Investigation of the Presence of Crimean-Congo Hemorrhagic Fever Virus RNA in Tears of Eleven Infected Patients

Abstract

Purpose: To investigate the presence of viral RNA in tears of patients with Crimean-Congo hemorrhagic fever (CCHF) disease. Methods: This study was conducted on eleven patients with CCHF cases. The diagnosis of CCHF was based on clinical and epidemiological findings and the detection of CCHF virus (CCHFV)-specific IgM and of CCHFV RNA in the serum samples of the patients by ELISA and a real time reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. CCHFV RNA positive patients tear samples were then subjected for investigation of viral RNA. Blood and tears of patients were collected at the same time within 24 hours of hospitalization of patients. A TaqMan-based onestep real time RT-PCR was applied to detect CCHFV RNA in sera and tears of patients. Results: Eight patients were male and three patients were female. One of 11 patients had only CCHF virus-specific IgM antibodies and four of 11 patients' blood sera had only positive for viral RNA. Both viral RNA and virus specific IgM were detected in six out of eleven patients' sera. Although the presence of CCHFV RNA was confirmed in 10 (90.9%) patients' sera, none of the patients' tear had viral RNA. Conclusions: The preliminary results obtained in the present study showed that the presence of CCHFV RNA was not detected in tear fluids in patients having CCHF disease. This suggested that tears of CCHF patients may not have a potential for CCHFV virus transmission.