Seroprevalence of Toscana virus in blood donors in mainland Portugal

BACKGROUND

Toscana virus (TOSV; Phlebovirus toscanaense), a phlebovirus transmitted by sand flies, is a growing public health concern in the Mediterranean region, with infections often being asymptomatic but potentially leading to neuroinvasive disease. Despite its presence in neighboring countries, data on TOSV seroprevalence in Portugal are limited. This study aimed to estimate the national seroprevalence of TOSV among blood donors in mainland Portugal and explore associations with sociodemographic factors and Leishmania infection.

METHODS

A cross-sectional study was conducted using serum samples from 3593 blood donors across mainland Portugal, collected between February and June 2022. Anti-TOSV antibodies were detected via microneutralization assay, and anti-Leishmania antibodies had previously been tested using ELISA. Sociodemographic data were obtained from self-administered questionnaires. Seroprevalence was estimated by region, and multivariate logistic regression was used to identify factors associated with TOSV infection.

RESULTS

Overall, the estimated national true seroprevalence of TOSV was 2.6% (95% CI 2.1-3.1%). Regional seroprevalence varied significantly, with the highest values (up to 14.8%) in Alto Alentejo, Baixo Alentejo, Douro, Alto Tâmega e Barroso and Oeste regions. Multivariate analysis showed that age ≥ 50 years (aOR 1.70, 95% CI 1.04-2.77), residing in the Alentejo region (aOR 3.05, 95% CI 1.85-5.02) and positive/borderline Leishmania serology (aOR 2.31, 95% CI 1.29-4.15) were significantly associated with TOSV infection.

CONCLUSIONS

This study highlights new areas of TOSV circulation in Portugal, particularly in regions with higher Leishmania seroprevalence and visceral leishmaniasis incidence, suggesting co-circulation of these pathogens. Although a lower seroprevalence was obtained compared to neighboring countries, TOSV should still be considered in the differential diagnosis of viral meningitis and encephalitis in Portugal, especially in potentially high-risk regions. Further research is needed to better understand the ecological drivers of TOSV distribution in Portugal.

Toscana virus: A comprehensive review of 1381 cases showing an emerging threat in the Mediterranean regions

BACKGROUND

Toscana virus (TOSV) is a sand fly-borne phlebovirus causing central nervous system (CNS) infection in Mediterranean countries, during summer season. However, clinical aspects of the disease caused by this virus are poorly known by clinicians, so that its prevalence is probably underestimated due to a lack of diagnosis.

STUDY DESIGN

The data was gathered from all available case series and retrospective studies identifying TOSV as the causative viral agent. The informations of age, sex, clinical characteristics, laboratory findings, imaging results and clinical outcomes of TOSV infection were recorded and analyzed.

RESULTS

A total of 95 articles including TOSV infections resulting in a total of 1381 cases, were analyzed. Our findings indicate that TOSV affects individuals across various age groups, with a median age of 44.45 years. A notable disparity in infection rates between genders, with men being significantly more likely to present symptoms due to TOSV than women, with a sex ratio of 2.0. The clinical presentation of TOSV infection encompasses a range of symptoms, including fever, headache, retro-orbital pain, neurological and muscular manifestations with less common reports of cutaneous and gastrointestinal symptoms. To date, six fatalities have been attributed to TOSV infections, with a median age of 76 years. Diagnostic evaluation of TOSV infections often involves the analysis of cerebrospinal fluid, where findings may include an elevated white blood cell count.

CONCLUSIONS

These findings underscore the diverse clinical manifestations of TOSV infections including flu like symtomps. TOSV is an emerging infectious threat that warrants inclusion in the diagnostic protocols for patients presenting with CNS, particularly within the Mediterranean basin or for those with recent travel history to endemic regions during warmer months when sand flies are actively circulating.

Toscana virus - an emerging Mediterranean arbovirus transmitted by sand flies

Toscana virus (TOSV) is an emerging arthropod-borne virus (arbovirus) of medical importance that is increasing its range across much of the Mediterranean Basin, Europe and the Middle East. Transmitted by Phlebotomus spp. sand flies, it is the most clinically relevant sand fly-borne phlebovirus. Initially isolated in the Tuscany region of Central Italy, it has now been detected in multiple countries that surround this geographical area. Infection of the vertebrate host can cause fever and neurological disease, following the dissemination of the virus to the brain. The prevalence is high in some regions, with a notable percentage of individuals showing seroconversion. TOSV can be a leading cause of acute meningitis and encephalitis (AME) during the summer months. In this comprehensive review, we will focus on several key topics. We discuss how TOSV has spread to establish outbreaks of infection in both humans and animals around the Mediterranean and the wider region. Clinical aspects of TOSV infection in humans are described, along with the best standards in diagnosis. Finally, we focus our discussion on the role of the sand fly vector, describing their biology, vector competency, implications for putative vertebrate reservoirs, the effect of the climate emergency on sand fly distribution and the putative role that sand fly-derived salivary factors may have on modulating host susceptibility to TOSV infection.

Toscana Virus in Wild-Caught Sand Flies in Portugal, Findings from the National Vector Surveillance Network, 2023

Phlebotomine sand flies play a crucial role in both human and veterinary medicine, acting as vectors for Leishmania parasites and most known phleboviruses. In Portugal, the REVIVE program, a comprehensive national surveillance network under the Ministry of Health, has included sand fly surveys since 2016. REVIVE aims to identify existing sand fly species in the country, determine which pathogens are circulating among them, and provide actionable insights for prevention and control measures when necessary. In this way, annually, from May to October, health technicians collect sand flies across mainland Portugal with CDC light traps. The collected sand flies are sent to the Centre for Vectors and Infectious Diseases Research for species identification and molecular screening of pathogens. On 21 September 2023, Toscana virus (TOSV), a well-known phlebovirus in the Mediterranean region due to its capacity to cause neurological disease, was detected in a pool of 30 sand flies collected in Algarve, the southernmost region of Portugal. A 668 bp partial sequence of the nucleoprotein gene shows similarity with TOSV strains from Spain. To our knowledge, this is the first detection of TOSV in its vector in this country, having previously only been reported in vertebrate hosts. These findings highlight the important role of ongoing surveillance efforts in monitoring and understanding the dynamics of sand fly-borne diseases in Portugal.

Sandfly-Borne Phleboviruses in Portugal: Four and Still Counting

According to ICTV, there are currently 66 known phlebovirus species. More than 40 of these viruses were isolated or detected in phlebotomine sandflies and some of them are known pathogens. In Portugal, information about sandfly-borne phleboviruses is scarce and scattered sandfly-borne diseases are neglected and often not considered in differential diagnoses. The main objective of this work was to gather the existing information and to raise awareness about the circulating phleboviruses in this country. To date, Massilia and Alcube phleboviruses have been isolated from sandflies in southern Portugal. Human infections with Toscana and Sicilian phleboviruses have been reported, as well as seroprevalence in cats and dogs. More studies are needed in order to understand if the viruses isolated during the entomological surveys have an impact on human health and to fully understand the real importance of the already recognized pathogens in our country.

Human seroprevalence of Toscana virus and Sicilian phlebovirus in the southwest of Portugal

Toscana virus (TOSV) is emergent in the Mediterranean region and responsible for outbreaks of encephalitis or meningoencephalitis. Sicilian phlebovirus (SFSV) cause epidemics of febrile illness during the summer. The aim of this study was to evaluate the presence of antibodies against TOSV and SFSV in humans in the southwest of Portugal. Neutralizing antibodies to TOSV and SFSV were respectively detected in 5.3% and 4.3% out of 400 human sera tested highlighting the need to increase public health awareness regarding phleboviruses and to include them in the differential diagnosis in patients presenting with fever of short duration and neurological manifestations.

Epidemiology of Toscana virus in South Tuscany over the years 2011-2019

BACKGROUND

Toscana virus (TOSV) is a Phlebovirus transmitted to humans by phlebotomines and represent an etiological agent of acute aseptic meningitis (AAM) in countries where the virus is endemic, including Italy. Incidence of TOSV infections is closely associated with the geographical distribution of the phlebotomine vectors which in turn is affected by climate changes that determine survival and spread. As a result, TOSV infections show a seasonal trend with a peak of incidence in summer months.

OBJECTIVES

To measure the prevalence of TOSV infections in AAM patients in central Italy and evaluate the climate changes in phlebotomine vectors ecology and virus propagation.

STUDY DESIGN

One thousand and seventy-three cerebrospinal fluid samples (CSFs), collected from patients with suspected viral meningitis, were collected over nine years (2011-2019) during the May to October period and tested for viruses most commonly associated with AAM. Serum samples addressed to the Microbiology and Virology Unit of "S. Maria delle Scotte" Hospital for confirmation acute TOSV infection (n = 324) were tested for TOSV-specific IgM and IgG.

RESULTS

Among the CSF samples, 1.3% were positive for Enteroviruses; 0.9% for Varicella zoster virus, 1.9% for Herpes simplex virus type-1/2 and 4.6% for TOSV. Serum IgM analyses disclosed TOSV-specific IgM in 27.1% of sera suggesting the predominant involvement of TOSV in neuroinvasive infections.

CONCLUSIONS

This data confirms the predominant role of TOSV as causative agent of AAM during the summer time in endemic countries. Moreover, climate changes affecting phlebotomine vectors persistence, reproduction and activity could be involved in the cyclic nature of TOSV infection reported during the last nine years.

Phlebovirus seroprevalence in Austrian Army personnel returning from missions abroad

Background

Phleboviruses are mainly transmitted by sand flies and infections can result in various symptoms, including meningitis and meningoencephalitis. In endemic regions, seroprevalences in humans and animals are high. Military personnel on missions in endemic areas are at increased risk of infection, however, for soldiers from central European countries, data are scarce. The aims of this study were to determine the exposure to phleboviruses of Austrian soldiers returning from missions abroad and to assess potential risk factors. A retrospective serological study was performed with sera of 753 healthy Austrian soldiers returning from missions in Bosnia and Herzegovina (BIH, n = 61), Kosovo (n = 261), Syria (n = 101) and Lebanon (n = 63) and of soldiers prior to their missions (n = 267).

Results

Altogether, 119 sera (15.8%, 119/753) were positive for anti-Phlebovirus IgG antibodies, with highest seroprevalences found in soldiers returning from Kosovo (20.69%, 54/261), followed by Syria (17.82%, 18/101), Lebanon (14.29%, 9/63) and BIH (11.48%, 7/61). Of the soldiers tested prior to their missions 11.61% (31/267) were positive. Of the 119 seropositive individuals, 30 (25.2%, 30/119) also had anti-Phlebovirus IgM antibodies. Phlebovirus seropositivity significantly correlated with symptoms of febrile illness during the respective mission (OR: 1.9, 95% CI: 1.1–3.4, P = 0.03) and with Leishmania seropositivity (OR: 2.7, 95% CI: 1.2–5.8, P = 0.009). Also, the outdoor activity “running” during the mission showed a strong trend towards an association with Phlebovirus seropositivity (OR: 1.9, 95% CI: 0.9–4.4, P = 0.08), and seropositivity generally increased with the duration of a mission (OR: 2.5, 95% CI: 0.9–7.5, P = 0.07).

Conclusions

This study indicates that soldiers are exposed to sand flies and at significant risk for Phlebovirus infection during missions in the Mediterranean area and the Middle East. Adequate prevention measures should be applied particularly during vespertine outdoor activities.

Neglected vector-borne bacterial diseases and arboviruses in the Mediterranean area

Arthropod vectors can transmit pathogenic microorganisms from one vertebrate to another during their blood meal. Although some vector-borne diseases have been eradicated in the Mediterranean area, such as malaria and dengue, recent endemic microorganisms (Toscana virus, Rickettsia spp.) remain neglected even though they cause many more cases. New diagnostic tools and innovative tools for the identification and characterization of vector species and microorganisms have been developed at IHU Méditerranée Infection, either internally or through collaborative and integrated projects. We have detected Rickettsia slovaca as a human pathogen and have described the disease; we have shown that Rickettsia felis can be transmitted by Anopheles mosquitoes; we have emphasized the increasing importance of bedbug (Cimex lectularius) as a potential vector of Bartonella quintana; and we have described the Toscana virus, a major agent of meningitis and meningoencephalitis which was disseminated in North Africa and Central and Eastern Europe, where it frequently cocirculates with a large number of newly described phleboviruses transmitted by sand flies.

Phlebotomine sand fly-borne pathogens in the Mediterranean Basin: Human leishmaniasis and phlebovirus infections

Pathogens transmitted to humans by phlebotomine sand flies are neglected, as they cause infectious diseases that are not on the priority list of national and international public health systems. However, the infections caused by protozoa of the Leishmania genus and viruses belonging to the Phlebovirus genus (family Phenuiviridae)—the most significant group of viruses transmitted by sand flies—have a relevant role for human pathology. These infections are emerging in the Mediterranean region and will likely spread in forthcoming decades, posing a complex threat to human health. Four species and 2 hybrid strains of Leishmania are pathogenic for humans in the Mediterranean Basin, with an estimated annual incidence of 239,500–393,600 cases of cutaneous leishmaniasis and 1,200–2,000 cases of visceral leishmaniasis. Among the phleboviruses, Toscana virus can cause neuroinvasive infections, while other phleboviruses are responsible for a typical “3-day fever”; the actual incidence of Phlebovirus infections in the Mediterranean area is unknown, although at least 250 million people are exposed. Here, we reviewed the current literature on epidemiology of sand fly–borne infections in the Mediterranean Basin, with a focus on humans. Our analysis indicates the need for increased public health activities directed to determine the disease burden of these infections as well as to improve their surveillance. Among the emerging challenges concerning sand fly–borne pathogens, the relationships between sand fly–borne protozoa and viruses should be considered in future studies, including epidemiological links between Leishmania and phleboviruses as well as the conditional capacity for these pathogens to be involved in interactions that may evolve towards increased virulence.

Of phlebotomines (sandflies) and viruses: a comprehensive perspective on a complex situation

Old World sandfly-borne phleboviruses are classified into three serological complexes: Sandfly fever Sicilian, Sandfly fever Naples and Salehabad. Human pathogens (febrile illness ['sandfly fever'], neuroinvasive infections) belong to the two first complexes. The increasing number of newly discovered sandfly-borne phleboviruses raises concerns about their medical and veterinary importance. They occupy a wide geographic area from Mediterranean basin to North Africa and the Middle East to the central Asia. At least nine species of sandflies can transmit these viruses. Recent results suggest that sandfly vectors are not as specific for viruses as initially believed. Recent seroprevalence studies demonstrate that humans and domestic animals are heavily exposed. Specific molecular diagnostic methods must be developed and implemented in clinical microbiology laboratories.

Practical Guidelines for Studies on Sandfly-Borne Phleboviruses: Part I: Important Points to Consider Ante Field Work

The purpose of this review is to provide practical information to help researchers intending to perform "from field to laboratory" studies on phleboviruses transmitted by sandflies. This guideline addresses the different steps to be considered starting from the field collection of sandflies to the laboratory techniques aiming at the detection, isolation, and characterization of sandfly-borne phleboviruses. In this guideline article, we address the impact of various types of data for an optimal organization of the field work intending to collect wildlife sandflies for subsequent virology studies. Analysis of different data sets should result in the geographic positioning of the trapping stations. The overall planning, the equipment and tools needed, the manpower to be deployed, and the logistics to be anticipated and set up should be organized according to the objectives of the field study for optimal efficiency.

Serological association between Leishmania infantum and sand fly fever Sicilian (but not Toscana) virus in sheltered dogs from southern Portugal

Background

Phlebotomine sand fly-borne diseases such as leishmanioses and phleboviruses are emerging threats to animal and public health. Canine leishmaniosis caused by Leishmania infantum is an endemic zoonosis in Portugal. Antibodies to Toscana virus (TOSV) and sand fly fever Sicilian virus (SFSV) were also reported in dogs from the south of the country. The aim of this work was to evaluate a possible association between exposure to L. infantum, TOSV and SFSV in sheltered dogs from the south of Portugal.

Results

Seventy-six (13.1%) out of 581 dogs were seropositive for L. infantum, 327 (56.3%) for SFSV and 36 (6.2%) for TOSV. Six dogs were co-exposed with L. infantum and TOSV, 51 with L. infantum and SFSV and 25 with TOSV and SFSV. One dog had antibodies to the three pathogens. Leishmania infantum seroprevalence was significantly higher in pure breed dogs than in mongrels and in dogs with clinical signs while SFSV positivity was significantly higher in males, in pure and cross-breed dogs than in mongrels and in those not treated with insecticides. Seroprevalence for both viruses was significantly higher in dogs over than 7 years-old than in those aged 1–7. A significant association was observed between the presence of antibodies to L. infantum and SFSV.

Conclusions

The presence of antibodies to several phlebotomine sand fly-borne pathogens in dogs, reinforces the need to implement efficient prophylactic measures to prevent infection among vertebrate hosts including humans. The results also indicate that dogs are good sentinels for assessing human exposure to TOSV and SFSV. Further studies must be performed to elucidate the role of dogs in the dynamics of transmission and if they can play a role as amplifying or reservoir hosts in the natural cycle of these viruses. Public and animal health impacts of these phleboviruses in Portugal should be addressed via serological and virological studies on both phlebotomine sand flies and vertebrate hosts, especially on humans.

Neutralization-based seroprevalence of Toscana virus and sandfly fever Sicilian virus in dogs and cats from Portugal

Sandfly-borne phleboviruses are endemic in the Mediterranean basin. However, levels of exposure of human and animal populations are inadequately researched. Toscana virus (TOSV) is present in Portugal where it causes human infection and disease; in contrast there are few data for sandfly fever Sicilian virus (SFSV) which has neither been isolated nor detected by molecular tests and for which there are only limited serological data. The sera collected from 1160 dogs and 189 cats in southern Portugal were tested for the presence of neutralizing antibodies against TOSV and SFSV, two viruses recognized as distinct serocomplexes in the Mediterranean region. Our data showed (i) seropositivity to TOSV and SFSV in dogs at a rate of 6.8 and 50.8 %, respectively, and (ii) that 3.7 % of cats were seropositive for TOSV. TOSV findings are in line with previous results obtained with less stringent serological assays. Our results for SFSV in dogs clearly indicate that the virus is circulating widely and that humans may be exposed to infection via the dogs. Although the presence of SFSV was suggested by haemagglutination inhibition in 4/1690 human sera in 1974, this is the first time, as far as we know, that SFSV has been shown to circulate so widely in dogs in Portugal. Future studies should be directed at isolating strains of SFSV in Portugal from dogs, humans and sandflies collected in high prevalence regions. As dogs appear to be good sentinels for SFSV, their role as a possible reservoir in the natural cycle should also be considered.

Genetic characterization of Arrabida virus, a novel phlebovirus isolated in South Portugal

In order to detect phleboviruses' natural infection in sandflies, an entomological survey was carried out, from May to October in 2007 and 2008, in Arrábida region in the south of Portugal. The isolation of a new phlebovirus was achieved after inoculation of a sandfly pool homogenate in Vero E6 cells. Based on the phylogenetic analysis of the complete genome sequences from the Small, Medium and Large, segments obtained with Next Generation sequencing, we can assume that the new phlebovirus, provisionally named Arrabida virus, is closely related to Massilia, Granada and Punique viruses. This is the first isolation of a sandfly-borne phlebovirus from the Sandfly Naples Fever Virus group in Portugal. Further investigation is needed in order to assess the importance of this phlebovirus for Public Health.

Sampling strategies for phlebotomine sand flies (Diptera: Psychodidae) in Europe

The distribution of phlebotomine sand flies is widely reported to be changing in Europe. This can be attributed to either the discovery of sand flies in areas where they were previously overlooked (generally following an outbreak of leishmaniasis or other sand fly-related disease) or to true expansion of their range as a result of climatic or environmental changes. Routine surveillance for phlebotomines in Europe is localized, and often one of the challenges for entomologists working in non-leishmaniasis endemic countries is the lack of knowledge on how to conduct, plan and execute sampling for phlebotomines, or how to adapt on-going sampling strategies for other haematophagous diptera. This review brings together published and unpublished expert knowledge on sampling strategies for European phlebotomines of public health concern in order to provide practical advice on: how to conduct surveys; the collection and interpretation of field data; suitable techniques for the preservation of specimens obtained by different sampling methods; molecular techniques used for species identification; and the pathogens associated with sand flies and their detection methods.

Toscana virus infections: a case series from France

Toscana virus (TOSV) is a neglected sandfly-borne pathogen in Mediterranean countries. Although discovered four decades ago, articles that describe the clinical aspects are scarce and consist mostly of case reports, with few series of cases. We studied retrospectively symptomatic TOSV infections in patients hospitalized in Marseille (France) from 2004 to 2011. Seventeen patients were classified as probable or confirmed cases. Fourteen cases (82%) occurred between June and September, and 3 cases in March, April and November. Two cases were potentially imported from Croatia and Tuscany. All patients presented with fever and neurological signs were observed such as aseptic meningitis (n = 6), muscular symptoms (n = 3), or encephalitis (n = 4). The outcome was always favorable. At the acute stage, anti TOSV IgM were observed in 14/17 patients, neutralization tests were positive for 3/8 patients, and RT-PCR confirmed TOSV infections in 5/8 CSF specimens.

Phlebotomine sandflies and the spreading of leishmaniases and other diseases of public health concern

Phlebotomine sandflies transmit pathogens that affect humans and animals worldwide. We review the roles of phlebotomines in the spreading of leishmaniases, sandfly fever, summer meningitis, vesicular stomatitis, Chandipura virus encephalitis and Carrión's disease. Among over 800 species of sandfly recorded, 98 are proven or suspected vectors of human leishmaniases; these include 42 Phlebotomus species in the Old World and 56 Lutzomyia species in the New World (all: Diptera: Psychodidae). Based on incrimination criteria, we provide an updated list of proven or suspected vector species by endemic country where data are available. Increases in sandfly diffusion and density resulting from increases in breeding sites and blood sources, and the interruption of vector control activities contribute to the spreading of leishmaniasis in the settings of human migration, deforestation, urbanization and conflict. In addition, climatic changes can be expected to affect the density and dispersion of sandflies. Phlebovirus infections and diseases are present in large areas of the Old World, especially in the Mediterranean subregion, in which virus diversity has proven to be higher than initially suspected. Vesiculovirus diseases are important to livestock and humans in the southeastern U.S.A. and Latin America, and represent emerging human threats in parts of India. Carrión's disease, formerly restricted to regions of elevated altitude in Peru, Ecuador and Colombia, has shown recent expansion to non-endemic areas of the Amazon basin.

Emergence of Toscana virus in the mediterranean area

Toscana virus (TOSV) is an arthropod-borne virus, identified in 1971, from Phlebotomus perniciosus and Phlebotomus perfiliewi in central Italy. TOSV belongs to the Phlebovirus genus within the Bunyaviridae family. As other bunyaviruses, the genome of TOSV consists of 3 segments (S for small, M for Medium, and L for Large) respectively encoding non structural and capsid proteins, envelope structural proteins, and the viral RNA-dependant RNA-polymerase. It is transmitted by sand flies. Therefore its distribution is dictated by that of the arthropod vectors, and virus circulation peaks during summertime when sandfly populations are active. Here, we reviewed the epidemiology of TOSV in the old world. First evidence of its pathogenicity for humans, specifically its propensity to cause central nervous system (CNS) infections such as meningitis and encephalitis, was reported in central Italy. After 2000, it was recognized that TOSV had a much larger geographic distribution than initially believed, and was present in most of the Western European countries located on the northern border of the Mediterranean Sea (Portugal, Spain, France, Greece, Croatia) as well as eastern countries such as Cyprus and Turkey. In the countries where TOSV is present, it is among the three most prevalent viruses in meningitis during the warm seasons, together with enteroviruses and herpesviruses. Up to now, epidemiological data concerning Northern Africa and other countries located south of the Mediterranean are scarce. TOSV must be considered an emerging pathogen. Despite the important role played by TOSV in CNS infections, it remains a neglected agent and is rarely considered by physicians in diagnostic algorithms of CNS infections and febrile illness during the warm season, probably because of the lack of information.

Seroprevalence of and risk factors for Toscana and Sicilian virus infection in a sample population of Sicily (Italy)

OBJECTIVE

The present study aimed to assess seroprevalence of and risk factors for Toscana (TOSV) and Sicilian (SFSV) virus infections in a sample of Sicilian subjects.

METHODS

A cross-sectional seroepidemiological study was conducted on 271 individuals. Each participant completed a self-administrated questionnaire and provided a serum sample which was analyzed for the presence of IgG specific anti-TOSV and anti-SFSV viruses.

RESULTS

Overall, 90 subjects (33.2%) were positive for TOSV IgG, 25 (9.2%) were positive for SFSV IgG and 11 (4%) were positive for both the viruses. A higher risk for TOSV seropositivity was found in participants who were older (adjOR = 1.02 per year; 95% CI = 1.01-1.03), having a pet living outdoors (adjOR = 2.62; 95% CI = 1.42-4.83) and being obese (adjOR = 2.37; 95% CI = 1.06-5.30).

CONCLUSIONS

TOSV seroprevalence appears to be relatively high in Sicilian general population, especially in older adults, representing a potential public health concern. The observations that seropositivity for TOSV was not significantly associated with SFSV seropositivity, and none of the risk factors associated with TOSV were associated with SFSV seem to suggest that these two phleboviruses may have different ecology and transmission pathways.

Serological evidence of Toscana virus infection in Portuguese patients

Toscana virus (TOSV) is an emerging Phlebovirus of growing interest as a human pathogen in the Mediterranean Basin. In Portugal, however, little is known about the prevalence of TOSV infection. The aim of this work was to perform a seroprevalence study in patients with requests for laboratory diagnosis of vector-borne viruses. A total of 538 patients with and without neurological signs from 2004 to 2008 were studied by in-house indirect immunofluorescence assay and commercial enzyme-linked immunosorbent assays. A prevalence of 4.2% for IgG antibodies was found in the group of patients with neurological signs. Five (3%) of these had recent infections. In the group with no neurological signs, the IgG prevalence was 1.3%. Two samples, belonging to two patients, were also confirmed with plaque reduction neutralization tests with the TOSV ISS. Phl.3 Italian strain. This work showed that TOSV is present and causing disease from north to south in Portugal. The probable circulation of different phlebovirus serotypes in Portugal emphasizes the need for further studies.

Toscana virus epidemiology: from Italy to beyond

Toscana virus (TOSV) is an arthropod-borne virus which is transmitted to humans by Phlebotomus spp sandflies. Infection is the cause of brain injuries, such as aseptic meningitis and meningoencephalitis, in Italy mainly during the summer. More recently some unusual clinical manifestations due to TOSV with severe sequelae, such as ischemic complications and hydrocephalus, have been reported. TOSV represents an important emerging pathogen and its presence is being investigated in several European countries on the Mediterranean basin, including Italy, France, Spain, Portugal and Cyprus. Phylogenetic analysis has distinguished two genotypes of TOSV, A and B; the first is circulating mainly in Italy and the second in Spain, indicating a different geographic distribution possibly related to the vector. This distribution, evolving with the climate, globalization and habitat modification, has implications for the epidemiology of TOSV.

Toscana virus epidemiology: from Italy to beyond

Toscana virus (TOSV) is an arthropod-borne virus which is transmitted to humans by Phlebotomus spp sandflies. Infection is the cause of brain injuries, such as aseptic meningitis and meningoencephalitis, in Italy mainly during the summer. More recently some unusual clinical manifestations due to TOSV with severe sequelae, such as ischemic complications and hydrocephalus, have been reported. TOSV represents an important emerging pathogen and its presence is being investigated in several European countries on the Mediterranean basin, including Italy, France, Spain, Portugal and Cyprus. Phylogenetic analysis has distinguished two genotypes of TOSV, A and B; the first is circulating mainly in Italy and the second in Spain, indicating a different geographic distribution possibly related to the vector. This distribution, evolving with the climate, globalization and habitat modification, has implications for the epidemiology of TOSV.

Molecular and serological evidence for the presence of novel phleboviruses in sandflies from northern algeria

During summer 2007, a total of 785 phlebotomine flies were trapped in northern Algeria, identified morphologically, organised as monospecific pools and tested for the presence of phlebovirus RNA using degenerate primers. Three pools were positive, and the corresponding PCR products were cloned and sequenced. Viral sequences corresponding to two phleboviruses distinct from each other were detected in sandflies circulating in two close locations (140 km apart) in Northern Algeria. The 3 sequences were aligned with homologous polymerase sequences retrieved from the Genbank database, in order to examine their phylogenetic relationships. One viral sequence (from Phlebotomus papatasi) was closely related to but distinct from a sequence obtained from Phlebotomus ariasi sandflies trapped in Algeria in 2006. The two other viral sequences (from Phlebotomus longicuspis) were genetically distantly related to sequences corresponding to virus members of the Sandfly fever Naples virus species and although falling within the same group, this clearly represents a second distinct novel lineage. These results are indicative of a high genetic heterogeneity within sandflies trapped in a relatively small geographic area. Seroprevalence studies conducted on sera from populations living in the same areas indicated that humans can be infected by these viruses.

Molecular and serological evidence for the presence of novel phleboviruses in sandflies from northern algeria

During summer 2007, a total of 785 phlebotomine flies were trapped in northern Algeria, identified morphologically, organised as monospecific pools and tested for the presence of phlebovirus RNA using degenerate primers. Three pools were positive, and the corresponding PCR products were cloned and sequenced. Viral sequences corresponding to two phleboviruses distinct from each other were detected in sandflies circulating in two close locations (140 km apart) in Northern Algeria. The 3 sequences were aligned with homologous polymerase sequences retrieved from the Genbank database, in order to examine their phylogenetic relationships. One viral sequence (from Phlebotomus papatasi) was closely related to but distinct from a sequence obtained from Phlebotomus ariasi sandflies trapped in Algeria in 2006. The two other viral sequences (from Phlebotomus longicuspis) were genetically distantly related to sequences corresponding to virus members of the Sandfly fever Naples virus species and although falling within the same group, this clearly represents a second distinct novel lineage. These results are indicative of a high genetic heterogeneity within sandflies trapped in a relatively small geographic area. Seroprevalence studies conducted on sera from populations living in the same areas indicated that humans can be infected by these viruses.

[Role of Toscana virus in meningo-encephalitis in Tunisia]

OBJECTIVES

To detect the presence of Toscana virus (TOSV) circulation in Tunisia and to study its role in viral meningo-encephalitis.

PATIENTS AND METHODS

A total of 315 (167 sera and 178 cerobrospinal fluid [CSF]) samples was investigated. These samples are colleted from Tunisian patients with neurological diseases during the period between January 2003 and December 2009. All samples were tested negative for enterovirus, Herpes Simplex virus and West Nile virus. Detection for IgM and IgG specific to TOSV was done by ELISA tests.

RESULTS

Specific IgM for TOSV were detected in 10 % of patients with neurological diseases (31 cases). These recent infections were distributed throughout the study period and predominated during summer and automn. Patients were originated, in the majority from the coastal region. IgG were isolated in 22 cases (7 %) corresponding to previous infection.

CONCLUSION

This is the first report of TOSV circulating in Tunisia and its frequent implication in neurological diseases. These results incited to include TOSV as one of the viral etiologies to target in the diagnosis of viral meningitis and encephalitis in the country.

Punique virus, a novel phlebovirus, related to sandfly fever Naples virus, isolated from sandflies collected in Tunisia

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.