Rickettsia conorii, transmitted by the brown dog tick Rhipicephalus sanguineus, is the causative agent of Mediterranean spotted fever (MSF). Rickettsia conorii is a member of the spotted fever group. MSF is also known as boutonneuse fever, Marseilles fever, Kenya tick typhus, and Indian tick typhus.

MSF is most commonly noted in northern and sub-Saharan Africa as well as southern Europe, but it has been reported in Eastern Europe too. In temperate climates, the frequency of infection increases in the summer months.

Patients with MSF present with diffuse rash and fever, which may be accompanied by other less common symptoms, including headache (56%), arthralgias, and myalgias. Serious complications include meningoencephalitis, vasculitis, and deep vein thrombosis (DVT).

Contact with dogs increases the likelihood of contracting MSF. Male adults and children are more commonly infected. Disease transmission to travelers who visit endemic areas has been well documented.

More severe disease has been noted in those who abuse alcohol, individuals with diabetes, the elderly, and those with glucose-6-phosphate dehydrogenase (G-6PD) deficiency. MSF is not often fatal except in elderly patients.