Thoughout the centuries, ticks and fleas have been carriers for a host of serious diseases from Lyme's disease to the Bubonic plague. One such illness, African tick-bite fever, or rickettsia africae, has not claimed any lives, according to the American Society for Microbiology. This disease, which once affected only those of the western, central and southern African regions, according to the U.S. Centers for Disease Control and Prevention, is increasingly spreading to other regions due to a rise in tourist travel to endemic locations. The American Society for Microbiology states that the first documented case in a human was in 1992, so it is a relatively new form of tick disease.
How It's Spread
This disease is caused by gram-negative bacteria that are spread from animals to humans through the bite of a species of tick known as the Amblyomma variegatum. The preferred hosts for the tick are farm animals, but they will bite humans occasionally. The CDC states that tick-bite fever is the second most identified cause for febrile illnesses in sub-Sahara Africa travelers. The only more common febrile illness for visitors to these areas is malaria.
Amblyomma Variegatum
The Center for Food Security and Public Health in Iowa released a report about these species of tick in September 2009. It describes these ticks as hard-shelled with large mouth parts that make a bite severely painful. A large wound is left from the bite of the tick and additionally the large mouth parts make the tick particularly hard to remove. Since the bite is so large, a secondary infection in the bite wound can develop as well as disease. While the R africae disease is the most common disease this tick carries, the CDC states they also can transmit Crimean-Congo hemorrhagic fever virus, Dugbe virus, Thogoto virus, Bhanja virus, Ehrlichia ruminantium, Theileria spp., Anaplasma spp., and Dermatophilus congolensis.
Symptoms
The symptoms from African tick disease are fairly mild as the most commonly reported symptoms are those of a febrile illness, which includes a quick onset of chills, shivers and fever. Other reported symptoms include the formation of eschars on the skin. Eschars are a type of scab that typically develop after a thermal burn. In this type of infection, however, the scab forms over the bite wound. These symptoms can appear one to two weeks after a bite, according to the CDC.
Testing
The CDC states there are several forms of blood tests that look for African tick disease antibodies. Additionally the lab can try to obtain the bacteria from blood or by swabbing the wounds to culture and identify the bacteria directly.
Treatment
Since African tick bite fever is caused by a bacterium, certain antibiotics work well to rid the body of infection. The CDC states the specific antibiotics used are tetracycline class drugs, or doxycycline, for a period of three to 14 days depending on the patient's age and severity of the disease.
