A novel AP92-like Crimean-Congo hemorrhagic fever virus strain, Greece.

Ticks were collected from various regions of northern Greece and tested for the presence of Crimean-Congo hemorrhagic fever virus (CCHFV) RNA. Human and animal sera were collected in the regions where CCHFV-positive ticks were detected, and they were tested for the presence of IgG antibodies against the virus. A CCHFV strain was detected in Rhipicephalus bursa ticks collected from sheep in Kastoria regional unit, differing by 9.7% at the nucleotide level from the AP92 strain, which was isolated in 1975 in another region of Greece. Up to date, CCHF cases have not been reported in these regions. The human seroprevalence in the area was estimated at 6%, while IgG-positive sheep was detected in two of the four neighboring farms tested. The circulation of this specific CCHFV lineage in Greece, especially in a region where the seroprevalence is high, together with the lack of human CCHF cases, suggests a probable antigenic, but non- or low-pathogenic character of this lineage. Further studies on these strains will increase our knowledge about the role of AP92-like strains in the CCHF epidemiology, which might be useful for drug and vaccine design.