Oroya fever

**Definition:** A disease commonly caused by an infection with the gram-negative bacteria Bartonella bacilliformis. This disease is characterised by severe haemolytic anaemia and transient immunosuppression. This disease may present with fever, malaise, or jaundice. Transmission is through the bite of infected sandflies from the genus Lutzomyia. Confirmation is by identification of Bartonella bacilliformis in a blood sample.

**Long definition:** Oroya fever is a bacteraemic form of infection with Bartonella bacilliformis. Transmission is by bite from an infected Lutzomyia sand-fly, a type found only in the high Andes (>1000 metres). There is an incubation period of 3-12 weeks. The illness may range from mild to very severe. In severe cases, fever, chills, headache, sweating, aches, dyspnoea, confusion and seizures may occur.