Mosquitoborne viruses, Czech Republic, 2002

Abstract

Specimens from residents (N = 497) of an area affected by the 2002 flood were examined serologically for mosquitoborne viruses. Antibodies were detected against Tahyna (16%), Sindbis (1%), and Batai (0.2%) viruses, but not West Nile virus. An examination of paired serum samples showed 1 Tahyna bunyavirus (California group) infection.

Figure 1

A), Potential foci of mosquitoborne viruses in the Mělník area. Floodplain forests identified on the Landsat MSS satellite images (dotted red line), with hydrology and settlement in background (DMU-200, VTOPÚ Dobruška), and proportion of Tahya virus seropositive residents at particular localities (large, medium, and small circles indicate the risk zones A, B, and C, respectively). B) [inset], radar satellite image of the conflux of the Labe and Vltava Rivers on August 17, 2002 (2 days after the flood culmination), showing extent of floodwater (dark areas). Inundated forests, with subsequent mass occurrences of Ochlerotatus and Aedes mosquitoes, are visible as lighter areas surrounding Labe River upstream of the confluence; scattered lagoons (dark areas) in arable fields along both rivers far left and right turned into breeding sites of predominantly Culex mosquitoes.

Figure 2

Distribution of 50% plaque-reduction neutralization titers of antibodies to Tahyna virus (y axis, number of seroreactors).