relapsing fever, any one of several acute infectious diseases marked by recurrent febrile episodes, caused by various strains of the spirochete Borrelia. The disease is transmitted by both lice and ticks and is often seen during wars and famines. It has occurred in several western states of the United States but is more commonly found in South America, Asia, and Africa. See also African tick fever. ▪ OBSERVATIONS: The first episode usually starts with a sudden high fever (104° F to 105° F, or 40° C to 40.56° C), accompanied by chills, headache, neuromuscular pains, and nausea. A rash may appear over the trunk and extremities, and jaundice is common during the later stages. Each attack lasts 2 or 3 days and culminates in a crisis of high fever, profuse sweating, and a rise in heart and respiratory rate. This is followed by an abrupt drop in temperature and a return to normal blood pressure. ▪ INTERVENTIONS: Penicillins and tetracycline have been the treatment of choice in relapsing fever. A number of other antibiotics are also employed. Other interventions are supportive. ▪ PATIENT CARE CONSIDERATIONS: People typically relapse after 7 to 10 days of normal temperature. Mortality rates can be high; however, survivors eventually recover completely. In louse-borne disease there is usually only a single relapse; in tick-borne disease several successively milder relapses may occur.
