Crimean-Congo Hemorrhagic Fever in Turkey

OpenAlex İngilizce

In 2002 and 2003, a total of 19 persons in Turkey had suspected cases of Crimean-Congo hemorrhagic fever (CCHF) or a similar viral infection.Six serum samples were tested; all six were found positive for immunoglobulin M antibodies against CCHF virus.Two of the samples yielded CCHF virus isolates.Genetic analysis of the virus isolates showed them to be closely related to isolates from former Yugoslavia and southwestern Russia.These cases are the first of CCHF reported from Turkey.Eighteen patients handled livestock, and one was a nurse with probable nosocomial infection.The case-fatality rate was 20% among confirmed CCHF case-patients (1 of 5 patients), and the overall case-patient fatality rate was 11% (2 of 19 patients).In addition to previously reported symptoms and signs, we report hemophagocytosis in 50% of our patients, which is the first report of this clinical phenomenon associated with CCHF. C rimean-Congo hemorrhagic fever (CCHF) is an acuteillness affecting multiple organ systems and characterized by extensive ecchymosis, visceral bleeding, and hepatic dysfunction; and it has a case-fatality of 8% to 80% (1).CCHF virus (CCHFV) (genus Nairovirus, family Bunyaviridae) is transmitted to humans by bites of infected ticks (several species of genus Hyalomma).CCHFV has also been transmitted to patients or viremic livestock through contact with blood or tissue (1).Epidemics of CCHFV have previously been reported from Eastern Europe, Africa, and central Asia (2-8).Many cases have been reported from the countries around Turkey, including Albania, Iran, Iraq, Russia, and the former Yugoslavia (7,9-12).Although serologic evidence indicated the existence of CCHFV in Turkey several decades ago (13), no clinical cases have been documented.We describe 19 patients from the eastern Black Sea region with hemorrhagic fever compatible with CCHF, who were admitted to Karadeniz Technical University Hospital during the spring and summer of 2002 and 2003. Patients and Methods PatientsSeveral patients in May through July 2002 and 2003 were referred from surrounding county hospitals to our hematology unit with varying degrees of fever and hematologic manifestations.All of the patients had similar clinical and laboratory findings, including fever, petechiae, headache, abdominal pain, nausea, vomiting, liver enzyme elevations, and cytopenia.Bone marrow aspiration and routine serologic tests excluded hematologic malignancies and known viral or bacterial infections.Serum samples from several patients admitted in 2003 were stored at -80°C for further diagnostic testing for a possible hemorrhagic fever agent. Laboratory TestingSerum samples from seven patients were sent to Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA (CDC) for testing.Only six samples from five patients were available in sufficient volume.After we considered possible hemorrhagic fever viruses in the region, we performed immunoglobulin (Ig) M and IgG enzyme-linked immunosorbent assay (ELISA), using inactivated native CCHFV (Strain IbAr 10200) antigens grown in Vero E6 cells on serum samples (14).A test developed to detect CCHF viral antigens was also performed (15).Virus isolation attempts from the serum samples were conducted under biosafety level 4 conditions with Vero E6 cells.For virus genetic detection and analysis, serum samples or infected Vero E6 cells were combined with Tripure Isolation Reagent (Roche Applied Science, Indianapolis, IN) in a ratio of 1:5 and incubated at room temperature for Crimean-Congo Hemorrhagic Fever in Turkey