West Nile and Usutu viruses co-circulation in central Italy: outcomes of the 2018 integrated surveillance

Parasites & Vectors

Francesco Censi¹  Francesca Rosone²  Marcello Giovanni Sala²  Maria Teresa Scicluna²  Pasquale Rombolಠ Adele Magliano²  Ida Ricci²  Gianpaolo Bruni²  Paola Scaramozzino²  Federico Romiti²  Andrea Carvelli²  Giuseppe Manna²  Claudio De Liberato²  Giuseppina Cappiello³  Stefania Vaglio⁴ 

[1] Azienda Sanitaria Locale di Latina, Via Pier Luigi Nervi, Latina Fiori, 04100, Latina, Italy;Istituto Zooprofilattico Sperimentale del Lazio e della Toscana “M. Aleandri”, Via Appia Nuova 1411, 00178, Roma, Italy;Ospedale “S. Pertini”, Via dei Monti Tiburtini 385, 00157, Roma, Italy;Università degli Studi di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185, Roma, Italy;

关键词: Co-circulation;    Culex pipiens;    Italy;    Surveillance;    Usutu virus;    West Nile virus;   

DOI  :  10.1186/s13071-021-04736-z

来源: Springer

【 摘 要 】

BackgroundWest Nile (WNV) and Usutu (USUV) are emerging vector-borne zoonotic flaviviruses. They are antigenically very similar, sharing the same life cycle with birds as amplification host, Culicidae as vector, and man/horse as dead-end host. They can co-circulate in an overlapping geographic range. In Europe, surveillance plans annually detect several outbreaks.MethodsIn Italy, a WNV/USUV surveillance plan is in place through passive and active surveillance. After a 2018 WNV outbreak, a reinforced integrated risk-based surveillance was performed in four municipalities through clinical and serological surveillance in horses, Culicidae catches, and testing on human blood-based products for transfusion.ResultsEight WNV cases in eight equine holdings were detected. Twenty-three mosquitoe catches were performed and 2367 specimens of Culex pipiens caught; 17 pools were USUV positive. A total of 8889 human blood donations were tested, and two asymptomatic donors were USUV positive.ConclusionsDifferent surveillance components simultaneously detected WNV only in horses and USUV only in humans and mosquitoes. While in endemic areas (i.e. northern Italy) entomological surveillance is successfully used as an early detection warning, this method in central Italy seems ineffective. To achieve a high level of sensitivity, the entomological trapping effort should probably exceed a reasonable balance between cost and performance. Besides, WNV/USUV early detection can be addressed by horses and birds. Further research is needed to adapt the surveillance components in different epidemiological contexts.Graphical Abstract

【 授权许可】

CC BY