Rickettsia is a type of bacteria that is found around the world. These small, rod-shaped microbes are spread by ticks and mites, and can cause a range of serious illnesses in humans. The most common types of rickettsial infections include: Rocky Mountain spotted fever, typhus, and rickettsialpox. In humans, symptoms of rickettsial infections can include fever, headache, rash, and muscle pain. Diagnosis of a rickettsial infection can be made based on a positive blood test for antibodies specific to the particular type of virus. Treatment usually involves antibiotics, and can involve hospitalization. Rickettsia can also be found in wild and domestic animals, and can cause a range of symptoms depending on the type. Treatment of rickettsial infections in animals can include antibiotics and supportive care, but the prognosis is variable depending on the type of infection. Prevention is the key to avoiding rickettsial infections. This includes avoiding tick and mite bites, and using appropriate tick repellants and protective clothing when in endemic areas. Routine screening of companion animals can help to catch any infections early, before they become severe or spread to humans. Vaccines are available for some rickettsial infections, and may be recommended by a veterinarian.