Flea-borne Typhus

Typhus can be carried by opossums and cats, and several species of rodents including rats and mice.

There are two natural cycles of flea-borne typhus. One involves opossums and possibly feral cats that are natural reservoirs (animals that both maintain and transmit the disease organism) for endemic typhus. The cat flea, Ctenocephalides felis, is the vector (animals that transfer the disease from one host to another) of endemic typhus. Another cycle involves rats and rat fleas. In Orange County, recent cases of typhus are most likely due to an opossum, cat, and cat flea cycle.

Since the disease is spread by fleas, it is possible that endemic typhus could be transmitted year round.

People get flea-borne typhus from an infected flea. Most fleas defecate while biting; the feces of infected fleas contain the bacteria that cause the disease. The bacteria enter the body at the time of the bite wound or from scratching of the bite area. It is possible to get typhus by inhaling contaminated, dried flea feces. However, this method of transmission is not as common as transmission from a biting flea.

Typhus is not transmitted from person-to-person.

All residents of areas where endemic typhus activity has been identified are at risk of getting the disease. Older people have the highest risk of severe disease.

Symptoms of typhus most commonly include:

• Fever
• Headache
• Rash (may start several days after initial symptoms)
• Muscle aches

Some people may have:

• Nausea
• Vomiting
• Dry cough
• Abdominal pain

The incubation period for typhus is 6 to 14 days. If you suspect that you have typhus, see a physician as soon as possible.

A physician must order blood tests to tell you if you have typhus.

This disease is treatable with physician prescribed antibiotics.

• Keep domestic animals free of fleas by regularly treating them with flea prevention medications. Consult your veterinarian for more information
• Keep the area around your home or business free of fleas. Consult a licensed pest management company for additional information
• Trim heavy vegetation such as ivy and ground cover which provide harborage for wild animals
• Seal off openings to attics, crawl spaces, floors, and similar locations so animals cannot gain entrance to houses and other structures
• Keep trash cans covered at all times
• Do not encourage animals to visit your home by directly or indirectly feeding them. Remove fruit that has dropped from trees, uneaten pet food, open trashcans, and bird feeders where it may attract other animals

About one percent of cases may result in death.

There is no vaccine against typhus available in the U.S.

Reservoir hosts of Rickettsia typhi typically show no signs of the infection.

For more information on flea-borne typhus, check our

Orange County Epidemiology Web page on typhus.