This occurs secondary to the chemicals mentioned above, as well as damage from the infection, and involves signals to immune cells (T cells and macrophages) to come to the site of the infection.Rickettsia bacteria species like R. africae replicate around the area of the initial tick bite, causing necrosis (cell death) and lymph node inflammation. This is the cause of the characteristic eschar. Diagnosis
Many patients with ATBF who live in areas with a high number of infections (Africa and the West Indies) do not visit a doctor, as most patients only have mild symptoms. This disease can, however, cause more serious symptoms in travelers who have never been exposed to the Rickettsia africae bacterium before and are not immune. Travelers who present to a doctor after a trip to affected areas can be hard to diagnose, as many tropical diseases cause a fever similar to that of ATBF. Other diseases that may look similar are malaria, dengue fever, tuberculosis, acute HIV and respiratory infections. In addition to questions about symptoms, doctors will ask patients for an accurate travel history and whether he/she was near animals or ticks. Microbiological tests are available for doctors, but are expensive and often must be done by special laboratories.The antibiotic treatment available for rickettsiae infections has very few side effects, so if a doctor has a high suspicion of the disease, he or she may simply treat without doing more laboratory tests. Blood tests
Diagnosis of ATBF is mostly based on symptoms, as many laboratory tests are not specific for ATBF.
African tick bite fever (ATBF) is a bacterial infection spread by the bite of a tick. Symptoms may include fever, headache, muscle pain, and a rash. At the site of the bite there is typically a red skin sore with a dark center. The onset of symptoms usually occurs 4–10 days after the bite. Complications are rare but may include joint inflammation. Some people do not develop symptoms.Tick bite fever is caused by the bacterium Rickettsia africae. The bacterium is spread by ticks of the Amblyomma type. These generally live in tall grass or bush rather than in cities. The diagnosis is typically based on symptoms. It can be confirmed by culture, PCR, or immunofluorescence.There is no vaccine. Prevention is by avoiding tick bites by covering the skin, using DEET, or using permethrin treated clothing. Evidence regarding treatment, however, is limited. The antibiotic doxycycline appears useful. Chloramphenicol or azithromycin may also be used. The disease will also tend to resolve without treatment.The disease occurs in sub-Saharan Africa, the West Indies, and Oceania. It is relatively common among travelers to sub-Saharan Africa. Most infections occur between November and April. Outbreaks of the disease may occur. The earliest descriptions of the condition are believed to be from 1911. African tick bite fever is a type of spotted fever. It has previously been confused with Mediterranean spotted fever. Signs and symptoms
African tick bite fever is often asymptomatic or mild in clinical presentation and complications are rare.