Epidemiology and clinical features of Mediterranean spotted fever in Italy.

Mediterranean Spotted Fever is caused by Rickettsia conorii and is transmitted to humans by Rhipicephalus sanguineus, the common dog tick. It is characterized by the symptomatologic triad: fever, exanthema and "tache noire", the typical eschar at the site of the tick bite. In Italy the most affected region is Sicily. The seasonal peak of the disease (from June through September) occurs during maximal activity of immature stage ticks. Severe forms of the disease have been reported in 6% of patients, especially adults with one of the following conditions: diabetes, cardiac disease, chronic alcoholism, glucose-6-phosphate dehydrogenase deficiency, end stage kidney disease. The mortality rate may reach 2.5%. Oral or parenteral administration of tetracyclines or chloramphenicol represent the standard treatment. Recent studies indicate that oral clarithromycin and azithromycin could constitute an acceptable alternative for the treatment of the disease in children; furthermore, they could be recommended during pregnancy.