take several weeks, so treatment may start before they arrive.

The treatment is the antibiotic doxycycline, which can be given at any age. Antibiotics work best soon after symptoms begin, and people treated early with doxycycline usually recover quickly.

Sources

• Centers for Disease Control and Prevention, "About Epidemic Typhus." https://www.cdc.gov/typhus/about/epidemic.html
• A photograph of a southern flying squirrel, uncredited on CDC's page, is not reproduced here.