Retrospective identification of human cases of West Nile virus infection in Austria (2009 to 2010) by serological differentiation from Usutu and other flavivirus infections

Abstract

human WNV infections have not previously been documented, although the virus was isolated from birds and detected in mosquitoes in 2008 and 2009. We therefore conducted a retrospective search for human cases of WNV infection using serum and cerebrospinal fluid samples collected from patients with central nervous system (CNS) disease in the summers of 2009, 2010 and 2011. Although all samples were negative for WNV by polymerase chain reaction, quantitative evaluation of standardised antibody assays with purified flavivirus antigens (including Usutu virus, which cross-reacts with WNV even in neutralisation assays) provided serological evidence for three autochthonous WNV infections in Austria: two in 2009 and one in 2010. Our data highlight the importance of raising awareness of WNV infections in Austria and neighbouring countries and suggest including testing for this infection in routine diagnostic practice of CNS diseases.

Influence of flavivirus co‐circulation in serological diagnostics and surveillance: A model of study using West Nile, Usutu and Bagaza viruses

“…Our results confirm that VNT performed in parallel with co‐circulating flaviviruses is more specific than the ELISA tests for WNV antibody detection, supporting the usefulness of this technique as confirmatory method. Furthermore, this study corroborates that cross‐reactions in serological diagnostic methods (including VNT) exist not only between flaviviruses within the same serocomplex (WNV and USUV), but also from different serocomplexes (WNV/USUV and BAGV), as previously observed with other flaviviruses such as Japanese encephalitis virus and tick‐borne encephalitis virus (Klaus, Ziegler, Kalthoff, Hoffmann, & Beer, ; Stiasny, Aberle, & Heinzl, ). These observations may also be relevant when it comes to human diagnosis in areas with co‐circulation of WNV and other flaviviruses such as yellow fever, Japanese encephalitis, zika, dengue or tick‐borne encephalitis viruses in travellers that have visited endemic countries and in people vaccinated against some of these viruses.…”

Short Communication: West Nile fever imported from Austria to Germany

“…Accordingly, WNV RNA was not detected in the present patients’ sera. The enhanced neutralization capability of WNV2 of the patient's sera in VNT suggests WNV2 rather than WNV1 infection of the young woman, in agreement with WNV2 detections in humans, birds, and mosquitoes’ larvae and pupae from Vienna area (Jungbauer et al., ; Kolodziejek et al., ; Stiasny, Aberle, & Heinz, ; Wodak et al., ).…”

“…Accordingly, WNV RNA was not detected in the present patients' sera. The enhanced neutralization capability of WNV2 of the patient's sera in VNT suggests WNV2 rather than WNV1 infection of the young woman, in agreement with WNV2 detections in humans, birds, and mosquitoes' larvae and pupae from Vienna area Kolodziejek et al, 2015;Stiasny, Aberle, & Heinz, 2013;Wodak et al, 2011). Therefore, it is important to consider and include WNV infection in the differential diagnosis for all febrile patients and those with neurological signs with a history of recent travel to endemic areas.…”

Flavivirus Seroepidemiology in Blood Donors in Mersin Province, Turkey

“…Bununla birlikte serolojik yöntemler, fl avivirus enfeksiyonlarının tanısında en sık kullanılan yaklaşımdır 20,21 . Klinik olgularda viremi süre-sinin görece olarak kısa, virus yükünün ise düşük olması nedeniyle laboratuvar tanısında genellikle özgül antikorların tespit edilmesi yaklaşımı tercih edilmektedir 22 . Flavivirus enfeksiyonlarının serolojik tanısında; hemaglütinasyon inhibisyon testi (HI), ELISA ve IIFT gibi birçok yöntem uygulanmaktadır 23 .…”