Investigation of Hantavirus Infections among Cchfv Negative Cases in the Western Black Sea Region of Turkey

Objective: The Hantaviruses and Crimean Congo hemorrhagic fever virus (CCHFV) are members of the Bunyaviridae family. Hantavirus infections causes two main febrile diseases: hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). Hantaviruses are transmitted by rodents. In 2009, a hantavirus outbreak occurred in the Western Black Sea region of Turkey. For the last 10 years, the prevalence of CCHFV has also been high in this region. Methods: We screened patients’ samples for the presence of hantavirus IgM and IgG using ELISA on 42 clinically suspect CCHF cases which were CCHFV real-time-RT-PCR and anti-CCHFV IgM negative without a tick-bite history. The current study was carried out on samples sent between March and September of 2008. SELISA-seropositivity was further evaluated using immunofluorescence assay, immunblotting, and FRNT (focus reduction neutralization test). Real-time-PCR was performed to genotype the seropositive cases. Results: Anti-Hantavirus IgM and IgG positivity were detected in 3 samples (7.1%) by ELISA and immunoblotting tests. Two had a 1:640 titer against Puumala virus (PUUV) strain by FRNT, while all three samples were found negative for Dobrova virus (DOBV). Thus, hantavirus-specific antibodies could be confirmed detected in 2 out of 42 sera (4.8%) by FRNT. Conclusions: TThe authors postulate that Hantavirus infection should be taken into consideration in patients with clinically suspected CCHFV infection. This study also shows that Hantavirus was circulating in the area before the 2009 hantavirus outbreak in the Western Black Sea region of Turkey.