Project description:Toscana virus (TOSV) is an arthropod-borne virus belonging to the sandfly fever Naples virus species within the genus Phlebovirus. We report here the complete coding sequences of three TOSV strains belonging to lineage B and isolated from sandflies trapped in the Southeast of France between 2009 and 2013.
Project description:BackgroundOur aim is to detect the infection by Toscana virus (TOSV) and other Phleboviruses in the sera and cerebro-spinal fluid (CSF) of patients with meningitis in Tunisia. We examined various species of phlebotomus present in Tunisia to determine whether or not a direct relationship exists between cases of meningitis and the viruses circulating in the insect vectors.MethodsPatients with the meningeal syndrome were tested for anti-TOSV IgM and IgG using an indirect Enzyme-Linked Immunosorbent Assay (ELISA) and for the presence of TOSV and other Phleboviruses using a RT-PCR test.ResultsOf 263 patients were tested using ELISA of which 12.16% (n = 32/263) were IgM positive for anti TOSV. Of these 32 patients, 78% (n = 25/32) were IgG positive. 12.86% (n = 18/140) of the CSF samples tested by RT-PCR were positive for the Toscana virus.ConclusionsThis study confirms, for the first time, that TOSV is involved in a neurological disorder in North Africa. The incidence of this involvement in Tunisia conforms with observations made in other Mediterranean countries. Moreover, for the first time, a molecular approach was used to detect SFSV in a Tunisian patient displaying neurological symptoms.
Project description:Sandflies are widely distributed around the Mediterranean Basin. Therefore, human populations in this area are potentially exposed to sandfly-transmitted diseases, including those caused by phleboviruses. Whilst there are substantial data in countries located in the northern part of the Mediterranean basin, few data are available for North Africa. In this study, a total of 1489 sandflies were collected in 2008 in Tunisia from two sites, bioclimatically distinct, located 235 km apart, and identified morphologically. Sandfly species comprised Phlebotomus perniciosus (52.2%), Phlebotomus longicuspis (30.1%), Phlebotomus papatasi (12.0%), Phlebotomus perfiliewi (4.6%), Phlebotomus langeroni (0.4%) and Sergentomyia minuta (0.5%). PCR screening, using generic primers for the genus Phlebovirus, resulted in the detection of ten positive pools. Sequence analysis revealed that two pools contained viral RNA corresponding to a novel virus closely related to sandfly fever Naples virus. Virus isolation in Vero cells was achieved from one pool. Genetic and phylogenetic characterization based on sequences in the three genomic segments showed that it was a novel virus distinct from other recognized members of the species. This novel virus was provisionally named Punique virus. Viral sequences in the polymerase gene corresponding to another phlebovirus closely related to but distinct from sandfly fever Sicilian virus were obtained from the eight remaining positive pools.
Project description:BackgroundIn northern Tunisia, the co-circulation of two related sand fly-borne phleboviruses, Toscana virus (TOSV) and Punique virus (PUNV) was previously demonstrated. In contrast to TOSV, a prominent human pathogen, there is no data supporting that PUNV is capable to infect and cause disease to humans. We studied the respective involvement of TOSV and PUNV in human infections in northern Tunisia through a seroprevalence study.MethodsThe presence of TOSV and PUNV neutralising antibodies (NT-Ab) was tested in human sera collected from 5 districts of the governorate of Bizerte, and the titres of NT-Ab were estimated by microneutralisation (MN) assay.Principal findingsA total of 1,273 sera were processed. TOSV and PUNV NT-Ab were detected in 522 (41%) and 111 sera (8.72%) respectively. TOSV seroprevalence varied from 17.2% to 59.4% depending on the district. Analysis of TOSV geometric mean titre values demonstrated a constant increase according to the age. The vast majority of sera containing NT-Ab were found to be more reactive toward TOSV than PUNV. Indeed, past infections with PUNV and TOSV were undisputable for 5 and 414 sera, respectively.ConclusionsPUNV may be capable to infect humans but at a low rate. TOSV is responsible for the vast majority of human infections by sand fly-borne phleboviruses in northern Tunisia. TOSV must be considered by physician and tested in diagnostic laboratories for patients with meningitis and unexplained fever in northern Tunisia.
Project description:A new virus was isolated from three independent pools of Phlebotomus perniciosus sandflies (Diptera; Psychodidae) trapped in two regions of southeastern France, located 90 miles apart. Microscopic, antigenic and genetic analyses indicate that this novel virus belongs to the genus Phlebovirus in the family Bunyaviridae. The new virus is designated Massilia virus since the first isolate was obtained from sandflies collected in the suburban area of Marseille. The complete genome sequence was determined and used to compare the genetic and phylogenetic relationships of Massilia virus with other phleboviruses. Genetic and antigenic properties were employed to address whether or not Massilia virus should be considered a new species within the genus, or a member of a previously recognized species. Cerebrospinal fluid specimens, collected from local patients with central nervous system infections during the previous four-year period were tested for the presence of Massilia virus RNA, but gave negative results. In conclusion, Massilia virus is proposed as a member of the Sandfly fever Naples virus complex; its public health importance has yet to be determined.
Project description:Toscana virus (TOSV, Phlebovirus, family Bunyaviridae) infection is one of the most prevalent arboviruses in Spain. Within the objectives of a multidisciplinary network, a study on the epidemiology of TOSV was conducted in Granada, in southern Spain. The overall seroprevalence rate was 24.9%, significantly increasing with age. TOSV was detected in 3 of 103 sandfly pools by viral culture or reverse transcription-polymerase chain reaction from a region of the L gene. Nucleotide sequence homology was 99%-100% in TOSV from vectors and patients and 80%-81% compared to the Italian strain ISS Phl.3. Sequencing of the N gene of TOSV isolates from patients and vectors indicated 87%-88% and 100% homology at the nucleotide and amino acid levels, respectively, compared to the Italian strain. These findings demonstrate the circulation of at least 2 different lineages of TOSV in the Mediterranean basin, the Italian lineage and the Spanish lineage.
Project description:Toscana virus (TOSV) is an arthropod-borne phlebovirus belonging to the Sandfly fever Naples virus species (genus Phlebovirus, family Bunyaviridae). Here, we report the complete coding sequences of six TOSV strains isolated from human patients having acquired the infection in southeastern France during a 12-year period.
Project description:Distribution of Toscana virus (TOSV) is evolving with climate change, and pathogenicity may be higher in nonexposed populations outside areas of current prevalence (Mediterranean Basin). To characterize genetic diversity of TOSV, we determined the coding sequences of isolates from Spain and France. TOSV is more diverse than other well-studied phleboviruses (e.g.,Rift Valley fever virus).
Project description:Members of the family Rhabdoviridae have been assigned to eight genera but many remain unassigned. Rhabdoviruses have a remarkably diverse host range that includes terrestrial and marine animals, invertebrates and plants. Transmission of some rhabdoviruses often requires an arthropod vector, such as mosquitoes, midges, sandflies, ticks, aphids and leafhoppers, in which they replicate. Herein we characterize Niakha virus (NIAV), a previously uncharacterized rhabdovirus isolated from phebotomine sandflies in Senegal. Analysis of the 11,124 nt genome sequence indicates that it encodes the five common rhabdovirus proteins with alternative ORFs in the M, G and L genes. Phylogenetic analysis of the L protein indicate that NIAV's closest relative is Oak Vale rhabdovirus, although in this analysis NIAV is still so phylogenetically distinct that it might be classified as distinct from the eight currently recognized Rhabdoviridae genera. This observation highlights the vast, and yet not fully recognized diversity, of this family.