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Tick species characterization and molecular studies were performed within ornithological surveys conducted during 2010 and 2011 in the Lazio Region of central Italy. A total of 137 ticks were collected from 41 migratory birds belonging to 17 species (four partial migrants and 13 long-distance migrants). Most ticks were nymphs, with a predominance of Hyalomma marginatum marginatum and H. m. rufipes, and a small portion of Ixodes and Amblyomma species. All tick species analyzed were infected, and the molecular pathogen recognition revealed the presence of Rickettsia aeschlimannii, Rickettsia africae, Erlichia spp., Coxiella burnetii, Borrelia burgdorferi sensu lato group, and Babesia microti, whereas no genomic DNA of Bartonella spp. or Francisella tularensis was detected. The results of the survey show that H. marginatum ticks appear to be a vector of microbial agents that may affect human and animal health and that migratory birds may be an important carrier of these ticks. Additional studies are needed to better investigate the role of migratory birds in the epidemiology of these pathogens.

In Italy, West Nile virus (WNV) equine outbreaks have occurred annually since 2008. Characterizing WNV vector habitat requirements allows for the identification of areas at risk of viral amplification and transmission. Maxent-based ecological niche models were developed using literature records of 13 potential WNV Italian vector mosquito species to predict their habitat suitability range and to investigate possible geographical associations with WNV equine outbreak occurrence in Italy from 2008 to 2010. The contribution of different environmental variables to the niche models was also assessed. Suitable habitats for Culex pipiens, Aedes albopictus, and Anopheles maculipennis were widely distributed; Culex modestus, Ochlerotatus geniculatus, Ochlerotatus caspius, Coquillettidia richiardii, Aedes vexans, and Anopheles plumbeus were concentrated in north-central Italy; Aedes cinereus, Culex theileri, Ochlerotatus dorsalis, and Culiseta longiareolata were restricted to coastal/southern areas. Elevation, temperature, and precipitation variables showed the highest predictive power. Host population and landscape variables provided minor contributions. WNV equine outbreaks had a significantly higher probability to occur in habitats suitable for Cx. modestus and Cx. pipiens, providing circumstantial evidence that the potential distribution of these two species coincides geographically with the observed distribution of the disease in equines.

The first record of Ornithodoros (Alectorobius) coniceps (Canestrini) was reported for Italy in 1877, inside the interstices of the ancient mosaics at S. Marco Basilica in Venice. Afterwards only few discoveries of the species are reported for Italy; the last record is dated back to 1984, in L'Aquila town (Abruzzo Region). The present study shows the data of a survey carried out as a result of a massive infestation by O. coniceps in an ancient villa in Anzio town (Latium region) recently restored. In the past decades the villa has been fallen into disrepair, becoming an occasional shelter for wild animals mainly pigeons, that colonized the whole building for generations. This case appears worthy of note because it is the first record of this species after more than 25 years in Italy. A total of 136 specimens were collected by three methods: manual, mechanical aspirators and Wilson traps. Wilson trapping indicates positive O. coniceps tropism for CO(2).

A survey was carried out on phlebotomine sand flies and their feeding habits at a hypoendemic focus of Leishmania infantum in Macerata province, central Italy. During two consecutive years (2000-2001), 1465 sand fly specimens (42.5% of which were males) were collected from a variety of diurnal resting sites in the municipality of Camerino. The most prevalent species was Phlebotomus perniciosus (76.6%), followed by P. papatasi (10.4%), Sergentomyia minuta (9.1%), Phlebotomus perfiliewi (3.3%) and P. mascittii (0.5%). Among the 842 females collected, 578 (68.6%) were blood-fed. Based on the results of blood meal analyses, P. perniciosus fed on man, dogs, equines, sheep and birds; P. perfiliewi on dogs, equines, sheep and birds; P. papatasi on dogs, equines and birds. Two specimens of P. mascittii fed on equines. Forage ratios (FRs) and host selectivity indices gave different results for the large domestic animals. More than 95% of the specimens collected inside a stable, dog kennel, sheep pen and chicken house were found to have fed on the animals housed in the respective shelters. In addition, at one collecting site where almost all the hosts mentioned above were present simultaneously, both P. perniciosus and P. perfiliewi were found to have fed on all five species, indicating that host choice was probably related to its availability (i.e. number and size) rather than specific attractiveness. The feeding habits of the two Leishmania vectors may have implications for the epidemiology of leishmaniasis in urban and peri-urban areas, where sand fly females deprived of other vertebrate hosts (particularly the larger species) may begin to bite humans and dogs more frequently.

During the sand fly season of 2001, sand flies were collected in two different regions of Italy to investigate the northern distribution of Phlebotomus neglectus. The study areas were two provinces of northern Italy, Ivrea and Verona, in Piedmont and Veneto regions respectively. Sticky traps and CDC miniature light traps were used both inside and outside domestic and peri-domestic environments. Sand flies were also collected in domestic resting sites with mouth and electric aspirators. Of 1,295 sand fly specimens collected, 855 were from the Veneto region and 440 were from the Piedmont region. Five species of the genera Phlebotomus and Sergentomyia were identified. S. minuta (66.3%) was the most abundant sand fly followed by P. perniciosus (22.2%), P. neglectus (10.3%) and P. papatasi (1.2%). Only one specimen of P. mascittii was caught in Piedmont region. P. neglectus was found in 9 out of 15 (60%) of the sites where sand flies were found with a prevalence of 1.5% to 45.8%; the highest value was recorded in Piedmont region. P. neglectus was mostly associated with peridomestic and domestic sites. The results confirm previous observations on the presence of P. neglectus in northern Italy and suggest that this species is probably widespread in the area. From a review of all previous published and unpublished records of P. neglectus, it appears that this species is present in only two areas of the country, namely in the regions of Friuli Venezia Giulia, Veneto and Piedmont in northern Italy and the regions of Calabria, Apulia and Sicily in southern Italy. The apparent absence of P. neglectus in Central Italy is discussed and the resulting settlement through two probable migration routes from the East is analysed.

A study was undertaken to establish the susceptibility of two recently colonized sand fly species, Phlebotomus perniciosus and P. papatasi to some insecticides. A laboratory colony of P. papatasi, unexposed to insecticides for a period of ten years, was used as reference strain. Bioassay tests were carried out according to the WHO standard protocols based on the mortality rates recorded at different exposure times. Serial (from 1 to 60 min) exposures to DDT 2%, lambda-cyhalothrin 0.06% and permethrin 0.2% were tested on groups of 30 adult sugar-fed female sand flies, for a total of 7,470 specimens. Data were subjected to probit analysis and the susceptibility was calculated at LT50 and LT95 by comparison with the laboratory reference strain. The LT50 values for P. perniciosus were 19.9, 3.2 and 6.9 min, and for P. papatasi 18.0, 7.4 and 11.0 min, using DDT, lambda-cyhalothrin and permethrin, respectively. The results showed that two Italian populations of P. perniciosus and P. papatasi from Campania region and from Rome, respectively, are susceptible to the insecticides tested as compared with the reference strain used.

The dog tick, Rhipicephalus sanguineus Latreille, 1806 (Acari: Ixodidae), is a public health problem since it is widely distributed in Italy and because of its role in the transmission of many pathogens to man and dog which is its preferred host. This review deals with the main aspects of the biology and ecology of Rh. sanguineus habitat, developmental time, distribution and seasonality, behaviour and vector competence. Moreover, the preminent role of Rh, sanguineus in the transmission of boutonneuse fever is discussed.

An entomological survey was carried out on leishmaniasis vectors (Diptera: Psychodidae) in North Italy (Verona province). A total of 382 sandfly specimens was caught by sticky traps in 6 collecting stations. The species identified were: Phlebotomus perniciosus (62.3%), P. neglectus (= major s.l.) (5.2%), P. papatasi (2.1%), P. mascittii (0.3%) and Sergentomyia minuta (30.1%). After the description of the olotype of P. neglectus by Tonnoir (1921) in Trieste (Opicina), this is the first time that the species is recorded in a region of North Italy being previously collected only in the regions of Southern such as Apulia, Calabria, Sicily. The role of the sandfly species in the transmission of leishmaniasis in the focus is also discussed.

Lyme disease is caused by three borrelial species, B. burgdorferi sensu stricto, B. garinii and Borrelia group VS461. In a restricted biotope of the Bolzano province, in the Caldaro community, five clones of two borrelial variants were isolated from Ixodes ricinus ticks. A preliminary serological study showed that the two variants cross-reacted with B. burgdorferi B31 and B. garinii N34 strains, respectively. The isolates were genomically related with strains B31 and N34, respectively, sharing a similar plasmid and restriction fragment length polymorphism profile with these strains. The phenotypic pattern of the Caldaro isolates-namely their protein and antigenic profile-showed infra-subspecific variation compared to related strains B31 and N34 respectively. The observed phenotypic variability between strains isolated from the same biotope and in the same tick host strongly indicated the variability of gene-encoded characters is a constant characteristic of borrelial strains, even when from the same ecological niche.

The paper analyzes published and unpublished data of sandfly collections carried out in Italy by one of the authors (M.M.) over a period of 18 years (1975-1993). These data are discussed in relation to the collection methods and the habitats. The leishmaniasis foci surveyed are localized in 11 regions of Central and Southern Italy and in the two main islands, Sicily and Sardinia. Five collection methods were used: i) sticky traps, ii) light traps, iii) window exit traps, iv) emergence traps, and v) hand catches. Captures were performed in domestic and sylvatic habitats in rural, urban and periurban areas. A total of 81,915 sandflies has been collected. Specimens were identified as belonging to 6 species: Phlebotomus perniciosus (46.1%), P. perfiliewi (43.8%), P. major (0.2%), P. mascittii (0.1%), P. papatasi (0.3%), and Sergentomyia minuta (9.5%). P. perniciosus, P. perfiliewi and S. minuta have been reported in almost all the regions samples, P. major only in 3 regions of South Italy (Apulia, Calabria and Sicily), P. mascitti in 4 regions of Central Italy (Tuscany, Latium, Abruzzo, Molise) and in Campania, P. papatasi in 6 regions without any definite geographical distribution. From the analysis of sticky trap captures P. perniciosus seems to be the prevalent species in the domestic habitat (65.6%) even if present in the sylvatic one (21.8%). The report of P. perniciosus in both situations might indicate the ability of the species to colonize a large range of habitats. P. perfiliewi resulted as the predominant species (88.1%) in the domestic area from collections with CDC light traps. S. minuta was the most abundant species in the sylvatic conditions (76.6%) while P. papatasi showed a clear endophilic behaviour reaching high percentages only in bedrooms and stables. Moreover, taxonomic characters of spermathecae utilized in species identification are reported.

Temporal distribution of tick species was studied in the woodland "Macchia Grande" of Manziana in the province of Rome, Italy. A total of 2,494 ticks was collected by means of drag sampling during one year of survey (1993). Among the species identified, Ixodes ricinus (Linnaeus, 1758) (95.9%) was the most abundant, followed by Haemaphysalis inermis (Birula, 1895) (2.2%), Rhipicephalus bursa (Canestrini e Fanzago, 1877) (1.8%), Dermacentor marginatus Sulzer, 1776) (0.1%). I. ricinus was present during the whole year, showing a diphasic trend, with peaks in January-April (95-173 specimens per drag) and in November-December (29-126); H. inermis was recovered only during the cold season (January-April and in December) with the highest density in February (7); Rh. bursa was collected from May to October showing maximum occurrence in July (10). The presence of I. ricinus and H. inermis, proven vectors of Borrelia burgdorferi (Lyme disease) and TBE virus, is discussed in relation to the possible exposure risk for park visitors and operators.

The following 13 species of ticks, belonging to Ixodidae family, were recorded in Italy on horse (Equus caballus) since 1931: Ixodes ricinus, I. gibbosus, Haemaphysalis inermis, H. parva, H. punctata, H. sulcata, Dermacentor marginatus, Rhipicephalus sanguineus, Rh. bursa, Rh. turanicus, Hyalomma marginatum, Hy. detritum, Boophilus annulatus. The regional distribution and the role of the species in the transmission of pathogens are reported.

Haemaphysalis (Alloceraea) inermis Birula specimens have been collected in a woody land of Manziana in the province of Rome. This is the first report in Latium region and suggests the presence of autochthonous populations of the species in Central Italy since no exotic fauna has been introduced in the past in the area studied. The role of H. inermis on the transmission of pathogens for humans and animals is discussed.

A survey on phlebotomine sandflies (Diptera, Psychodidae) was carried out in the province of L'Aquila, Abruzzo region (Italy). Ten collecting sites at altitudes between 700 and 1,070 m a.s.l., produced a total of 324 specimens (81.1% males), 72.86% being Phlebotomus perniciosus, 3.08% P. mascittii, 0.30% P. papatasi and 23.76% Sergentomyia minuta. The collecting sites at 1,070, 950 and 775 m a.s.l. are the highest levels recorded in Italy for P. perniciosus, P. mascittii and P. papatasi, respectively. P. perfiliewi, the proven vector of cutaneous leishmaniasis (CL) in the Abruzzo region (Maroli et al., 1987) was absent. The probable role of P. perniciosus in the transmission of the sporadic CL cases reported from the area is discussed.

In the urban periphery of Rome, two sub-zones could be distinguished, characterized by uncultivated steppeland and by small shacks with large quantities of domestic refuse, respectively. Rhipicephalus sanguineus appeared to be typical of this second sub-zone. R. sanguineus adults and nymphae were captured in different seasonal periods and were checked for the prevalence of rickettsiae of the Spotted Fever (SF) group. Moreover, larvae from hatched eggs, laid by captured R. sanguineus females, were checked for the transovarial transmission of rickettsiae. Ten lots each of three guinea-pigs, seronegative to rickettsiae of the SF group, were inoculated with R. sanguineus extracts, prepared from adults or larvae. Clinical signs of infection, fever and scrotal reaction, could be observed only in one lot of guinea-pigs inoculated with adult parasites. On the other hand, in 8 out of 10 guinea pig lots, antibodies to the soluble antigens of R. conori and R. slovaca were observed by the complement fixation (CF) test. In the remaining two lots only antibodies to R. slovaca were detected. No antibodies to Coxiella burneti could be demonstrated in the same sera.