Preliminary characterization and natural history of hantaviruses in rodents in northern Greece.

To the Editor: Hantaviruses (family Bunyaviridae), cause hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia and hantavirus pulmonary syndrome in the Ameri-cas. In Greece, hantaviruses are endemic, and small outbreaks or sporadic cases of HFRS have been observed; Dobrava virus is the predominant hantavirus and causes severe HFRS (1,2), while Puumala virus is probably the causative agent of the milder forms of this syndrome (Papa et al., unpub. data). Hantaan virus, associated with Apodemus agrarius, and Seoul virus, associated with Rattus norvegicus, have never been detected in Greece. Dobrava virus is hosted by A. flavicollis in the Balkans (3,4) or by A. agrarius in northern Europe (5). We surveyed two sites where Dobrava virus-caused HFRS was reported (2). The first was Nevrokopi, a small town in the Rhodope Mountains, 12 km from the Greek-Bulgarian border (41° 20.184' N, 23° 49.479' E, elevation approximately 650 m). The second site included Pramanta, a small village in the Pindos Mountains , approximately 67 km southeast of Ioannina (39° 31.722' N, 21° 5.872' E, elevation 790 m), and Matsuki, a small village near Pramanta (39° 33.909' N, 21° 9.713' E, elevation 1080 m). Animals were trapped and sampled outdoors according to established safety guidelines (6). Blood, lung, kidney, and spleen samples were kept in liquid nitrogen until transferred to-70°C freezers for storage. At Nevrokopi, 57 small mammals were captured during 887 trap nights for an overall trap success rate of 6.4%. At Pramanta and Matsuki, 13 small mammals were captured during 400 trap nights (3.3% trap success). The total of 70 captured mammals comprised seven species of rodents and one insectivore. A. flavicollis was the most commonly captured species (87% of captures). Whole-blood specimens were tested for hantavirus immunoglobulin G by indirect immunofluorescence assay and enzyme-linked immunosorbent assay, using Hantaan 76-118 as antigen. Total RNA was extracted from homogenized tissues, and nested reverse transcriptase-polymerase chain reaction (PCR) was performed with two sets of nested primers (2): one set designed to detect the partial G1 coding region of hantaviruses associated with rodents of the subfamily Murinae (Hantaan, Dobrava, and Seoul viruses), and another to detect the N coding region of hantaviruses associated with rodents of the subfamily Arvicolinae (Prospect Hill virus). Eight A. flavicollis, all from Nevrokopi, were positive for hantavirus infection by serology or molecular methods, for a 13% overall prevalence in A. flavicollis. Some rodents positive by serology were negative by …