An outbreak of Crimean-Congo hemorrhagic fever in western Anatolia, Turkey

Abstract

Sporadic Crimean-Congo hemorrhagic fever (CCHF) cases were first reported in Turkey in 2002, arising particularly in northeastern Anatolia. Epidemics have been reported in neighboring countries since the 1970s. With the increase in number of CCHF virus infected or suspected cases in the Aydin region of western Anatolia by 2006, we decided to focus attention on this disease. Twenty-six patients with an acute febrile syndrome characterized by malaise, bleeding, leukopenia, and thrombocytopenia were admitted to various hospitals in Aydin between May 2007 and June 2008. CCHF diagnosis was established by measuring IgM in a blood sample and/or detecting viral genome by real-time polymerase chain reaction (real-time PCR) or by clinical findings of the disease, even if IgM was negative (real-time PCR was not performed). Twenty-five patients (22 of the patients with cases confirmed by laboratory findings) matched the criteria for CCHF defined by the European Network for Diagnostics of 'Imported' Viral Diseases (ENIVD); one patient did not match suspected-case criteria, however he was also included in the study as his blood sample was positive according to real-time PCR. The most common signs and symptoms encountered were fever, myalgia, nausea, and vomiting. The overall case-fatality rate was 5.5% (one patient) in 2007. Patients showed hemorrhagic manifestations (35%), while complete blood counts revealed thrombocytopenia and leukopenia in 17 patients (65%), and raised levels of aspartate aminotransferase (77%), alanine aminotransferase (77%), lactate dehydrogenase (69%), and creatinine phosphokinase (42%). To date, western Anatolia has been accepted as a non-endemic area for this disease, with only sporadic cases. These non-endemic CCHF cases in Aydin province of the Aegean region should alert other non-endemic regions of the world to be mindful of this disease.