The seroprevalence of Crimean-Congo haemorrhagic fever among inhabitants living in the endemic regions of Western Anatolia

BACKGROUND: In Turkey, Crimean-Congo haemorrhagic fever (CCHF) is seen particularly in the north-eastern part of Anatolia. Aydin was thought to be a non-endemic area, however the first case was reported from Aydin in 2006 and a total of 39 cases were reported between 2006 and 2010. METHODS: Four hundred and twenty-nine volunteers from 3 endemic regions of Aydin were enrolled in this study. We determined the IgG seropositivity against the virus by enzyme-linked immunosorbent assay (ELISA) method. RESULTS: IgG seropositivity in the study group was found to be 19.6% (n = 84). Chi-squared automatic interaction detector (CHAID) analysis was performed and a significant relationship between IgG seropositivity and tick-bite was found. The IgG seropositivity rate was 13% in cases without a history of tick-bite, while it was 41.1% in those with a tick-bite history (p < 0.001). In cases without a history of tick-bite (n = 339), the most important factor related to seropositivity was cattle-dealing. The seropositivity rate was higher in women than in men in the group dealing with cattle without a history of tick-bite (p = 0.013). In cases with a tick-bite history, the most important factor related to IgG seropositivity was age; the rate was 81% in cases younger than 34 y old, while it was 29% in cases older than 34 y. CONCLUSIONS: This study indicates that people suffering from the disease did not ask for any professional healthcare or that the healthcare providers could not diagnose these cases.