African Tick Bite Fever

What is African Tick Bite Fever?

African Tick Bite Fever (ATBF) is a bacterial infection caused by the bite of an infected tick. It was first discovered in 1930, however it was not until 1992 that the agent of the disease, the Rickettsia africae bacterium, was isolated. It is estimated that approximately 4-5% of European travelers returning from sub-Saharan Africa and the West Indies, the regions where ATBF is endemic, become infected with ATBF.

How do you get African Tick Bite Fever?

ATBF is contracted through the bite of an infected tick. Ticks carrying the bacteria for ATBF live primarily on cattle but also on livestock and game animals in sub-Saharan Africa and the West Indies. It is estimated that approximately 50% of ticks living on cattle, livestock and game animals carry the bacteria for ATBF.

Susceptibility and Resistance

Those travelling to the regions of sub-Saharan Africa and the West Indies are at greatest risk of contracting ATBF. Although all persons are susceptible, travellers engaging in outdoor activities in these regions (camping, farming, hiking, hunting, visiting game reserves, etc.) will be at higher risk of infection.

ATBF occurs most commonly from November to April when the ticks carrying the disease are most active.

Incubation Period

The incubation period for African Tick Bite Fever is 5-10 days.

What are the Symptoms?

Symptoms of ATBF include fever, headache, muscle pain and soreness, chills and a rash. The site of the bite(s) may be sore and red in colour with a dark, scabby center. Some people may have no symptoms of infection.

The symptoms of ATBF may appear quite similar to the symptoms of Mediterranean Spotted Fever, however they are typically milder.

Rare symptoms such as inflammation of the lymph nodes, brain and heart have also been reported.

Preventative Measures

The primary prevention measure against ATBF is protection against tick bites. Avoid areas with high brush and dense woodlands. Use insect repellent containing at least 20 percent DEET and repeat application of repellent throughout the day. Always wear protective clothing to cover exposed skin, use screens and bed nets and, when possible, use permethrin treated clothing/gear. Upon returning indoors, bathe and check your body, clothing and gear for ticks. Remove any ticks immediately.

No vaccine is available.

Treatment

The patient should seek medical attention when they suspect that they have been in contact with a tick, find a tick on their body or as soon as symptoms appear.

Doxycycline is the recommended antibiotic for the treatment of ATBF and should be the first treatment given to patients suspected to have contracted ATBF. With doxycycline treatment, symptom relief should be noted within 48 hours. Generally, doxycycline treatment lasts 5-10 days. Tetracycline treatment may also be recommended by medical professionals.

Medications

Where Does It Commonly Occur?

ATBF is endemic in sub-Saharan Africa and the West Indies particularly in rural areas where infected ticks, and the animals on which they live, are more widespread.