Relapsing Fever

Relapsing fever is an acute infection caused by Borrelia species, characterized by paroxysmal high fever, generalized pain, hepatosplenomegaly; severe cases have jaundice/bleeding. Fever and afebrile intervals alternate. Two types: louse-borne (epidemic) and tick-borne (endemic).

Common Symptoms

Hepatosplenomegaly; Yi Yupin; ecchymosis; chills; gingival bleeding; dizziness; confusion; fatigue; nausea

Causes and Pathogenesis

(1) Etiology: Borrelia. Louse-borne epidemic = B. recurrentis (obermeieri). Tick-borne endemic species named after Ornithodorus soft ticks: B. persica (Persia), B. latyschevi (Xinjiang), B. duttoni (Central Africa), B. hermsii (western USA); 9 serotypes of B. duttoni in India. Recently flagellin-gene probes identified B. parkeri/turicatae/crocidurae/anserina/coriaceae. Borrelia are 10-20 × 0.3-0.5 µm with 4-10 irregular coils, binary fission; heat/dry/disinfectant-sensitive but cold-resistant (100 days in clotted blood at 0°C). Have specific/non-specific antigens; Weil-Felix OXk agglutination weak. Antigenic variation is key. (2) Pathogenesis: fever reflects rapid spirochetemia and toxins; IgM/IgG antibodies (agglutinins/immobilisins/lysins) clear spirochetes → defervescence. Survivors hide in brain/liver/spleen/bone marrow; antigenic evasion causes relapse. Endothelium/platelet/RBC damage → anemia/bleeding/jaundice; neuro-ophthalmic involvement. Pathology: splenomegaly with infarcts/abscesses/rupture; liver necrosis/hemorrhage/cloudy swelling; kidney congestion; myocarditis; cerebral edema/hemorrhage.

Treatment

Drug therapy, supportive therapy

Preventive Measures

Cut transmission; control reservoirs. No effective vaccine. (1) Isolate patients and delouse; rodent/tick control for endemic form. (2) Kill ticks/lice; insecticide on ground/corners/roadsides. (3) Personal protection: protective clothing; doxycycline/tetracycline prophylaxis.

Department to Visit

It is recommended to visit the Infectious Diseases department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.