Usutu virus (USUV) is a mosquito-borne virus belonging to the family Flaviviridae, genus Flavivirus. Natural transmission cycle of USUV involves mosquitoes and birds, so humans and other mammals are considered incidental hosts. In this study, USUV infection was diagnosed in all wild blackbirds, collected from July to September 2018 in a wildlife recovery center in the province of Bologna, in the Emilia-Romagna region, northern Italy. All blackbirds showed neurological clinical signs, such as overturning, pedaling, and incoordination. Moreover, the subjects died shortly after arriving at the hospitalization center. Virological investigations were performed by real-time PCR on frozen samples of the spleen, kidney, myocardium, and brain for the detection of Usutu (USUV) and West Nile (WNV) viruses. The small and large intestine were used as a matrix for the detection of Newcastle disease virus (NDV). All 56 subjects with neurological clinical signs were positive for USUV, only one subject (1.8%) tested positive for WNV, and no subject was positive for NDV. The most represented age class was class 1 J (58.9%), followed by class 3 (25.0%), and lastly from class 4 (16.1%). Most of the blackbirds before dying were in good (51.8%) and fair (39.3%) nutritional status, while only five subjects (8.9%) were cachectic. The USUV genomes detected in the blackbirds of this study fall within the sub-clade already called EU2 that has been detected since 2009 in the Emilia-Romagna region. Neurological clinical signs in USUV-affected blackbirds are still widely discussed and there are few works in the literature. Although our results require further studies, we believe them to be useful for understanding the clinical signs of Usutu virus in blackbirds, helping to increase the knowledge of this zoonotic agent in wild species and to understand its effect on the ecosystem. The goal of this study was to report—in the context of the regional passive surveillance program—the detection of USUV RNA in its most important amplifying host, the common blackbird, when showing clinical signs before death.

The number of newly described sandfly-borne phleboviruses has been steadily growing in recent years. Some phleboviruses are human pathogens, but their health relevance is largely uncharacterized. We aimed to investigate the circulation of these viruses in the Emilia-Romagna region where several have already been described. A total of 482 sandflies were collected in a site in Reggio Emilia in 2019 and 2020. Sandflies collected in 2020 were grouped in 21 pools with a maximum of 25 sandflies per pool, submitted to real time PCR, and isolated in Vero cell culture. Complete genome sequencing showed the isolation of a strain of a Ponticelli III virus. This virus, which belongs to the species Adana phlebovirus, differed in the M segment from the Ponticelli I and Ponticelli II viruses. Analysis performed on the genomic segments of the newly isolated virus compared with other phleboviruses highlighted a strong purifying selection in the L segments, and different substitution saturation, highest in the M segments. Future research should address the ecological processes driving the occurrence of these novel phleboviruses and their possible impact on public health.