West Nile virus activity, Europe 2010

On 7 August 2010, the public health authorities in Greece confirmed an outbreak of West Nile virus (WNV) on the Greek mainland. Although WNV had been previously identified in animals, these were the first reports of human cases from Greece [1,2]. Cases were initially confirmed in the region of Central Macedonia (Northern Greece) and its capital, Thessaloniki. Case numbers increased significantly from August, and by 28 September, 261 cases and 32 deaths had been reported [3]. No further cases were reported after 28 September. While most cases were in Central Macedonia, some cases were identified in more southern areas [4]. Most patients (85%) have had neuro-invasive disease. Symptom onset for the first patients was in early July, and cases have presented at an almost constant rate since then. Daily case numbers and weekly epidemiological reports are available from the Hellenic Centre of Control and Prevention of Disease.

In addition, cases were alsoreported in Romania (from districts throughout the country including: Alba, Bucharest, Cluj, Constanta, Dolj, Galati, Mures, Sibiu, and Teleorman), and Hungary (from Budapest and the counties of Pest and Bekes) [5]. Both these countries have had a previous history of West Nile virus activity.

Equine cases were reported [6] during the summer and early Autumn in Italy (91 cases, most in Sicily) and Spain (39 cases in Andalucia). Spain reported a single human case in the same area [7].

Further information
Advice for health professionals who may see possible cases is available on the HPA website. Advice for travellers to risk areas has been produced by the National Travel Health Network and Centre [8]. The European Centre for Disease Control produced a risk assessment for Europe and a mission report for WNV in Greece. 

References

1. ECDC. West Nile virus outbreak in Greece [online]. [Accessed 2 September 2010]. ECDC website: ECDC Portal > English > Activities > Scientific Advice.
2. HPA. West Nile virus in Greece. Health Protection Report 2010; 4(13): Travel Health. Available at: http://www.hpa.org.uk/hpr/archives/2010/hpr3210.pdf.
3. Centre of Control and Prevention of Disease. Athens, Greece. Daily Report of Epidemiological Surveillance of West Nile Virus Infection in Greece. 22 October 2010 [Accessed 15 December 2010] Available at: http://www.keelpno.gr/images/stories/keelpno/ios_ditikou_neilou/wnv_weekly_report_2010_10_22_english.pdf
4. Centre of Control and Prevention of Disease. Athens, Greece. Weekly report 22 October 2010.  [Accessed 15 December 2010]. Available at http://www.keelpno.gr/images/stories/keelpno/ios_ditikou_neilou/report_total_20100917_en.pdf
5. ECDC. West Nile virus transmission in Europe [online]. [Accessed 3 September 2010]. ECDC website: ECDC Portal > English > Activities > Scientific Advice.
6. OIE World Animal Health Information Database [online]. West Nile virus in 2010. [Accessed 15 December 2010].
7. EpiSouth Weekly Bulletin, 30 September 2010. Available at http://www.episouth.org/download.php?&id=12122 
8. National Travel Health Network and Centre. West Nile virus (humans): Greece, Romania, Hungary and the Russian Federation – Clinical Update, 3 September 2010. Available at: http://www.nathnac.org/pro/clinical_updates/westnile_eu_030910.htm.

Last reviewed: 23 August 2011