Relapsing fever, endemic A68.1

Borrelia spp.

• B. duttonii and B. crocidurae (Africa)
• B. hermsii, B. turicatae, B. parkeri (North America)
• B. venuzulensis, B. neotropica (Central and South America)
• B. persica (Middle East, Asia)
• B. hispanica (Iberian Peninsula, North Africa)

Pathogen reservoir: human (Africa), tick, rodent, poultry, dogs, wild boar.

Carrier: leather tick (Ornithodorus moubata).

Tropical Africa, Spain, North Africa, Arabian Peninsula, Middle East, South and Central Asia, North and South America. In Central Europe relapsing fever is very rare. If it occurs, it is usually a travel sickness or infected migrants from North East Africa.

Incubation period 5-15 days. At the puncture site, occasionally an ulcerated nodule up to the size of a pea can be detected, which can be covered with black crusts (Tache noir). Massive bacteremia and infestation of almost all organs. The degree of spirochaemia determines the clinical severity. In contrast to malaria, fever attacks last 2-4 days and are interrupted by fever-free 3-6-day intervals. The fever-free intervals increase in duration as the disease progresses. Relapses occur about 2-10 times, whereby the severity of the disease decreases. Immunity up to 1 year after infection. The most frequent cause of death is myocarditis.

Characteristic (in about 60% of infected persons) is a stem-emphasized, small macular or small papular, petechial exanthema (tendency to bleed) towards the end of the first fever period. Damage to the vascular endothelium, bleeding tendency and organ necrosis determine the course of the disease. The skin changes do not occur after the first period.

Complications include a strong tendency to bleed (epistaxis, conjunctival bleeding, haemorrhages of the gastrointestinal tract, lungs, urinary tract and CNS), nephritis, liver failure, myocarditis, sepsis with disseminated intravascular coagulation.

Pathogen detection in the blood (smear, thick drop, dark field microscopy). Serology (ELISA, CFT, agglutination). If necessary, detection in animal experiments. A cultural cultivation of Borrelia bacteria is possible under special culture conditions.

Blood count: neutrophil leukocytosis, inflammation parameters significantly increased.

Doxycycline (e.g. Doxycycline Heumann) 2 times/day 100 mg p.o. or tetracycline (e.g. Tetracycline Wolff) 3-4 times/day 500 mg p.o. for 14 days. Infants should receive penicillin instead of tetracycline.

Caution: Jarisch-Herxheimer reaction

1. Bissett JD et al (2018) Detection of Tickborne Relapsing Fever Spirochete, Austin, Texas, USA. Emerg Infect Dis 24:2003-2009.
2. Mafi N et al (2019) Tick-Borne Relapsing Fever in the White Mountains, Arizona, USA, 2013-2018. Emerg Infect Dis 25:649-653.
3. Naddaf SR et al. (2015) Tickborne relapsing fever in southern Iran, 2011-2013. Emerg Infect Dis 21:1078-1080 .