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

  • Martina Moriconi,

    Affiliation Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy

  • Gianluca Rugna,

    Affiliation Modena Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy

  • Mattia Calzolari,

    Affiliation Laboratory of Entomology, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Reggio Emilia, Italy

  • Romeo Bellini,

    Affiliation Department of Medical and Veterinary Entomology, Centro Agricoltura Ambiente “G. Nicoli,” Crevalcore, Italy

  • Alessandro Albieri,

    Affiliation Department of Medical and Veterinary Entomology, Centro Agricoltura Ambiente “G. Nicoli,” Crevalcore, Italy

  • Paola Angelini,

    Affiliation Public Health Authority, Emilia-Romagna Region, Bologna, Italy

  • Roberto Cagarelli,

    Affiliation Public Health Authority, Emilia-Romagna Region, Bologna, Italy

  • Maria P. Landini,

    Affiliations Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy, Istituto di Ricovero e Cura a carattere scientifico, Istituto Ortopedico Rizzoli, Bologna, Italy

  • Remi N. Charrel ,

    Contributed equally to this work with: Remi N. Charrel, Stefania Varani

    Affiliations UMR “Emergence des Pathologies Virales” (EPV: Aix-Marseille Univ-IRD 190-Inserm 1207-EHESP), Marseille, France, Fondation IHU Mediterranee Infection, APHM Public Hospitals of Marseille, Marseille, France

  • Stefania Varani

    Contributed equally to this work with: Remi N. Charrel, Stefania Varani

    stefania.varani@unibo.it

    Affiliations Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy, Unit of Clinical Microbiology, Regional Reference Centre for Microbiological Emergencies (CRREM), St. Orsola-Malpighi University Hospital, Bologna, Italy

Abstract

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.

Introduction

Pathogens transmitted to humans and animals by phlebotomine sand flies are relatively neglected, as they cause infectious diseases that are not on the priority list of national and international public health agencies in Europe. However, these diseases are emerging in southern Europe [1]. Among sand fly–borne pathogens, protozoa of the Leishmania genus and viruses belonging to the Phlebovirus genus (order Bunyavirales, family Phenuiviridae)—the most significant group of viruses transmitted by sand flies—contribute significantly to human pathologic disease. Four recognized species and 2 hybrid strains of Leishmania are known to be pathogenic for humans in the Mediterranean region, with an estimated annual incidence of 239,500–393,600 cases of cutaneous leishmaniasis (CL) and 1,200–2,000 cases of visceral leishmaniasis (VL) [2]. Among the phleboviruses, Toscana virus (TOSV) can cause neuroinvasive infections, while other phleboviruses are responsible for a typical “3-day fever” or “pappataci fever;” the actual incidence of Phlebovirus infections in the Mediterranean area is unknown. However, at least 250 million people are potentially exposed [3]. The aim of this study is to provide an overview of the epidemiology of sand fly–borne infections in the Mediterranean Basin, with particular focus on humans.

Methods

A comprehensive literature search was conducted on the distribution of Leishmania and Phlebovirus species responsible for human infection in the Mediterranean region. An additional search was dedicated to identifying the reservoir(s) of Leishmania and Phlebovirus. We analyzed all articles listed in the PubMed database in English, French, Italian, and Spanish between 1980 and December 2016, when the final search was conducted. The search terms used included leishmanial species, phlebovirus species, reservoir species, and countries included in the study. Titles relevant to the scope of this review were obtained in full text and selected for inclusion. Unpublished data were not considered. Data on the presence of Leishmania and/or Phlebovirus detection were reported on a geographic information system (GIS) at country level. Maps were created in the open source GIS software, QGIS 2.12 (www.qgis.org).

Characteristics of phlebotomine sand fly–borne pathogens (Leishmania and Phlebovirus)

Leishmania

The genus Leishmania is composed of protozoa belonging to the Trypanosamatidae family, order Kinetoplastida. Within the genus, there are 2 subgenera of medical importance that were created on the basis of the parasite developmental patterns within the sand fly gut: Leishmania (all development anterior to the pylorus) and Viannia (developing in the hindgut and pylorus) [4]. On the basis of multilocus enzyme electrophoresis (MLEE), from which the current Leishmania taxonomy originates, leishmanial species are grouped within each subgenus into so-called “species complexes” or “complexes,” which are distributed in countries with a subtropical climate [5].

These protozoa have a digenetic life cycle, requiring a susceptible vertebrate host and a permissive insect vector, which allow their transmission [4]. The blood-feeding females of phlebotomine sand flies are considered the only natural vectors of leishmanial species. The genus Phlebotomus includes species responsible for the transmission of Leishmania in the Old World, while Lutzomyia species are responsible for the transmission of the parasite in the New World [4].

The morphological forms of these protozoa are: (1) an extracellular flagellated promastigote that may be found in sand fly gut and (2) an obligate intracellular nonflagellated amastigote, typically residing in monocyte macrophages of the mammalian host [4].

About 20 Leishmania species are known to be pathogenic for humans [6] and are differently distributed in the New and Old Worlds [5]. The species circulating in the Mediterranean region include L. donovani and L. infantum, causing VL, and L. tropica and L. major, which, together with dermotropic L. infantum strains and L. infantum/L. donovani hybrid, cause CL [4, 79]. A classification of human pathogenic Leishmania species circulating in the Mediterranean region is presented in Table 1.

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Table 1. Leishmanial species circulating in the Mediterranean region and pathogenic for humans.

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Survival of the Leishmania parasites depends on successful zoonotic or anthroponotic transmission and on suitable environment and climate. Although the areas in which different leishmanial species are diffused appear well defined, the risk for introduction of exotic species through travel or migration should be considered. The probability that new species could enter into a local transmission cycle depends on various factors, including the competence of sand flies for different leishmanial species; the presence of a suitable reservoir; and the contact between sand flies, reservoirs, and humans [1]. Considering these aspects, the introduction of zoonotic L. major to Europe is regarded as unlikely, as the fat sand rats and the gerbils—the natural animal reservoirs of L. major—live in the desert or semidesert areas of the African and Asian continents not found on the European continent [13]. On the contrary, the risk of introduction of anthroponotic L. tropica and L. donovani to Europe is not negligible because of the diffusion in various European countries of the respective vectors, P. sergenti and P. tobbi [14, 15].

CL cases caused by L. tropica were recorded in Greece for the first time in 1984 [16]. However, Garifallou et al. reported on the first biochemical typing of CL agents, while CL cases had been documented in Greece long before the 80s [17]. Strain typing indicated that the Greek strain of L. tropica closely resembled L. tropica strains from the Middle East and Asia [16].

The report of autochthonous cases of CL and VL caused by L. donovani (MON-37 zymodeme) in Cyprus [18] confirms the dynamic nature of this parasitic infection. MLEE analysis showed that the Cypriotic L. donovani MON-37 is closely related to 2 different strains belonging to L. donovani MON-309 zymodeme (Çukurova strains) and to L. donovani MON-308 zymodeme, both identified in Turkey and transmitted by P. tobbi [8]. Strains of L. donovani belonging to the MON-37 zymodeme are geographically the most widespread and give the impression of constituting a homogeneous group. However, multilocus microsatellite typing (MLMT) analysis revealed that MON-37 strains from Cyprus are clearly different compared with MON-37 strains from the Indian subcontinent, the Middle East, China, and East Africa [19]. A distinct MLMT study placed the Turkish strains and the Cypriotic strain in a subclade of a newly discovered group (Turkey/Cyprus non-MON-1 zymodeme group) within the L. donovani complex [8], suggesting the diffusion of these strains over neighboring areas in the European continent.

The reproduction mode (clonality versus sexuality) of the Leishmania parasite is still under debate, but the existence of natural hybrid strains suggests that the exchange of genetic material does occur. Recently, whole genome sequencing demonstrated that the çukurova strain is the progeny of a single outcrossing event between 1 parent related to L. infantum and an as-yet-unidentified parent belonging to the L. donovani complex [9]. Moreover, 2 hybrid strains produced by L. infantum and L. major were isolated in Portugal from immunocompromised patients suffering from VL, indicating that close phylogenetic association is not a necessary prerequisite for genetic exchange [20]. In addition, molecular techniques show that these chimeric strains contain the complete genome of both L. infantum and L. major. Genetic exchange may have potential implications such as emergence of virulent strains or increasing fitness [21, 22]. Indeed, L. infantum/L. major hybrid is capable of replicating in P. papatasi [22], while L. infantum/L. donovani hybrid replicates in P. tobbi and P. perniciosus [15], suggesting that hybrid strains may circulate in infected sand flies.

Phlebovirus

The genus Phlebovirus belongs to the family Phenuiviridae, order Bunyavirales [3]. Phleboviruses are enveloped, spherical viruses. The genome is a negative-sense, single-stranded RNA. The 3 RNA segments designated as large (L), medium (M), and small (S) encode the RNA-dependent RNA polymerase, the envelope glycoproteins, and the nucleoprotein, respectively. The single-stranded RNA segments have high mutation rates due to the lack of proofreading activity of the viral polymerase, which may result in genetic drift following point mutation, while the 3 genome segments are involved in reassortment/recombination, leading to the generation of new viruses [3].

The genus Phlebovirus includes 9 species; 70 antigenically distinct viruses are segregated into the 9 species, while 33 viruses are not yet attributed to one of these species [23].

In the Mediterranean area, phleboviruses transmitted by sand flies belong to 1 of the following groups: (i) 2 International Committee on Taxonomy of Viruses (ICTV)-recognized species, Sandfly fever Naples (SFNV) and Salehabad, (ii) 2 tentative species (Sandfly fever Sicilian virus [SFSV] and Corfou virus) [23]. Furthermore, Karimabad virus was erroneously listed in the Sandfly fever Naples species as demonstrated by Palacios et al. [24] and should be listed as a tentative species. A large number of new sand fly–borne phleboviruses were recently described, all of them belong to species/groups listed as (i) or (ii) (Table 2). A phlebovirus phylogeny reconstruction is depicted in Fig 1.

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Table 2. Pathogenic (or potentially pathogenic) phleboviruses for humans in the Mediterranean region.

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Fig 1. Phleboviruses phylogeny reconstruction.

Phylogenetic relationships between selected Old World sand fly–borne phleboviruses based on partial large (L) RNA sequences; phylogenetic relationships of selected amino acid sequences were inferred by using the maximum likelihood method based on the Jones-Taylor-Thornton (JTT) model gamma distributed with invariant sites [35]. A discrete gamma distribution was used to model evolutionary-rate differences among sites [5 categories]. The analysis involved 44 sequences. All positions with less than 95% site coverage were eliminated so that there was a total of 55 positions in the final dataset. Evolutionary analysis was conducted in MEGA6 using 500 bootstrap pseudoreplications [35].

https://doi.org/10.1371/journal.pntd.0005660.g001

SFSV and SFNV were first isolated from the sera of sick soldiers in Egypt in 1943 and Naples in 1944, respectively [3]. TOSV was first isolated in the Tuscany region of central Italy from P. perniciosus and P. perfiliewi in 1971 and 12 years later was detected in the central nervous system (CNS) of patients with meningitis [3]. Because of the geographic spread of TOSV in southern Europe and surrounding countries and the growing number of human cases [36], TOSV is recognized as an emerging pathogen and one of the most common causes of summer meningitis in the Mediterranean Basin.

On the basis of sequence analysis of the M RNA segment, different clusters of TOSV were clearly distinguished and named TOSV lineages A, B, and C (S1 Table).

The reservoir hosts

Reservoirs of Leishmania

The ecological system in which Leishmania is maintained is composed of vector and vertebrate reservoirs [4]. Usually, there is 1 principal reservoir host, which differs on the basis of the Leishmania infecting species and the infection focus (Table 3). Other susceptible mammals may become infected as minor or incidental hosts. Minor hosts may play a role in parasite maintenance, while incidental hosts are infected mammals without this role.

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Table 3. Transmission cycle, geographical distribution, and proven/suspected reservoirs of Leishmania in the Mediterranean region.

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Humans.

Humans are directly involved as principal reservoir hosts in VL caused by L. donovani and CL caused by L. tropica [4]. While the role of patients with clinical symptoms as reservoirs is clear, the role of asymptomatically infected individuals in the transmission of infection is currently unknown. Asymptomatic carriers exhibit low parasitemia, thus being less infective than symptomatic individuals [4]. Nevertheless, the huge numbers of asymptomatically infected individuals constitute a possible source of infection [37].

Animals.

Wild or domestic animals are the main reservoirs of L. infantum and L. major. Recently, some animal species have been implicated as reservoirs for L. tropica [4, 6, 3840] (Table 3).

Domestic dogs (Canis lupus familiaris) are the primary domestic reservoir hosts of L. infantum. After infection, dogs may show clinical manifestations with widespread dissemination of parasites both in viscera and dermis, making this animal an excellent source of infection for vectors; infection efficiency for sand flies increases with the increasing clinical severity [51]. Nevertheless, asymptomatic seropositive dogs may play a role in infection maintenance in the domestic transmission cycle [51].

The epidemiological role of other domestic animals, such as cats (Felis catus), is still controversial [42], while evidence of infection with L. infantum in Mediterranean wildlife has been reported in a range of carnivores, rodents, and lagomorphs [52].

Between 2009 and 2012, an outbreak of human leishmaniasis caused by L. infantum occurred in Madrid with 446 cases [53]; hares were identified as the reservoir of Leishmania during the epidemic. In fact, no increase in Leishmania seroprevalence was observed in dogs during the human outbreak, while a high number of asymptomatic Iberian hares (Lepus granatensis) infected with L. infantum were found [44]. The demonstration that naturally infected hares can transmit parasites to sand flies combined with molecular and ecoepidemiological data infers that Iberian hares can be considered as wild reservoirs of Leishmania in Spain [44].

L. major mainly causes a zoonotic infection, with infected wild rodents regarded as reservoirs [54] (Table 3). In the Mediterranean Basin, the main reservoir species is the fat sand rat (Psammomys obesus), a rodent that is very abundant in arid pre-Saharan areas, from Mauritania to the Middle East. In addition, gerbils (Meriones spp.) play a role in the maintenance of the circulation of L. major. Among the others, Meriones shawi is the reservoir host of L. major in some parts of Tunisia, Morocco, and Algeria [13], while M. tristrami and M. guentheri are suspected as the main reservoir hosts of L. major in a focus of human CL in Israel [46]. The epidemiology and control strategies of human leishmaniasis largely depend on the distribution and abundance of these rodents, which in turn are influenced by agricultural development and ecological changes. Migratory habits of some rodent species (i.e., Meriones spp.) could also contribute to the spread of L. major from endemic foci towards neighboring areas [13]. In addition, other mammals can be involved in the maintenance of the transmission cycle of L. major; natural infection in 2 species of hedgehogs (Ateleris algirus and Paraechinus aethiopicus) was recently reported from Algeria, suggesting their involvement in the parasite cycle [47].

Reservoirs of phleboviruses

No reservoir host has been defined with certainty for phleboviruses. Concerning TOSV infection, it is unlikely that humans play this role because of the transient viremia occurring in infected patients [36]; competent sand fly species might act as reservoirs in the viral cycle [6, 55, 56]. In support of this hypothesis, male sand flies were found to be infected by TOSV in nature, while transovarial transmission was experimentally demonstrated as well as venereal transmission from infected P. pernicious males to uninfected females. However, the progressive decrease in viral infection rates observed from generation to generation in sand fly colonies suggests that TOSV cannot be maintained indefinitely by vertical or venereal transmission [6]. Consequently, the existence of additional reservoirs should be considered.

Only a few studies were conducted on animals to verify their role as reservoirs of phleboviruses. In 1984, TOSV was isolated from a bat in Italy, while the high frequency of viral RNA and specific antibodies for TOSV in the canine population in Tunisia and Turkey suggests that dogs can act as TOSV reservoirs [57, 58]. However, this merits further exploration in other geographic areas and through experimental studies. TOSV antibodies were also revealed in horses, cats, dogs, sheep, pigs, cows, and goats in Spain [59] and in dogs living in Corsica [60] and Algeria [61]. Although there is no direct evidence for infection of vertebrates by sand fly–borne phleboviruses other than TOSV, high rates of neutralizing antibodies in various mammals demonstrate high exposure to phleboviruses in Tunisia and Turkey [32, 58].

Human infection caused by phlebotomine sand fly–borne pathogens in the Mediterranean Basin

Clinical syndromes caused by sand fly–borne pathogens are only the tip of the iceberg; asymptomatic infected carriers are frequent and likely more abundant in rural areas, where vectors are numerous [37]. Human seroprevalence for Leishmania and Phlebovirus in the countries of the Mediterranean Basin is reported in S2 Table.

The clinical spectrum of human leishmaniasis ranges from asymptomatic infection to 3 main clinical syndromes: VL, CL, and mucosal leishmaniasis (ML) [4]. Clinical manifestations are the result of the relationship between the leishmanial species and the host and are partially dependent on strain differences, making some species more adapted to target the skin and others to invade visceral organs [62]. VL is the most severe form of the disease, and it is fatal if untreated; the target organs of VL are the spleen, the liver, the bone marrow, and the lymph nodes, where parasites proliferate in the cells of the mononuclear phagocytic system [4, 63]. CL is characterized by single or multiple ulcerative or nodular lesions in exposed areas of the body; L. tropica mainly causes a single lesion, while L. major is often characterized by multiple lesions [5, 64]. ML pathophysiology in the Mediterranean region remains unclear as it is usually not associated with previous CL [65]. The most frequent localizations are larynx, pharynx, mouth, and nose, and the lesions are polypoid, infiltrative, ulcerative, or nodular [6569].

SFSV and SFNV cause a typical “3-day fever” or “pappataci fever,” while TOSV displays a strong neurotropism responsible for acute meningitis and meningoencephalitis [36]. Nevertheless, most cases of TOSV infection present as asymptomatic cases or as a flu-like syndrome [70]. In addition, an outbreak of febrile syndrome was observed in Greek soldiers stationed in Cyprus in 2002; molecular investigation confirmed the presence of a new phlebovirus provisionally named Sandfly fever Cyprus virus [71]. Finally, Adria virus was detected in the blood of a Greek child with febrile seizure [72] and Sandfly fever Turkey virus was isolated from the cerebrospinal fluid of a Turkish patient with encephalitis [73].

Fig 2 and Table 4 report the distribution of human infections caused by Leishmania and phleboviruses in the Mediterranean region.

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Fig 2. Distribution of human infections caused by sand fly–transmitted pathogens in the Mediterranean region using spatial methods.

(a) Autochthonous human leishmaniasis in the Mediterranean area. Countries where human leishmaniasis was diagnosed by serological tests and/or Leishmania isolation and/or PCR method are depicted in yellow. Diagrams show Leishmania species identified and/or isolated in human cases. (b) Autochthonous human phlebovirus infection in the Mediterranean area. Countries where human phlebovirus infection was diagnosed by serological tests and/or Phlebovirus isolation and/or PCR method are depicted in yellow, while white areas represent countries where human phlebovirus infection was never observed. Diagrams show Phlebovirus species identified and/or isolated in human cases; where no diagram is present, identification of phleboviruses species was not performed. Maps were created using the open source software, QGIS 2.12.

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Table 4. Distribution of Leishmania and Phlebovirus responsible for human infection in Mediterranean region countries.

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Effect of global changes on phlebotomine sand fly–borne pathogens

Environmental aspects such as climate change, increasing urbanization, economic development, and population movements for economic, social, or political reasons are causing changes in the epidemiology of vector-borne infections, as they lead to alteration in the range of vectors, reservoirs, and pathogens [4].

Man-made ecological changes including urbanization, spread of agriculture into semiarid lands, and the introduction of artificial irrigation systems can affect the incidence of sand flies [4, 110, 111]. Other human activities, such as tourism and pilgrimages from or to endemic areas, may contribute to the spread of exotic pathogens to areas that are already endemic for other sand fly–borne pathogens.

In disadvantaged areas, other factors contribute to the diffusion of sand fly–borne diseases. For example, poor domestic and peridomestic sanitary conditions may attract anthropophilic sand flies and may increase breeding sites of the vectors, while malnutrition and high incidence of HIV infection may result in inadequate immune response and higher clinical expression of infections.

In conflict areas, lack of or destruction of healthcare infrastructures may occur as well as massive population displacement, the latter potentially causing the introduction of nonimmune people into areas with endemic/enzootic disease or the emergence of pathogens in areas where infected individuals are displaced and where reservoirs and vectors coexist. As the most recent example, the Syrian refugee crisis has precipitated a catastrophic outbreak of CL, leading to hundreds of thousands of CL-affected people living in refugee camps in Lebanon or trapped in conflict zones [112]. The exodus of migrants from Syria has led to a dramatic increase of CL cases in southern Turkey and to the introduction of new leishmanial species, such as L. major [50]. Similar situations may also be unfolding in other conflict areas, such as Libya and Yemen [112].

Although different factors may influence the diffusion of sand fly–borne diseases, the range and density of vectors are considered the most important risk factors for the emergence of leishmaniasis and phlebovirus diseases in Mediterranean and continental Europe [14, 113]. The recent geographical expansion of phlebotomine vectors in the Mediterranean region has been attributed to ongoing climate changes and investigation on seasonal dynamics of vectors for L. infantum in Mediterranean Europe confirmed that temperature is a major determinant for the seasonal interval of sand fly activity [114]. Thus, global warming can affect the diffusion of sand flies and sand fly–borne diseases, as shown by the detection of sand flies in continental Europe, including Germany, Austria, Switzerland, and Slovakia [113, 115117] and by the northward spread of leishmaniasis in Italy, respectively [6]. In addition, large areas of continental Europe that are unsuitable for sand fly species today are projected to change towards a climate that will support the survival and replication of these vectors [113].

Factors other than vector density can influence the presence and diffusion of sand fly–borne pathogens, including the replication rate of the pathogen, the vector biting rate, and host and reservoir availability [113]. Climate changes, indeed, can also influence the development cycle of Leishmania promastigotes in sand flies; increases in minimum temperature accelerate the parasitic life cycle [113, 118].

Conclusions

Sand fly–borne pathogens such as Leishmania spp. and phleboviruses are currently emerging in southern Europe, posing a complex threat to human health. A number of factors can influence the epidemiology of sand fly–transmitted infections, including environmental and climate changes, poverty, mass migration, and conflicts. Concerning the spreading of Leishmania, changes in infected animal reservoirs are also important; the northward spread of human leishmaniasis in Italy following the detection of infected dogs in the northern part of the country as well as the recent outbreak in Spain with hares as reservoirs show that hosts play a major role in transmission cycle under changing conditions.

Our review highlights the fact that, despite their emergence, several aspects of the epidemiology of phlebotomine sand fly–borne infections are poorly studied. Among others, there is an urgent need for increased public health activities to ameliorate the surveillance of sand fly–borne infections, considering that underreporting of VL and CL is observed in countries with a compulsory notification system for leishmaniasis [119] and Phlebovirus infection are not subjected to notification. Diagnostic tools should also be implemented, focusing on molecular tests for rapid pathogen detection, while studies on the potential role of domestic and wild mammals as reservoir hosts should be carried out as well as continuous surveillance of canine leishmaniasis. There is also a need to continuously monitor vector distribution in endemic as well as nonendemic countries—activities that are so far scarce and scattered—with in-depth investigation into the vectorial capacity of the sand fly species identified in different areas. 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.

Key learning points

  • Pathogens transmitted to humans by phlebotomine sand flies such as Leishmania spp. and phleboviruses are currently emerging in southern Europe.
  • Evidence of Leishmania hybrid strains suggests that the exchange of genetic material can occur in these parasites.
  • Genomic data on newly detected sand fly–borne phleboviruses are available, which allows the development of novel molecular tests to evaluate the role of these viruses in human pathology.
  • A number of environmental factors such as climate change, increasing urbanization, economic development, and population movements are causing changes in the epidemiology of sand flyborne infections as the result of altering the accessible range of vectors, reservoirs, and pathogens.
  • Massive population displacement from conflict areas can cause the introduction of nonimmune people into areas with endemic/enzootic disease or the emergence of pathogens in areas where infected individuals are displaced and where reservoirs and vectors coexist.

Top 5 papers

  1. Alvar J, Vélez ID, Bern C, Herrero M, Desjeux P, Cano J, et al. Leishmaniasis worldwide and global estimates of its incidence. PLoS ONE. 2012;7(5):e35671.
  2. Alkan C, Bichaud L, de Lamballerie X, Alten B, Gould EA, Charrel RN. Sandfly-borne phleboviruses of Eurasia and Africa: epidemiology, genetic diversity, geographic range, control measures. Antiviral Res. 2013;100(1):54–74.
  3. Dujardin JC, Campino L, Cañavate C, Dedet JP, Gradoni L, Soteriadou K, et al. Spread of vector-borne diseases and neglect of Leishmaniasis, Europe. Emerg Infect Dis. 2008;14(7):1013–8.
  4. Gradoni L. Epidemiological surveillance of leishmaniasis in the European Union: operational and research challenges. Euro Surveill. 2013;18(30):20539.
  5. Depaquit J, Grandadam M, Fouque F, Andry PE, Peyrefitte C. Arthropod-borne viruses transmitted by Phlebotomine sand flies in Europe: a review. Euro Surveill. 2010 Mar;15(10):19507. PubMed PMID: 20403307. eng.

Supporting information

S1 Table. TOSV lineage distribution in the Mediterranean region.

https://doi.org/10.1371/journal.pntd.0005660.s001

(DOCX)

S2 Table. Human seroprevalence of Leishmania and phleboviruses in the Mediterranean region.

https://doi.org/10.1371/journal.pntd.0005660.s002

(DOCX)

Acknowledgments

We thank Professor Ernest A. Gould for critical revision.

References

  1. 1. Dujardin JC, Campino L, Cañavate C, Dedet JP, Gradoni L, Soteriadou K, et al. Spread of vector-borne diseases and neglect of Leishmaniasis, Europe. Emerg Infect Dis. 2008;14(7):1013–8. pmid:18598618
  2. 2. Alvar J, Vélez ID, Bern C, Herrero M, Desjeux P, Cano J, et al. Leishmaniasis worldwide and global estimates of its incidence. PLoS ONE. 2012;7(5):e35671. pmid:22693548
  3. 3. Alkan C, Bichaud L, de Lamballerie X, Alten B, Gould EA, Charrel RN. Sandfly-borne phleboviruses of Eurasia and Africa: epidemiology, genetic diversity, geographic range, control measures. Antiviral Res. 2013;100(1):54–74. pmid:23872312
  4. 4. WHO. Control of the leishmaniases: report of a meeting of the WHO Expert Committee on the Control of Leishmaniases, Geneva, 22–26 March 2010. 2010.
  5. 5. Van der Auwera G, Dujardin JC. Species typing in dermal leishmaniasis. Clin Microbiol Rev. 2015;28(2):265–94. pmid:25672782
  6. 6. Maroli M, Feliciangeli MD, Bichaud L, Charrel RN, Gradoni L. Phlebotomine sandflies and the spreading of leishmaniases and other diseases of public health concern. Med Vet Entomol. 2013;27(2):123–47. pmid:22924419
  7. 7. Svobodová M, Alten B, Zídková L, Dvorák V, Hlavacková J, Mysková J, et al. Cutaneous leishmaniasis caused by Leishmania infantum transmitted by Phlebotomus tobbi. Int J Parasitol. 2009;39(2):251–6. pmid:18761342
  8. 8. Gouzelou E, Haralambous C, Amro A, Mentis A, Pratlong F, Dedet JP, et al. Multilocus microsatellite typing (MLMT) of strains from Turkey and Cyprus reveals a novel monophyletic L. donovani sensu lato group. PLoS Negl Trop Dis. 2012;6(2):e1507. pmid:22348162
  9. 9. Rogers MB, Downing T, Smith BA, Imamura H, Sanders M, Svobodova M, et al. Genomic confirmation of hybridisation and recent inbreeding in a vector-isolated Leishmania population. PLoS Genet. 2014;10(1):e1004092. pmid:24453988
  10. 10. Jamjoom MB, Ashford RW, Bates PA, Chance ML, Kemp SJ, Watts PC, et al. Leishmania donovani is the only cause of visceral leishmaniasis in East Africa; previous descriptions of L. infantum and "L. archibaldi" from this region are a consequence of convergent evolution in the isoenzyme data. Parasitology. 2004;129(Pt 4):399–409. pmid:15521628
  11. 11. Pratlong F, Lami P, Ravel C, Balard Y, Dereure J, Serres G, et al. Geographical distribution and epidemiological features of Old World Leishmania infantum and Leishmania donovani foci, based on the isoenzyme analysis of 2277 strains. Parasitology. 2013;140(4):423–34. pmid:23146283
  12. 12. El Baidouri F, Diancourt L, Berry V, Chevenet F, Pratlong F, Marty P, et al. Genetic structure and evolution of the Leishmania genus in Africa and Eurasia: what does MLSA tell us. PLoS Negl Trop Dis. 2013;7(6):e2255. pmid:23785530
  13. 13. Ghawar W, Toumi A, Snoussi MA, Chlif S, Zâatour A, Boukthir A, et al. Leishmania major infection among Psammomys obesus and Meriones shawi: reservoirs of zoonotic cutaneous leishmaniasis in Sidi Bouzid(central Tunisia). Vector Borne Zoonotic Dis. 2011;11(12):1561–8. pmid:21919726
  14. 14. Ready PD. Leishmaniasis emergence in Europe. Euro Surveill. 2010;15(10):19505. pmid:20403308
  15. 15. Seblova V, Myskova J, Hlavacova J, Votypka J, Antoniou M, Volf P. Natural hybrid of Leishmania infantum/L. donovani: development in Phlebotomus tobbi, P. perniciosus and Lutzomyia longipalpis and comparison with non-hybrid strains differing in tissue tropism. Parasit Vectors. 2015;8:605. pmid:26608249
  16. 16. Garifallou A, Schnur LF, Stratigos JD, Hadziandoniou M, Savigos M, Stavrianeas N, et al. Leishmaniasis in Greece II. Isolation and identification of the parasite causing cutaneous leishmaniasis in man. Ann Trop Med Parasitol. 1984;78(4):369–75. pmid:6433815
  17. 17. Ntais P, Sifaki-Pistola D, Christodoulou V, Messaritakis I, Pratlong F, Poupalos G, et al. Leishmaniases in Greece. Am J Trop Med Hyg. 2013;89(5):906–15. pmid:24062479
  18. 18. Antoniou M, Haralambous C, Mazeris A, Pratlong F, Dedet JP, Soteriadou K. Leishmania donovani leishmaniasis in Cyprus. Lancet Infect Dis. 2008;8(1):6–7. pmid:18156082
  19. 19. Alam MZ, Haralambous C, Kuhls K, Gouzelou E, Sgouras D, Soteriadou K, et al. The paraphyletic composition of Leishmania donovani zymodeme MON-37 revealed by multilocus microsatellite typing. Microbes Infect. 2009;11(6–7):707–15. pmid:19376262
  20. 20. Ravel C, Cortes S, Pratlong F, Morio F, Dedet JP, Campino L. First report of genetic hybrids between two very divergent Leishmania species: Leishmania infantum and Leishmania major. Int J Parasitol. 2006;36(13):1383–8. pmid:16930606
  21. 21. Nolder D, Roncal N, Davies CR, Llanos-Cuentas A, Miles MA. Multiple hybrid genotypes of Leishmania (viannia) in a focus of mucocutaneous Leishmaniasis. Am J Trop Med Hyg. 2007;76(3):573–8. pmid:17360886
  22. 22. Volf P, Benkova I, Myskova J, Sadlova J, Campino L, Ravel C. Increased transmission potential of Leishmania major/Leishmania infantum hybrids. Int J Parasitol. 2007;37(6):589–93. pmid:17376453
  23. 23. Plyusnin A, Beaty BJ, Elliott RM, Goldbach R, Kormelink R, Lundkvist A, et al. Bunyaviridae. In Virus taxonomy: classification and nomenclature of viruses. Ninth Report of the International Committee on Taxonomy of Viruses.: Elsevier Academic Press, San Diego, CA; 2012. p. 693–709.
  24. 24. Palacios G, Tesh RB, Savji N, Travassos da Rosa AP, Guzman H, Bussetti AV, et al. Characterization of the Sandfly fever Naples species complex and description of a new Karimabad species complex (genus Phlebovirus, family Bunyaviridae). J Gen Virol. 2014;95(Pt 2):292–300. pmid:24096318
  25. 25. Remoli ME, Fortuna C, Marchi A, Bucci P, Argentini C, Bongiorno G, et al. Viral isolates of a novel putative phlebovirus in the Marche Region of Italy. Am J Trop Med Hyg. 2014;90(4):760–3. pmid:24534812
  26. 26. Fares W, Charrel RN, Dachraoui K, Bichaud L, Barhoumi W, Derbali M, et al. Infection of sand flies collected from different bio-geographical areas of Tunisia with phleboviruses. Acta Trop. 2015;141(Pt A):1–6. pmid:25255967
  27. 27. Amaro F, Hanke D, Zé-Zé L, Alves MJ, Becker SC, Höper D. Genetic characterization of Arrabida virus, a novel phlebovirus isolated in South Portugal. Virus Res. 2016;214:19–25. pmid:26795868
  28. 28. Alkan C, Erisoz Kasap O, Alten B, de Lamballerie X, Charrel RN. Sandfly-Borne Phlebovirus Isolations from Turkey: New Insight into the Sandfly fever Sicilian and Sandfly fever Naples Species. PLoS Negl Trop Dis. 2016;10(3):e0004519. pmid:27007326
  29. 29. Palacios G, Savji N, Travassos da Rosa A, Desai A, Sanchez-Seco MP, Guzman H, et al. Characterization of the Salehabad virus species complex of the genus Phlebovirus (Bunyaviridae). J Gen Virol. 2013;94(Pt 4):837–42. pmid:23239568
  30. 30. Amaro F, Zé-Zé L, Alves MJ, Börstler J, Clos J, Lorenzen S, et al. Co-circulation of a novel phlebovirus and Massilia virus in sandflies, Portugal. Virol J. 2015;12(1):174.
  31. 31. Ergunay K, Kasap OE, Orsten S, Oter K, Gunay F, Yoldar AZ, et al. Phlebovirus and Leishmania detection in sandflies from eastern Thrace and northern Cyprus. Parasit Vectors. 2014;7:575. pmid:25499083
  32. 32. Alkan C, Alwassouf S, Piorkowski G, Bichaud L, Tezcan S, Dincer E, et al. Isolation, genetic characterization, and seroprevalence of Adana virus, a novel phlebovirus belonging to the Salehabad virus complex, in Turkey. J Virol. 2015;89(8):4080–91. pmid:25653443
  33. 33. Bichaud L, Dachraoui K, Alwassouf S, Alkan C, Mensi M, Piorkowski G, et al. Isolation, full genomic characterisation and neutralisation-based human seroprevalence of Medjerda Valley virus, a novel sandfly-borne phlebovirus belonging to the Salehabad virus complex in northern Tunisia. J Gen Virol. 2015.
  34. 34. Peyrefitte CN, Grandadam M, Bessaud M, Andry PE, Fouque F, Caro V, et al. Diversity of Phlebotomus perniciosus in Provence, southeastern France: Detection of two putative new phlebovirus sequences. Vector Borne Zoonotic Dis. 2013;13(9):630–6. pmid:23705585
  35. 35. Tamura K, Stecher G, Peterson D, Filipski A, Kumar S. MEGA6: Molecular Evolutionary Genetics Analysis version 6.0. Mol Biol Evol. 2013;30(12):2725–9. pmid:24132122
  36. 36. Depaquit J, Grandadam M, Fouque F, Andry PE, Peyrefitte C. Arthropod-borne viruses transmitted by Phlebotomine sandflies in Europe: a review. Euro Surveill. 2010;15(10):19507. pmid:20403307
  37. 37. Michel G, Pomares C, Ferrua B, Marty P. Importance of worldwide asymptomatic carriers of Leishmania infantum (L. chagasi) in human. Acta Trop. 2011;119(2–3):69–75. pmid:21679680
  38. 38. Jacobson RL. Leishmania tropica (Kinetoplastida: Trypanosomatidae)—a perplexing parasite. Folia Parasitol (Praha). 2003;50(4):241–50.
  39. 39. Svobodova M, Votypka J, Peckova J, Dvorak V, Nasereddin A, Baneth G, et al. Distinct transmission cycles of Leishmania tropica in 2 adjacent foci, Northern Israel. Emerg Infect Dis. 2006;12(12):1860–8. pmid:17326936
  40. 40. Talmi-Frank D, Jaffe CL, Nasereddin A, Warburg A, King R, Svobodova M, et al. Leishmania tropica in rock hyraxes (Procavia capensis) in a focus of human cutaneous leishmaniasis. Am J Trop Med Hyg. 2010;82(5):814–8. pmid:20439960
  41. 41. Dantas-Torres F. The role of dogs as reservoirs of Leishmania parasites, with emphasis on Leishmania (Leishmania) infantum and Leishmania (Viannia) braziliensis. Vet Parasitol. 2007;149(3–4):139–46. pmid:17703890
  42. 42. Pennisi MG, Hartmann K, Lloret A, Addie D, Belák S, Boucraut-Baralon C, et al. Leishmaniosis in cats: ABCD guidelines on prevention and management. J Feline Med Surg. 2013;15(7):638–42. pmid:23813831
  43. 43. Navea-Pérez HM, Díaz-Sáez V, Corpas-López V, Merino-Espinosa G, Morillas-Márquez F, Martín-Sánchez J. Leishmania infantum in wild rodents: reservoirs or just irrelevant incidental hosts? Parasitol Res. 2015;114(6):2363–70. pmid:25797596
  44. 44. Molina R, Jiménez MI, Cruz I, Iriso A, Martín-Martín I, Sevillano O, et al. The hare (Lepus granatensis) as potential sylvatic reservoir of Leishmania infantum in Spain. Vet Parasitol. 2012;190(1–2):268–71. pmid:22677135
  45. 45. Jiménez M, González E, Martín-Martín I, Hernández S, Molina R. Could wild rabbits (Oryctolagus cuniculus) be reservoirs for Leishmania infantum in the focus of Madrid, Spain? Vet Parasitol. 2014;202(3–4):296–300. pmid:24774435
  46. 46. Faiman R, Abbasi I, Jaffe C, Motro Y, Nasereddin A, Schnur LF, et al. A newly emerged cutaneous leishmaniasis focus in northern Israel and two new reservoir hosts of Leishmania major. PLoS Negl Trop Dis. 2013;7(2):e2058. pmid:23437408
  47. 47. Tomás-Pérez M, Khaldi M, Riera C, Mozo-León D, Ribas A, Hide M, et al. First report of natural infection in hedgehogs with Leishmania major, a possible reservoir of zoonotic cutaneous leishmaniasis in Algeria. Acta Trop. 2014;135:44–9. pmid:24699087
  48. 48. Paşa S, Tetik Vardarlı A, Erol N, Karakuş M, Töz S, Atasoy A, et al. Detection of Leishmania major and Leishmania tropica in domestic cats in the Ege Region of Turkey. Vet Parasitol. 2015;212(3–4):389–92. pmid:26277567
  49. 49. Bousslimi N, Ben-Ayed S, Ben-Abda I, Aoun K, Bouratbine A. Natural infection of North African gundi (Ctenodactylus gundi) by Leishmania tropica in the focus of cutaneous leishmaniasis, Southeast Tunisia. Am J Trop Med Hyg. 2012;86(6):962–5. pmid:22665601
  50. 50. Koltas IS, Eroglu F, Alabaz D, Uzun S. The emergence of Leishmania major and Leishmania donovani in southern Turkey. Trans R Soc Trop Med Hyg. 2014;108(3):154–8. pmid:24449479
  51. 51. Quinnell RJ, Courtenay O. Transmission, reservoir hosts and control of zoonotic visceral leishmaniasis. Parasitology. 2009;136(14):1915–34. pmid:19835643
  52. 52. Millán J, Ferroglio E, Solano-Gallego L. Role of wildlife in the epidemiology of Leishmania infantum infection in Europe. Parasitol Res. 2014;113(6):2005–14. pmid:24804923
  53. 53. Arce A, Estirado A, Ordobas M, Sevilla S, García N, Moratilla L, et al. Re-emergence of leishmaniasis in Spain: community outbreak in Madrid, Spain, 2009 to 2012. Euro Surveill. 2013;18(30):20546. pmid:23929177
  54. 54. Azizi K, Moemenbellah-Fard MD, Kalantari M, Fakoorziba MR. Molecular detection of Leishmania major kDNA from wild rodents in a new focus of zoonotic cutaneous leishmaniasis in an Oriental region of Iran. Vector Borne Zoonotic Dis. 2012;12(10):844–50. pmid:22651390
  55. 55. Maroli M, Ciufolini MG, Verani P. Vertical transmission of Toscana virus in the sandfly, Phlebotomus perniciosus, via the second gonotrophic cycle. Med Vet Entomol. 1993;7(3):283–6. pmid:8369564
  56. 56. Tesh RB, Modi GB. Maintenance of Toscana virus in Phlebotomus perniciosus by vertical transmission. Am J Trop Med Hyg. 1987;36(1):189–93. pmid:3028194
  57. 57. Dincer E, Gargari S, Ozkul A, Ergunay K. Potential animal reservoirs of Toscana virus and coinfections with Leishmania infantum in Turkey. Am J Trop Med Hyg. 2015;92(4):690–7. pmid:25711610
  58. 58. Sakhria S, Alwassouf S, Fares W, Bichaud L, Dachraoui K, Alkan C, et al. Presence of sandfly-borne phleboviruses of two antigenic complexes (Sandfly fever Naples virus and Sandfly fever Sicilian virus) in two different bio-geographical regions of Tunisia demonstrated by a microneutralisation-based seroprevalence study in dogs. Parasit Vectors. 2014;7:476. pmid:25306250
  59. 59. Navarro-Marí JM, Palop-Borrás B, Pérez-Ruiz M, Sanbonmatsu-Gámez S. Serosurvey study of Toscana virus in domestic animals, Granada, Spain. Vector Borne Zoonotic Dis. 2011;11(5):583–7. pmid:20925529
  60. 60. Dahmani M, Alwassouf S, Grech-Angelini S, Marié JL, Davoust B, Charrel RN. Seroprevalence of Toscana virus in dogs from Corsica, France. Parasit Vectors. 2016;9(1):381. pmid:27368162
  61. 61. Tahir D, Alwassouf S, Loudahi A, Davoust B, Charrel RN. Seroprevalence of Toscana virus in dogs from Kabylia (Algeria). Clin Microbiol Infect. 2016;22(3):e16–7. pmid:26551844
  62. 62. McCall LI, Zhang WW, Matlashewski G. Determinants for the development of visceral leishmaniasis disease. PLoS Pathog. 2013;9(1):e1003053. pmid:23300451
  63. 63. Chappuis F, Sundar S, Hailu A, Ghalib H, Rijal S, Peeling RW, et al. Visceral leishmaniasis: what are the needs for diagnosis, treatment and control? Nat Rev Microbiol. 2007;5(11):873–82. pmid:17938629
  64. 64. Al-Jawabreh A, Dumaidi K, Ereqat S, Al-Jawabreh H, Nasereddin A, Azmi K, et al. Molecular epidemiology of human cutaneous leishmaniasis in Jericho and its vicinity in Palestine from 1994 to 2015. Infect Genet Evol. 2017;50:95–101. pmid:27268151
  65. 65. Faucher B, Pomares C, Fourcade S, Benyamine A, Marty P, Pratlong L, et al. Mucosal Leishmania infantum leishmaniasis: specific pattern in a multicentre survey and historical cases. J Infect. 2011;63(1):76–82. pmid:21658772
  66. 66. Aliaga L, Cobo F, Mediavilla JD, Bravo J, Osuna A, Amador JM, et al. Localized mucosal leishmaniasis due to Leishmania (Leishmania) infantum: clinical and microbiologic findings in 31 patients. Medicine (Baltimore). 2003;82(3):147–58.
  67. 67. Richter J, Hanus I, Häussinger D, Löscher T, Harms G. Mucosal Leishmania infantum infection. Parasitol Res. 2011;109(3):959–62. pmid:21499751
  68. 68. Mignogna MD, Celentano A, Leuci S, Cascone M, Adamo D, Ruoppo E, et al. Mucosal leishmaniasis with primary oral involvement: a case series and a review of the literature. Oral Dis. 2015;21(1):e70–8. pmid:24939442
  69. 69. Mosimann V, Blazek C, Grob H, Chaney M, Neumayr A, Blum J. Miltefosine for Mucosal and Complicated Cutaneous Old World Leishmaniasis: A Case Series and Review of the Literature. Open Forum Infect Dis. 2016;3(1):ofw008. pmid:27042675
  70. 70. Braito A, Corbisiero R, Corradini S, Marchi B, Sancasciani N, Fiorentini C, et al. Evidence of Toscana virus infections without central nervous system involvement: a serological study. Eur J Epidemiol. 1997;13(7):761–4. pmid:9384264
  71. 71. Papa A, Konstantinou G, Pavlidou V, Antoniadis A. Sandfly fever virus outbreak in Cyprus. Clin Microbiol Infect. 2006;12(2):192–4. pmid:16441462
  72. 72. Anagnostou V, Pardalos G, Athanasiou-Metaxa M, Papa A. Novel phlebovirus in febrile child, Greece. Emerg Infect Dis. 2011;17(5):940–1. pmid:21529422
  73. 73. Ergunay K, Ismayilova V, Colpak IA, Kansu T, Us D. A case of central nervous system infection due to a novel Sandfly Fever Virus (SFV) variant: Sandfly Fever Turkey Virus (SFTV). J Clin Virol. 2012;54(1):79–82. pmid:22336084
  74. 74. Campino L, Pratlong F, Abranches P, Rioux JA, Santos-Gomes G, Alves-Pires C, et al. Leishmaniasis in Portugal: enzyme polymorphism of Leishmania infantum based on the identification of 213 strains. Trop Med Int Health. 2006;11(11):1708–14. pmid:17054751
  75. 75. Santos L, Simões J, Costa R, Martins S, Lecour H. Toscana virus meningitis in Portugal, 2002–2005. Euro Surveill. 2007;12(6):E3–4. pmid:17991401
  76. 76. Suárez Rodríguez B, Isidoro Fernández B, Santos Sanz S, Sierra Moros MJ, Molina Moreno R, Astray Mochales J, et al. [Review of the current situation and the risk factors of Leishmania infantum in Spain]. Rev Esp Salud Publica. 2012;86(6):555–64. pmid:23325131
  77. 77. Mendoza-Montero J, Gámez-Rueda MI, Navarro-Marí JM, de la Rosa-Fraile M, Oyonarte-Gómez S. Infections due to sandfly fever virus serotype Toscana in Spain. Clin Infect Dis. 1998;27(3):434–6. pmid:9770137
  78. 78. Pratlong F, Rioux JA, Marty P, Faraut-Gambarelli F, Dereure J, Lanotte G, et al. Isoenzymatic analysis of 712 strains of Leishmania infantum in the south of France and relationship of enzymatic polymorphism to clinical and epidemiological features. J Clin Microbiol. 2004;42(9):4077–82. pmid:15364993
  79. 79. Dupouey J, Bichaud L, Ninove L, Zandotti C, Thirion-Perrier L, de Lamballerie X, et al. Toscana virus infections: a case series from France. J Infect. 2014;68(3):290–5. pmid:24247068
  80. 80. Gramiccia M, Scalone A, Di Muccio T, Orsini S, Fiorentino E, Gradoni L. The burden of visceral leishmaniasis in Italy from 1982 to 2012: a retrospective analysis of the multi-annual epidemic that occurred from 1989 to 2009. Euro Surveill. 2013;18(29):20535. pmid:23929120
  81. 81. Nicoletti L, Verani P, Caciolli S, Ciufolini MG, Renzi A, Bartolozzi D, et al. Central nervous system involvement during infection by Phlebovirus toscana of residents in natural foci in central Italy (1977–1988). Am J Trop Med Hyg. 1991;45(4):429–34. pmid:1951851
  82. 82. Gkolfinopoulou K, Bitsolas N, Patrinos S, Veneti L, Marka A, Dougas G, et al. Epidemiology of human leishmaniasis in Greece, 1981–2011. Euro Surveill. 2013;18(29):20532. pmid:23929118
  83. 83. Papa A, Paraforou T, Papakonstantinou I, Pagdatoglou K, Kontana A, Koukoubani T. Severe encephalitis caused by Toscana virus, Greece. Emerg Infect Dis. 2014;20(8):1417–9. pmid:25061909
  84. 84. Punda-Polić V, Mohar B, Duh D, Bradarić N, Korva M, Fajs L, et al. Evidence of an autochthonous Toscana virus strain in Croatia. J Clin Virol. 2012;55(1):4–7. pmid:22795597
  85. 85. Hukić M, Salimović-Besić I. Sandfly—Pappataci fever in Bosnia and Herzegovina: the new-old disease. Bosn J Basic Med Sci. 2009;9(1):39–43. pmid:19284393
  86. 86. Mazeris A, Soteriadou K, Dedet JP, Haralambous C, Tsatsaris A, Moschandreas J, et al. Leishmaniases and the Cyprus paradox. Am J Trop Med Hyg. 2010;82(3):441–8. pmid:20207870
  87. 87. Eitrem R, Vene S, Niklasson B. Incidence of sand fly fever among Swedish United Nations soldiers on Cyprus during 1985. Am J Trop Med Hyg. 1990;43(2):207–11. pmid:2167616
  88. 88. Konstantinou GN, Papa A, Antoniadis A. Sandfly-fever outbreak in Cyprus: are phleboviruses still a health problem? Travel Med Infect Dis. 2007;5(4):239–42. pmid:17574146
  89. 89. Gradoni L, Gramiccia M, Léger N, Pesson B, Madulo-Leblond G, Killick-Kendrick R, et al. Isoenzyme characterization of Leishmania from man, dog and sandflies in the Maltese islands. Trans R Soc Trop Med Hyg. 1991;85(2):217–9. pmid:1887474
  90. 90. Schultze D, Korte W, Rafeiner P, Niedrig M. First report of sandfly fever virus infection imported from Malta into Switzerland, October 2011. Euro Surveill. 2012;17(27).
  91. 91. Toz SO, Nasereddin A, Ozbel Y, Ertabaklar H, Culha G, Sevil N, et al. Leishmaniasis in Turkey: molecular characterization of Leishmania from human and canine clinical samples. Trop Med Int Health. 2009;14(11):1401–6. pmid:19737374
  92. 92. Ergünay K, Saygan MB, Aydoğan S, Lo MM, Weidmann M, Dilcher M, et al. Sandfly fever virus activity in central/northern Anatolia, Turkey: first report of Toscana virus infections. Clin Microbiol Infect. 2011;17(4):575–81. pmid:20731683
  93. 93. Al-Nahhas S, Shaaban M, Hammoud L. Contribution study of visceral leishmaniasis in Syria. Saudi Med J. 2005;26(3):490–2. pmid:15806230
  94. 94. Hayani K, Dandashli A, Weisshaar E. Cutaneous leishmaniasis in Syria: clinical features, current status and the effects of war. Acta Derm Venereol. 2015;95(1):62–6. pmid:25342106
  95. 95. Nuwayri-Salti N, Baydoun E, Alema-Munoz MM, Kreutzer RD. Identification of Leishmania isolates from a Lebanese population. Am J Trop Med Hyg. 1994;51(1):98–101. pmid:8059921
  96. 96. Gandacu D, Glazer Y, Anis E, Karakis I, Warshavsky B, Slater P, et al. Resurgence of cutaneous leishmaniasis in Israel, 2001–2012. Emerg Infect Dis. 2014;20(10):1605–11. pmid:25271882
  97. 97. Ben-Shimol S, Sagi O, Horev A, Avni YS, Ziv M, Riesenberg K. Cutaneous leishmaniasis caused by Leishmania infantum in Southern Israel. Acta Parasitol. 2016;61(4):855–8. pmid:27787222
  98. 98. Nasereddin A, Baneth G, Schönian G, Kanaan M, Jaffe CL. Molecular fingerprinting of Leishmania infantum strains following an outbreak of visceral leishmaniasis in central Israel. J Clin Microbiol. 2005;43(12):6054–9. pmid:16333098
  99. 99. Hamarsheh O, Nasereddin A, Damaj S, Sawalha S, Al-Jawabreh H, Azmi K, et al. Serological and molecular survey of Leishmania parasites in apparently healthy dogs in the West Bank, Palestine. Parasit Vectors. 2012;5:183. pmid:22937916
  100. 100. Azmi K, Schönian G, Nasereddin A, Schnur LF, Sawalha S, Hamarsheh O, et al. Epidemiological and clinical features of cutaneous leishmaniases in Jenin District, Palestine, including characterisation of the causative agents in clinical samples. Trans R Soc Trop Med Hyg. 2012;106(9):554–62. pmid:22832019
  101. 101. Amro A, Azmi K, Schönian G, Nasereddin A, Alsharabati MB, Sawalha S, et al. Epidemiology of paediatric visceral leishmaniasis in Hebron district, Palestine. Trans R Soc Trop Med Hyg. 2009;103(7):731–6. pmid:19022464
  102. 102. Kahime K, Boussaa S, Ouanaimi F, Boumezzough A. Species composition of phlebotomine sand fly fauna in an area with sporadic cases of Leishmania infantum human visceral leishmaniasis, Morocco. Acta Trop. 2015;148:58–65. pmid:25930188
  103. 103. Aoun K, Bouratbine A. Cutaneous leishmaniasis in North Africa: a review. Parasite. 2014;21:14. pmid:24626301
  104. 104. Ben-Ahmed K, Aoun K, Jeddi F, Ghrab J, El-Aroui MA, Bouratbine A. Visceral leishmaniasis in Tunisia: spatial distribution and association with climatic factors. Am J Trop Med Hyg. 2009;81(1):40–5. pmid:19556564
  105. 105. Salah AB, Kamarianakis Y, Chlif S, Alaya NB, Prastacos P. Zoonotic cutaneous leishmaniasis in central Tunisia: spatio temporal dynamics. Int J Epidemiol. 2007;36(5):991–1000. pmid:17591639
  106. 106. Fezaa O, M'ghirbi Y, Savellini GG, Ammari L, Hogga N, Triki H, et al. Serological and molecular detection of Toscana and other Phleboviruses in patients and sandflies in Tunisia. BMC Infect Dis. 2014;14:598. pmid:25398483
  107. 107. Amro A, Gashout A, Al-Dwibe H, Zahangir Alam M, Annajar B, Hamarsheh O, et al. First molecular epidemiological study of cutaneous leishmaniasis in Libya. PLoS Negl Trop Dis. 2012;6(6):e1700. pmid:22724036
  108. 108. Feinsod FM, Ksiazek TG, Scott RM, Soliman AK, Farrag IH, Ennis WH, et al. Sand fly fever-Naples infection in Egypt. Am J Trop Med Hyg. 1987;37(1):193–6. pmid:3037932
  109. 109. Hammami-Ghorbel H, Ben Abda I, Badri T, Chelbi H, Fenniche S, Mokhtar I, et al. Mucosal leishmaniasis of the lip: an emerging clinical form in Tunisia. J Eur Acad Dermatol Venereol. 2015;29(6):1212–5. pmid:24910266
  110. 110. Ben Salah AB, Ben Ismail R, Amri F, Chlif S, Ben Rzig F, Kharrat H, et al. Investigation of the spread of human visceral leishmaniasis in central Tunisia. Trans R Soc Trop Med Hyg. 2000;94(4):382–6. pmid:11127239
  111. 111. Gramiccia M, Gradoni L. The current status of zoonotic leishmaniases and approaches to disease control. Int J Parasitol. 2005;35(11–12):1169–80. pmid:16162348
  112. 112. Du R, Hotez PJ, Al-Salem WS, Acosta-Serrano A. Old World Cutaneous Leishmaniasis and Refugee Crises in the Middle East and North Africa. PLoS Negl Trop Dis. 2016;10(5):e0004545. pmid:27227772
  113. 113. Medlock JM, Hansford KM, Van Bortel W, Zeller H, Alten B. A summary of the evidence for the change in European distribution of phlebotomine sand flies (Diptera: Psychodidae) of public health importance. J Vector Ecol. 2014;39(1):72–7. pmid:24820558
  114. 114. Alten B, Maia C, Afonso MO, Campino L, Jiménez M, González E, et al. Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum. PLoS Negl Trop Dis. 2016;10(2):e0004458. pmid:26900688
  115. 115. Poeppl W, Obwaller AG, Weiler M, Burgmann H, Mooseder G, Lorentz S, et al. Emergence of sandflies (Phlebotominae) in Austria, a Central European country. Parasitol Res. 2013;112(12):4231–7. pmid:24126902
  116. 116. Fischer D, Moeller P, Thomas SM, Naucke TJ, Beierkuhnlein C. Combining climatic projections and dispersal ability: a method for estimating the responses of sandfly vector species to climate change. PLoS Negl Trop Dis. 2011;5(11):e1407. pmid:22140590
  117. 117. Dvorak V, Hlavackova K, Kocisova A, Volf P. First record of Phlebotomus (Transphlebotomus) mascittii in Slovakia. Parasite. 2016;23:48. pmid:27849514
  118. 118. Bounoua L, Kahime K, Houti L, Blakey T, Ebi KL, Zhang P, et al. Linking climate to incidence of zoonotic cutaneous leishmaniasis (L. major) in pre-Saharan North Africa. Int J Environ Res Public Health. 2013;10(8):3172–91. pmid:23912199
  119. 119. Gradoni L. Epidemiological surveillance of leishmaniasis in the European Union: operational and research challenges. Euro Surveill. 2013;18(30):20539. pmid:23929176