Rapid risk assessment: Review of the epidemiological situation of West Nile virus infection in the European Union

risk assessment

In the ongoing 2011 West Nile virus transmission season, cases have been reported from newly affected geographical areas. This was not entirely unexpected since areas with favourable ecological parameters for the interaction between migratory birds, resident birds, competent mosquito vectors and humans are known to be at risk for the establishment of active and efficient transmission of the virus to humans. Further geographical extension of affected areas is therefore likely in the coming years.
Multi-sectoral collaboration and intensified surveillance made it possible to detect West Nile virus in new areas and identify WNV lineage 1 and lineage 2, which are now both circulating in Europe.
EU Member States are responding to this situation with the implementation of preventive measures, including the safeguarding of blood supplies. However, important gaps remain in our current knowledge of West Nile virus epidemiology, and further research and studies are needed in this context.

Executive summary

86 human cases of West Nile fever have been reported in the EU, with 74 cases in Greece, eight in Romania, and four cases in Italy. In the neighbouring countries, 125 cases have been declared.

West Nile virus transmission is now established in several European countries and its further spread is expected in the coming years. Multi-sectoral collaboration and intensified surveillance made it possible to detect West Nile virus in new areas and identify WNV lineage 1 and lineage 2, which are now both circulating in Europe.

EU Member States are responding to this situation with the implementation of preventive measures, particularly the safeguarding of blood supplies. In addition, efforts should be made to further strengthen laboratory capacity for reliable WN diagnosis, fostering collaboration between public health and veterinary authorities and to increase our current knowledge of the disease.

Download