Giardia duodenalis sub-Assemblage of animal and human origin in horses

In order to evaluate infection occurrence and the potential zoonotic role of horse isolates of Giardia duodenalis, 431 individual fecal samples were genetically characterized by PCR tests -coupled sequencing and phylogenetic analysis. Thirty-seven (8.6%) animals resulted infected by different Assemblage. The presence of sub-Assemblage was assessed by characterizing the β-giardin gene for 16 of the 37 positive horses. Ten isolates showed 99.6% to 100% homology with the sub-Assemblage described as B1-2 and B1-6, three Assemblage A showed 99.8% homology with sub-Assemblage A1, while one Assemblage E displayed 98.8% homology with sub-Assemblage E3. Furthermore, one isolate characterized as Assemblage A showed 99.6% homology with the sub-Assemblage B1-2 and one characterized as E was 100% identical with sub-Assemblage B1-6. These results demonstrate the presence of both animal and human sub-Assemblage of G. duodenalis in horses from Italy. Epidemiological and sanitary implications are discussed.

A gallery of the key characters to ease identification of Dermanyssus gallinae (Acari: Gamasida: Dermanyssidae) and allow differentiation from Ornithonyssus sylviarum (Acari: Gamasida: Macronyssidae)

Background

Dermanyssus gallinae (poultry red mite) is a major threat for the poultry industry and is of significant interest for public health. Identification of D. gallinae can be difficult for scientists not familiar with mite morphology and terminology especially when trying to use identification keys. Moreover, this species may easily be confused with another dermanyssoid mite, Ornithonyssus sylviarum (northern fowl mite), which often shares the same hosts and environment.

Methods

Specimens of D. gallinae were collected at poultry farms in the Puglia and performed for light and scanning electron microscopy observations, identification and micrographs. Moreover specimens of O. sylviarum were collected separately macerated and mounted on slides for light microscopy observations, identification and pictures.

Results

The micrographs used in this study, based on LM and SEM observations, highlight the following important identifying characters of D. gallinae: the prominent shoulders of the dorsal shield and the jagged edges of the shield reticulations, the position of setae j1, s1 and the epigynal pores, and the presence on tibia IV pl of one seta. Additional micrographs highlighting the shape of the dorsal (abruptly narrowed posteriorly) and epigynal (narrowly rounded posteriorly) shields and the chelicera (elongate, with distinct digits) of O. sylviarum enable its differentiation from D.gallinae.

Conclusion

The photographic support provided here (both LM and SEM pictures) can be considered a practical tool for scientists who are not well acquainted with the morphology of D.gallinae, and who are involved with classical and molecular systematics, veterinary and human health aspects of poultry red mites.

Endoparasite infections in pet and zoo birds in Italy

Faecal samples were individually collected from pet (n = 63) and zoo (n = 83) birds representing 14 orders and 63 species. All the samples were examined by faecal flotation technique. In a subgroup of samples (n = 75), molecular assays were also used to detect Cryptosporidium oocysts and Giardia duodenalis cysts. Overall, 35.6% of the birds harboured parasites (42.2% of zoo birds and 27% of pet birds), including Strongyles-Capillarids (8.9%), Ascaridia (6.8%), Strongyles (5.5%), G. duodenalis Assemblage A (5.3%), Coccidia (4.1%), Cryptosporidium (4%), Porrocaecum (2.7%), Porrocaecum-Capillarids (2%), and Syngamus-Capillarids (0.7%). The zoonotic G. duodenalis Assemblage A and Cryptosporidium were exclusively found in Psittaciformes, with prevalences of 10.3% and 7.7% within this bird group. Zoo birds were more likely to harbor mixed infections (OR = 14.81) and symptomatic birds to be parasitized (OR = 4.72). Clinicians should be aware of the public health implications posed by zoonotic G. duodenalis Assemblages and Cryptosporidium species in captive birds.

Acaricide residues in laying hens naturally infested by red mite Dermanyssus gallinae

In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides - sometimes in high concentrations - to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS.

Ninety-one (40.4%) samples were positive to carbaryl and four samples (1.7%) were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm) were registered in the skin and fat of birds from two farms (p<0.01), although these concentrations remained below the maximum residue limit (MRLs) (0.05 ppm) (p<0.01). All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm) (p<0.01) of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2%) were found to be contaminated by carbaryl, and 4 (8.8%) by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl) or not licensed for use (permethrin) in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle.

Giardia duodenalis genotypes and Cryptosporidium species in humans and domestic animals in Côte d'Ivoire: occurrence and evidence for environmental contamination

Giardia duodenalis genotypes and Cryptosporidium species were studied in humans and free-ranging animals living in closed enclaves in Côte d'Ivoire. Three hundred and seven stool samples were tested from humans, and 47 from freely roaming domestic animals (dogs, goats, ducks, chickens). Molecular characterization of the isolates was performed by sequence analysis of a portion of the SSU-rDNA for Giardia and the COWP gene for Cryptosporidium, and a β-giardin SYBR-green real-time PCR was also used to confirm the assignment of Giardia isolates to Assemblages. In humans, genotyping of Giardia assigned many of the sequences (43/56 by the SSU-rDNA gene, and 36/61 by the β-giardin gene) to Assemblage B. The animal species harboured only zoonotic Assemblages A and B, except for dogs, in which host specific Assemblages C and D were also detected. Cryptosporidium meleagridis, C. parvum and C. hominis were detected in humans, while among the animals only chickens were found positive for oocysts, identified as C. meleagridis and C. parvum. The results provide further evidence about the role of free-ranging domestic animals living closely with humans in the environmental dissemination and potential transmission of these anthropozoonotic pathogens to humans.

Genotyping of Giardia duodenalis among children and dogs in a closed socially deprived community from Italy

Molecular characterization of Giardia duodenalis cysts from humans and animals living in well-defined contexts is useful to study the circulation of isolates and represents a tool to evaluate zoonotic infection risk. The presence of giardiasis in children living in a disadvantaged and socially deprived small Rom community, as well in dogs roaming freely in the same context was carried out by microscopic analysis and beta-giardin gene amplification. Five out of 14 children were found positive at microscopic examination for G. duodenalis and six positive at PCR, while eight out of 14 dogs tested both microscopically and molecularly positive for G. duodenalis. Moreover, most of the children and dogs were symptomatic. Molecular characterization of Giardia positive samples from children and dogs showed 99.5% identity with Giardia Assemblage A1. The dog-specific genotypes C and D were not found. The findings of this survey provide the first European evidence to support the possible role of dogs in zoonotic transmission involving children and stray dogs in a closed context with very low standards of hygiene (i.e. Rom community), and these results show the need to monitor the health of marginal populations to safeguard ethnic minority groups.

Traumatic myiasis by Wohlfahrtia magnifica in Italy

Seven farms, two in Central Italy and five in Southern Italy, were visited for the presence of larvae-infested wounds. Ninety-six (3%) out of 3129 sheep examined had a traumatic myiasis with a very high percentage of infested animals found only in a farm (10.5%). Wounds were mainly localized on the vulva and prepuce. Infested animals were restless, anxious, and reluctant to graze. None of the 10 goats in one infested flock had wounds, whereas a shepherd dog from another flock presented a wound on the ear. All the larvae and adults reared from them in the laboratory were identified as Wohlfahrtia magnifica (Schiner, 1862) (Diptera, Sarcophagidae). The cases presented here are the first clinical cases of wohlfahrtiosis in sheep and dogs reported in Italy, and indicate that this myiasis is endemic in this country. A wider epidemiological investigation on the prevalence, incidence and seasonality of W. magnifica infestation of Italian W. magnifica population/s would be useful to understand its geographical provenience and the likely risk for its spreading throughout Italy and other non-endemic areas.

Investigation of Toxoplasma gondii presence in farmed shellfish by nested-PCR and real-time PCR fluorescent amplicon generation assay (FLAG)

To evaluate the presence of Toxoplasma gondii in edible farmed shellfish, 1734 shellfish specimens i.e., 109 Crassostrea gigas (6 pools), 660 Mytilus galloprovincialis (22 pools), 804 Tapes decussatus (28 pools) and 161 Tapes philippinarum (6 pools), were collected from the Varano Lagoon (Apulia, Italy). Shellfish from 62 pools were subjected to two molecular techniques: a nested-PCR assay, and a fluorescent amplicon generation (FLAG) real-time PCR assay, both based on the multi-copy B1 target, were performed. One pooled sample of gills from C. gigas and one pooled sample of haemolymphs from T. decussatus were assessed as positive for T. gondii DNA by both techniques. The results demonstrated the presence of T. gondii in edible farmed C. gigas and T. decussatus and indicate that there may be a considerable health threat involved in eating contaminated raw shellfish.

Evaluation of the house fly Musca domestica as a mechanical vector for an anthrax

Anthrax is a disease of human beings and animals caused by the encapsulated, spore-forming, Bacillus anthracis. The potential role of insects in the spread of B. anthracis to humans and domestic animals during an anthrax outbreak has been confirmed by many studies. Among insect vectors, the house fly Musca domestica is considered a potential agent for disease transmission. In this study, laboratory-bred specimens of Musca domestica were infected by feeding on anthrax-infected rabbit carcass or anthrax contaminated blood, and the presence of anthrax spores in their spots (faeces and vomitus) was microbiologically monitored. It was also evaluated if the anthrax spores were able to germinate and replicate in the gut content of insects. These results confirmed the role of insects in spreading anthrax infection. This role, although not major, given the huge size of fly populations often associated with anthrax epidemics in domestic animals, cannot be neglected from an epidemiological point of view and suggest that fly control should be considered as part of anthrax control programs.

[Prevalence of Plasmodium spp. in asymptomatic African immigrants assessed by nucleic acid sequence based amplification]

Malaria is one of the most important infectious diseases in the world. Although most cases occur in the tropical regions of Africa, Asia, Central and South America, there is in Europe a significant increase in the number of imported cases in non-endemic countries, in particular due to the higher mobility in today's society. The prevalence of a possible asymptomatic infection with Plasmodium species was assessed using Nucleic Acid Sequence Based Amplification (NASBA) assays on clinical samples collected from 195 study cases with no clinical signs related to malaria and coming from sub-Saharan Africa. In addition, base-line demographic, clinical and socio-economic information was collected from study participants who also underwent a full clinical examination. Sixty-two study subjects (31.8%) were found positive for Plasmodium using a pan Plasmodium specific NASBA based on the small subunit 18S rRNA gene (18S NASBA). Twenty-four samples (38%) of the 62 positive study cases were found positive with a Pfs25 mRNA NASBA, which specifically detects gametocytes of Plasmodium falciparum. This study showed that a substantial proportion of people originating from malaria endemic countries harbour malaria parasites in their blood. If transmission conditions are available, they could be a reservoir.

Phylogenetic relationship between Dermanyssus gallinae populations in European countries based on mitochondrial COI gene sequences

Phylogenetic analysis of Dermanyssus gallinae mites originating from UK, France and Italy was performed using partial amplification of the mitochondrial COI gene. Results showed that UK samples reveal the greatest variation and diversity and are linked to one of the French populations highlighting North-South genetic transitions in European red mite populations. Intra-farm variations between mite samples highlighted the diversity between national populations and possibly its origin from the different chemical strategies used in each country.

Evaluation of the poultry red mite, Dermanyssus gallinae (Acari: Dermanyssidae) susceptibility to some acaricides in field populations from Italy

Red mite field populations from seven naturally infested Italian caged laying poultry farms were investigated for their susceptibility to acaricide formulations available on the market, containing amitraz, carbaryl and permethrin. A minimum of 3,000 mites of all stages were collected from each farm and were tested with five acaricide concentrations (5, 10, 20, 50, 100%) plus an untreated control (0%). Field red mite populations were found to be tolerant even with the highest concentrations with carbaryl and permethrin for six (86%) and three (42%) of the investigated farms, respectively (P < 0.05). Furthermore, six (86%) of the investigated farms showed a red mite population susceptible to amitraz at any concentration. Out of the seven field populations tested with amitraz, one population is becoming less tolerant whereas another was the most tolerant to carbaryl and permethrin at any concentration. Data show that the lack of effectiveness of some acaricides is spreading in Europe and call for the adoption of alternative management strategies to avoid development of resistance.

Immunoenzymatic analysis and genetic detection of Cryptosporidium parvum in lambs from Italy

Cryptosporidiosis is a worldwide-diffused protozoan disease causing important economic losses to animal husbandry and livestock production. Additionally, several species/genotypes of Cryptosporidium have a relevant zoonotic potential and ruminants may be important sources of infection for human beings. Nonetheless, in Europe, little is known of the presence of Cryptosporidium in sheep nor on the species/genotypes involved. To obtain information on the occurrence of cryptosporidiosis in lambs and the potential zoonotic role of the Cryptosporidium isolates, one hundred and forty-nine faecal samples individually collected from lambs in central Italy have been examined for the presence of Cryptosporidium. All faecal specimens were processed with a commercial ELISA kit immunoassay and all ELISA-positive samples were further analyzed genetically. Twenty-six ELISA-positive samples scored positive at the PCR and the sequences obtained displayed 100% identity with the zoonotic Cryptosporidum parvum. This work suggests for the first time that lambs in Italy may shed C. parvum, thus representing a potential public health hazard.

Screening of the topical anti-inflammatory activity of the bark of Acacia cornigera Willdenow, Byrsonima crassifolia Kunth, Sweetia panamensis Yakovlev and the leaves of Sphagneticola trilobata Hitchcock

ETHNOPHARMACOLOGICAL RELEVANCE

An investigation of topical anti-inflammatory activity was undertaken on plants used in Central America traditional medicine.

AIM OF STUDY

Four herbal drugs used in the folk medicine of Central America to treat inflammatory skin affections (Acacia cornigera bark, Byrsonima crassifolia bark, Sphagneticola trilobata leaves and Sweetia panamensis bark) were evaluated for their topical anti-inflammatory activity.

MATERIALS AND METHODS

Petroleum ether, chloroform and methanol extracts were obtained for herbal medicines and then extracts were tested on Croton oil-induced ear dermatitis model in mice.

RESULTS

Almost all the extracts reduced the Croton oil-induced ear dermatitis in mice and the chloroform ones showed the highest activity, with ID(50) (dose giving 50% oedema inhibition) values ranging from 112 microg/cm(2) (Byrsonima crassifolia) to 183 microg/cm(2) (Sphagneticola trilobata). As reference, ID(50) of the non-steroidal anti-inflammatory drug indomethacin was 93 microg/cm(2).

CONCLUSIONS

Lipophilic extracts from these species can be regarded as potential sources of anti-inflammatory principles.

Development of specific oligonucleotide probes to detect Vibrio species

Many species of Vibrio are responsible for diseases in marine organisms and for economic losses to the aquaculture industry. The aim of this preliminary study was to obtain species-specific DNA zones to be used as potential probes from a phylogenetic analysis of the 23S ribosomal RNA (rRNA) gene of different Vibrio species from marine and human organisms. Species-specific probes were identified for V. parahaemolyticus, V. fortis, V. splendidus, and for two clusters of taxonomically related species, namely V. harveyi/campbelli and V. lentus/aestuarianus. A reverse line blot assay showed that the designed probes can specifically detect the different Vibrio species, thereby proving that these probes can be used to evaluate the presence of pathogenic and nonpathogenic Vibrio species in the sea and in marine organisms to assist in the investigation of environmental risks.

Epidemiological scenario of giardiosis in dogs from central Italy

In order to update and implement the data on the epidemiological situation of giardiosis in the Italian arena, stool samples from 240 dogs living in the Abruzzo region (central Italy) were examined for prevalence, risk factors, and genotypes. Giardia duodenalis cysts were detected in 26.6% of the dogs and kennel dogs tested. Dogs younger than 12 months (38%) and with diarrhea (46%) were statistically more affected. Species-specific G. duodenalis assemblages (C and D) were identified in kennel and in privately owned dogs, while the zoonotic assemblage A was identified in privately owned dogs. In light of these results, giardiosis in dogs, and mainly in well-cared dogs, is still a problem of concern and may pose a public health risk.

Prevalence of Plasmodium spp. in malaria asymptomatic African migrants assessed by nucleic acid sequence based amplification

Background

Malaria is one of the most important infectious diseases in the world. Although most cases are found distributed in the tropical regions of Africa, Asia, Central and South Americas, there is in Europe a significant increase in the number of imported cases in non-endemic countries, in particular due to the higher mobility in today's society.

Methods

The prevalence of a possible asymptomatic infection with Plasmodium species was assessed using Nucleic Acid Sequence Based Amplification (NASBA) assays on clinical samples collected from 195 study cases with no clinical signs related to malaria and coming from sub-Saharan African regions to Southern Italy. In addition, base-line demographic, clinical and socio-economic information was collected from study participants who also underwent a full clinical examination.

Results

Sixty-two study subjects (31.8%) were found positive for Plasmodium using a pan Plasmodium specific NASBA which can detect all four Plasmodium species causing human disease, based on the small subunit 18S rRNA gene (18S NASBA). Twenty-four samples (38%) of the 62 18S NASBA positive study cases were found positive with a Pfs25 mRNA NASBA, which is specific for the detection of gametocytes of Plasmodium falciparum. A statistically significant association was observed between 18S NASBA positivity and splenomegaly, hepatomegaly and leukopaenia and country of origin.

Conclusion

This study showed that a substantial proportion of people originating from malaria endemic countries harbor malaria parasites in their blood. If transmission conditions are available, they could potentially be a reservoir. Thefore, health authorities should pay special attention to the health of this potential risk group and aim to improve their health conditions.

Phylogenetic relationships of Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) within the order Spirurida inferred using mitochondrial cytochrome c oxidase subunit 1 (cox1) gene analysis

The present study investigated genetic variability within a population of Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) affecting horses in an endemic area of central Italy using polymerase chain reaction (PCR)-coupled sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). No different cox1 sequences were detected in any of the H. muscae individual, while two haplotypes representing H. microstoma individuals differed for one substitution. The pairwise distance between the H. muscae and H. microstoma was 11%, coding for five amino acid changes. The sequence of an informative region within the cox1 gene of H. microstoma and H. muscae was analyzed by Maximum Likelihood and Bayesian phylogenetic methods using available mitochondrial sequences spirurid taxa belonging to Filarioidea, Thelazioidea, and Habronematoidea. Phylogenetic analysis supported the split of the tree into two sister spirurid groups, Habronematoidea and Filarioidea + Thelazioidea. The phylogenetic and evolutionary implications of Habronema with Filaroidea and Thelazioidea are discussed.

Species-specific identification of equine cyathostomes resistant to fenbendazole and susceptible to oxibendazole and moxidectin by macroarray probing

Cyathostome populations in horses on two farms located in central Italy with a history of fenbendazole (FBZ) resistance were investigated with the Faecal Egg Count Reduction Test to evaluate the susceptibility to oxibendazole and moxidectin. Faecal eggs were collected pre- and post-treatment on each farm and molecularly examined with a Reverse Line Blot (RLB) assay able to unequivocally detect and identify 13 cyathostome species. Resistance to FBZ was confirmed on both farms, while oxibendazole and moxidectin demonstrated 97% and 100% efficacy, respectively. Overall eight species of cyathostomes (Coronocyclus labiatus, Cylicocyclus ashworthi, Cylicocyclus nassatus, Cyathostomum catinatum, Cylicostephanus longibursatus, Cylicostephanus goldi, Cylicostephanus calicatus and Cylicocyclus insigne) were identified in pre-treatment samples. Coronocyclus labiatus and C. goldi were identified after treatment with FBZ while C. calicatus and C. labiatus were shown to be <100% susceptible to oxibendazole. These data confirm that resistance to benzimidazoles is established in cyathostome populations from horse farms in Italy and that they are susceptible to moxidectin. The oxibendazole has been successfully demonstrated for the first time as effective against Italian populations of cyathostomes resistant to other benzimidazoles. The RLB assay herein used showed to be useful to study the distribution of these parasitic populations at species level under field conditions and could represent a powerful tool in broader investigation of drug resistance in horse farms from several countries.

Identification of the intermediate hosts of Habronema microstoma and Habronema muscae under field conditions

A polymerase chain reaction (PCR)-based assay was used for the specific detection of Habronema microstoma and Habronema muscae (Nematoda, Spirurida) in order to identify the intermediate hosts of both nematode species under field conditions. A total of 1087 netted and 165 laboratory-bred flies were tested. Flies were identified as Musca domestica Linnaeus 1758, Musca autumnalis De Geer 1776, Haematobia irritans (Linnaeus 1758), Haematobia titillans (De Geer 1907) and Stomoxys calcitrans (Linnaeus 1758) (Muscidae). Genomic DNA was extracted from pools of fly heads, thoraces and abdomens, and 703 samples were subjected to a duplex two-step semi-nested PCR assay to specifically detect diagnostic regions within the ribosomal ITS2 sequence of both H. microstoma and H. muscae. Stomoxys calcitrans specimens were positive for H. microstoma DNA and M. domestica specimens were positive for H. muscae DNA. In particular, PCR-positive samples derived from both farm-netted and laboratory-bred flies. The present study represents the first evidence of the vectorial competence of different fly species as intermediate hosts of Habronema stomachworms under field conditions. We discuss the roles of S. calcitrans and M. domestica in transmitting H. microstoma and H. muscae.

Dermatophytoses in cats and humans in central Italy: epidemiological aspects

Two hundred hair/skin samples were collected from 2002 to 2004 from two groups of cats (privately owned and stray cats from a shelter) and 165 samples were obtained during the same period from persons in whom dermatophyte infection was highly suspected. The epidemiological data were statistically evaluated. Thirteen of the 100 privately owned cats (13%) and 100% of the stray cats were positive; of the 165 human samples examined 109 (66%) were positive for dermatophytes. Microsporum canis was the most common dermatophyte isolated in both cat groups while Trichophyton mentagrophytes was the most common in humans. Interestingly, a geophylic dermatophyte species (Microsporum gypseum) was found to be present and associated with clinical signs. Living in the countryside proved to be a risk factor for dermatophytoses in privately owned cats while in humans the main risk factor for M. canis was contact with animals followed by young age. None of the variables considered was associated with positivity for T. mentagrophytes while positivity for other fungi was correlated with life in the countryside.

Occurrence of anthelmintic resistant equine cyathostome populations in central and southern Italy

In the present survey, 276 horses bred on 16 farms located in central and southern Italy were investigated for the presence of drug resistant cyathostomes by a Fecal Egg Count Reduction Test (FECRT). Sixteen to 20 animals were selected on each farm and randomly assigned to one of four equally sized treatment groups. Groups were treated with fenbendazole, pyrantel pamoate, ivermectin or moxidectin. Resistance to fenbendazole was declared on six farms (37.5%) and suspected in two farms (12.5%), with FECR values ranging from 41% to 88.3%. Resistance to pyrantel was found in two farms (12.5%) and was suspected in one case (6.2%), with FECR values ranging from 43% to 85.4%. Macrocyclic lactones remained effective on all farms. Only cyathostome third stage larvae (L3) were found in fecal cultures after treatment. This paper reports the first wide survey conducted in Italy for anthelmintic resistance in equine cyathostomes. The results indicate that multiple drug resistant equine cyathostomes are present in the central and southern regions of Italy. These data call for a geographically and numerically broader investigation of horse farms in all regions and for the development and implementation -among veterinarians, owners and managers of a plan to reduce the expansion of these anthelmintic resistant populations and control these important parasites.

Molecular diagnosis of equid summer sores

Equine cutaneous habronemosis, also known as "summer sores", is a parasitic infection caused by larvae of Habronema microstoma and Habronema muscae (Nematoda, Spirurida) released by dung-inhabiting fly vectors on abraded skin, skin wounds or muco-cutaneous transition sites. Larvae induce a local inflammatory reaction characterised by itching, granulomatous, ulcerated and, often non-healing, lesions. The diagnosis of summer sores may be unreliable mainly because of the limits of clinical and microscopic examination. The applicability of a semi-nested PCR assay developed for the diagnosis of gastric habronemosis has been herein demonstrated for the detection of the cutaneous infection. The potential applicability of this diagnostic tool may have for clinical and epidemiological studies of cutaneous habronemosis in equids is discussed.

Giardia and Cryptosporidium and public health: the epidemiological scenario from the Italian perspective

Giardia and Cryptosporidium spp. are protozoa that cause human and animal disease worldwide and often exhibit zoonotic transmission. This review gives ample information concerning the epidemiology of these parasites in Italy, i.e. prevalence data in humans, farm and pet animals, shellfish and aquatic environment. Moreover, it reports genotyping results obtained from different isolates, with particular emphasis on the spread of host-specific and zoonotic species/genotypes of various origin, and on molecular data that make the Italian situation different from that of other countries. Finally, possible explanations are given for the infrequent reports of Giardia and Cryptosporidium spp. outbreaks, despite widespread faecal contamination by these parasites.

Temporal occurrence of Cryptosporidium in the Manila clam Ruditapes philippinarum in northern Adriatic Italian lagoons

In order to evaluate the temporal occurrence of Cryptosporidium oocysts in Ruditapes philippinarum clams bred along the northeastern Italian Adriatic coast and molecularly characterize the isolates, 2,160 specimens (180 clams per month) were collected from three clam farms from January to December 2004. Two farms (sites A and B) were located in Venice (Chioggia, Veneto region) and one (site C) in the Marano Lagoons (Friuli Venezia Giulia region). Clams from 36 pools (i.e., one pool of 60 clams per month per site) were subjected to a high-sensitivity seminested PCR assay specific for a 360-bp diagnostic region internal to the Cryptosporidium spp. outer wall protein gene. Positive amplicons were sequenced and analyzed. Cryptosporidium DNA was found in clams from seven pools (sites A and B) during 1 month of sampling at site A and 6 months of sampling at site B, with Cryptosporidium hominis and Cryptosporidium parvum being detected. The expected infection rate of the clams was 0.36%. Site B showed a significantly higher expected infection rate (1.15%) than did the other sites (A = 0.14% and C = 0%). Given its high sensitivity and specificity, this seminested PCR assay can be considered a reliable tool for detecting and distinguishing species within the Cryptosporidium genus. The seasonal pattern of contamination and the related public health risks are of particular concern.

Detection of Giardia assemblage A in cats in Florence, Italy

In the present study, the assemblage of Giardia isolates from stray and owned cats was investigated. Faeces were randomly collected from 27 cats, screened by microscopy and examined by molecular methods that included DNA extraction, small subunit rRNA gene amplification and DNA sequence analysis. Ten cats were found to be infected with Giardia and harbouring cysts belonging to the zoonotic assemblage A. The cat-specific assemblage F was not found. Such a high proportion of Giardia assemblage A in cats may pose for a different geographical distribution of assemblages in the world. These findings provide insights that may be useful to map the epidemiological risk of the infection worldwide, as this may be instrumental in safeguarding human health.

First description of the endogenous life cycle of Hypoderma sinense affecting yaks and cattle in China

Larvae belonging to five species of Hypoderma spp. (Diptera, Oestridae) cause myiasis in wild and domestic ruminants that is characterized by migrations within deep tissues. In China hypodermosis is one of the most important arthropod diseases affecting ruminants and, moreover, represents a significant zoonosis, with numerous reports of Hypoderma spp. affecting farmers. Recently, a sixth species, Hypoderma sinense Pleske, has been rediscovered but the endogenous migration pathway within the host body is completely unknown and it represents a major constraint for the control of larval infection. In December 2003 a total of 165 larval stages of Hypoderma spp. were collected from different anatomical sites of 40 yaks slaughtered at an abattoir in the province of Gansu, China. The morphological characters and size of the recovered larvae were used to infer migratory routes and 45 specimens were also subjected to a polymerase chain reaction (PCR) assay of cox1 mtDNA and amplicons sequenced. All the larvae molecularly processed were identified as H. sinense and sequence identity was confirmed by a PCR-restriction fragment length polymorphism (PCR-RFLP) tool carried out using BfaI and HinfI endonucleases. The finding of H. sinense larvae only in the oesophagus or both in oesophagus and subcutaneous tissue of 12 and 15 animals, respectively, indicates that H. sinense larvae migrate through the oesophagus similarly to Hypoderma lineatum (De Villers). The description of the endogenous life cycle of H. sinense will help to determine the timing of specific treatment programmes to guarantee the improvement of animal welfare and health, thus resulting in an increase in livestock production in China.

Molecular cross-sectional survey of gastric habronemosis in horses

Gastric habronemosis of horses caused by Habronema microstoma and Habronema muscae (Nematoda, Spirurida) is characterized by catarrhal gastritis, diarrhoea, progressive weight loss and ulcers. Despite its importance in the equine industry and in clinical practice, knowledge of the epidemiology of this infection is still incomplete as diagnosis in live animals is challenging. A two-step semi-nested PCR assay using ribosomal DNA (rDNA) markers has recently been used for the molecular diagnosis in vivo of gastric habronemosis based on the detection of H. microstoma and/or H. muscae DNA in equine faeces. To evaluate the field efficacy of this assay, a molecular epidemiological survey was carried out on equid gastric habronemosis in central Italy. One hundred and fifty-three individual faecal samples were collected from live native horses and subjected to both coprological examination and the two-step semi-nested PCR. When flotation procedures were performed no horse tested positive for Habronema spp. larvated eggs while 96 animals (61.2%) were positive for other endoparasites (i.e. strongyles, oxyurids, ascarids). Two-step semi-nested PCR detected 86 samples (53.6%) that were positive for H. microstoma and/or H. muscae DNA. H. microstoma prevalences showed statistically significant differences; the highest prevalence was observed in horses infected by other gastrointestinal parasites and concomitantly by H. muscae. No statistical differences were found between the prevalence of Habronema spp. infection and sex, age, breeding management, and antiparasitic treatments. This field survey provided further information on habronemosis and its epidemiology.

Giardia, Cryptosporidium and the spectre of zoonosis: the Italian experience from land to sea

In the last decade, a major concern for the scientific community has been whether infected animals can serve as reservoirs of Giardia and Cryptosporidium infection for humans. Worldwide, prevalence studies and molecular tools have provided insights into the taxonomy and epidemiology of these protozoa in order to better understand such a relation. This paper presents data on the prevalence and molecular genotyping studies from several sample types from land to sea (humans, companion animals, sheep, cattle, goats, wastewaters, surface water, and shellfish) available in Italy. The contribution of Italian researchers to the international debate on the veterinary significance of these infections and their impact on public health is highlighted and the main objectives to be pursued in the future depicted.

Molecular evidence for Cryptosporidium infection in dogs in Central Italy

Two hundred and forty kennel and privately owned dogs were tested for a molecular epidemiological study on Cryptosporidium infection. Genomic DNA was extracted from individual faecal samples. All the DNA extracts were analysed with a PCR assay specific for a approximately 400-bp fragment internal to the gene encoding for the Cryptosporidium oocyst wall protein. The prevalence was 3.3% and it was higher in kennel dogs and in dogs with gastrointestinal symptoms. Cryptosporidium parvum was detected by sequencing analysis in six kennel dogs and one privately owned dog, and Cryptosporidium canis was detected in one kennel dog. This is the first investigation on the prevalence of Cryptosporidium in Italian dogs and has pointed to the existence of genotypes that may be of public health significance.

Epidemiology and biology of nematodofauna affecting Testudo hermanni, Testudo graeca and Testudo marginata in Italy

Tortoises of the genus Testudo living in Italy are Testudo hermanni, Testudo graeca and Testudo marginata. Although a great deal of information has been acquired on the internal medicine and surgery on these animals, little is known of their parasitological fauna. A survey on the presence of gastro-intestinal parasitic nematodes in tortoises bred in Italy was carried out to acquire extensive epidemiological data. Stool samples of 62 tortoises (37 T. hermanni hermanni, 13 T. graeca, 6 T. hermanni boettgeri and 6 T. marginata) were macroscopically examined and subjected to qualitative (flotation and Baermann techniques) and quantitative (McMaster technique) microscopic examinations. Adult nematodes were identified using morphological keys. Eggs of oxyurids (species indistinguishable) and adults of Alaeuris numidica, Mehdiella microstoma, Mehdiella uncinata, Tachygonetria longicollis, Tachygonetria conica and Tachygonetria palearcticus (Oxyurida, Pharyngodonidae); larvae and adults of Atractis dactyluris (Ascaridida, Atractidae); and eggs and adults of Angusticaecum holopterum (Ascaridida, Ascarididae) were identified in all animals >1 year, whereas all tortoises <1 year of age were parasite-free. Moreover, this study reports for the first time A. numidica and M. microstoma in T. marginata. This work shows that nematodes affecting tortoises are diffused in Italy and highlights the need to investigate their epidemiology more in depth.

Biology of Thelazia callipaeda (Spirurida, Thelaziidae) eyeworms in naturally infected definitive hosts

Thelazia callipaeda (Spirurida, Thelaziidae) eyeworm causes ocular infection in carnivores and humans in the Far East; this infection has been recently reported also in Europe--northern and southern Italy--in dogs, cats and foxes. The natural vector/s of T. callipaeda is/are unknown and the development of the nematode in its definitive hosts is limited to an experimental trial on dogs. To contribute new insights into the development of T. callipaeda in the definitive host in field conditions, eyeworms were collected from naturally infected dogs from an area with a high prevalence of infection (up to 60.14%) in the Basilicata region of southern Italy, from January 2002 to December 2003. Conjunctival secretions were also collected and examined for the presence of immature stages. The presence of blastomerized eggs throughout the period--except for the months from May to November--indicates a seasonality in the reproductive activity of T. callipaeda, coinciding with the presence/absence of the vector. In fact, 1st-stage larvae were found in the lachrymal secretions of dogs in summer (June--July 2002 and 2003), ready to be ingested by flies feeding about the eyes. The evidence of 4th-stage larvae in March 2002 and April, July and October 2003 may be accounted for by the presence of flies that act as intermediate hosts of T. callipaeda from early spring to early autumn. The presence of immature stages in October indicates an overlapping generation of nematodes and a 2nd cycle of vector infection. This basic knowledge of the development of T. callipaeda will hopefully help future epidemiological studies to identify the intermediate hosts and define the likely risk for vectors in field conditions.

Molecular characterization of Thelazia lacrymalis (Nematoda, Spirurida) affecting equids: a tool for vector identification

Equine thelaziosis caused by the eyeworm Thelazia lacrymalis is a parasitic disease transmitted by muscid flies. Although equine thelaziosis is known to have worldwide distribution, information on the epidemiology and presence of the intermediate hosts of T. lacrymalis is lacking. In the present work, a PCR-RFLP based assay on the first and/or second internal transcribed spacer (ITS1 and ITS2) of ribosomal DNA was developed for the detection of T. lacrymalis DNA in its putative vector(s). The sensitivity of the technique was also assessed. The restriction patterns obtained readily differentiated T. lacrymalis from four species of Musca (Diptera, Muscidae) (i.e. Musca autumnalis, Musca domestica, Musca larvipara and Musca osiris), which are potential vectors of equine eyeworms. The molecular assay presented herein is a useful tool to identify the intermediate host(s) of T. lacrymalis in natural conditions and to study its/their ecology and epidemiology.

Cryptosporidiumparvum oocysts in seawater clams (Chameleagallina) in Italy

Bivalves filter large volumes of water and can concentrate organisms which are pathogenic for humans and animals. Our aim was to evaluate the presence of Cryptosporidium spp. in clams from the Adriatic coast (Abruzzo region) and genetically characterize the oocysts isolated from the clams. From March to July 2003, 960 specimens of clams (Chamelea gallina) present in nature were collected at 500 m from the Tordino, Tronto, Vibrata and Vomano river mouths on the Adriatic sea. The haemolymph and tissues were extracted from the specimens (240 per river mouth) after the specimens had been identified, measured and weighed (live weight). Immunofluorescence tests (IFA) were performed on pools (n = 32) of samples and oocysts of Cryptosporidium spp. were detected in 23 pools of C. gallina. To identify the Cryptosporidium species, all the pools IFA-positive were tested by a PCR assay specific for the Cryptosporidium outer wall protein (COWP) gene. Positive amplicons then were sequenced and analysed. Two pools of clams were positive for Cryptosporidium parvum Genotype 2 (the "bovine" i.e. zoonotic genotype). This is the first time that C. parvum was found in clams from the Adriatic sea in Italy and the case might be of public health importance.

Prevalence and molecular characterization of Giardia duodenalis from sheep in central Italy

Giardiosis in domestic ruminants is an important parasitic disease and it has been shown to impair growth in lambs, thus constituting a disease of economic concern. In Europe, surveys on the prevalence of giardiosis in sheep are limited. In order to obtain additional information on the presence of giardiosis and on the potential zoonotic role of Giardia duodenalis affecting sheep in central Italy, faecal samples of 325 native sheep from 20 farms in Abruzzo region (Italy) were examined for the presence of Giardia and the isolates were genotyped and sequenced. G. duodenalis cysts were detected in five of the 325 sheep (1.5%) (mean of 450 cysts/g) coming from two farms. The 770-bp fragment of the glutamate dehydrogenase gene and the 753-bp fragment of the beta-giardin gene showed 100% homology with the Assemblage AI. This work suggests for the first time in Italy that sheep carry a Giardia genotype, which can be a potential public health hazard.

Semi-nested PCR for the specific detection of Habronema microstoma or Habronema muscae DNA in horse faeces

Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) are parasitic nematodes which infect the stomach and/or skin of equids. The accurate diagnosis of gastric habronemosis is central to studying its epidemiology, but data on its distribution and prevalence are lacking, mainly due to the limitations of clinical and coprological diagnosis in live horses. To overcome this constraint, a two-step, semi-nested PCR-based assay was validated (utilizing genetic markers in the nuclear ribosomal DNA) for the specific amplification of H. microstoma or H. muscae DNA from the faeces from horses (n = 46) whose gastrointestinal parasite status had been determined at autopsy and whose faeces were examined previously using a conventional parasitological approach. Of these horses examined at autopsy, some harboured adults of either H. microstoma (n= 19) or H. muscae (n =4), and others (n = 7) harboured both species. Most of them were also infected with other parasites, including strongylid nematodes (subfamilies Cyathostominae and Strongylinae), bots and/or cestodes; there was no evidence of metazoan parasites in 2 horses. Larvated spirurid eggs were detected in the faeces of 1 of the 30 horses (3.3 %) shown to be infected with Habronema at autopsy. For this set of 46 samples, the PCR assay achieved a diagnostic specificity of 100 % and a sensitivity of approximately 97 % (being able to specifically detect as little as approximately 0.02 fg of Habronema DNA). The specificity of the assay was also tested using a panel of control DNA samples representing horse, the gastric spirurid Draschia megastoma and 26 other species of parasites from the alimentary tract of the horse. H. microstoma, H. muscae and D. megastoma could be readily differentiated from one another based on the sizes of their specific amplicons in the PCR. The results of this study showed that the performance of the PCR for the diagnosis of gastric habronemosis was similar to that of autopsy but substantially better than the traditional coprological examination procedure used. The ability to specifically diagnose gastric habronemosis in equids should have important implications for investigating the epidemiology and ecology of H. microstoma and H. muscae.

Specific identification of Habronema microstoma and Habronema muscae (Spirurida, Habronematidae) by PCR using markers in ribosomal DNA

Gastric or cutaneous habronemosis caused by Habronema microstoma Creplin, 1849 and Habronema muscae Carter, 1865 is a parasitic disease of equids transmitted by muscid flies. There is a paucity of information on the epidemiology of this disease, which is mainly due to limitations with diagnosis in the live animal and with the identification of the parasites in the intermediate hosts. To overcome such limitations, a molecular approach, based on the use of genetic markers in the second internal transcribed spacer (ITS-2) of ribosomal DNA, was established for the two species of Habronema. Characterisation of the ITS-2 revealed sequence lengths and G+C contents of 296 bp and 29.5% for H. microstoma, and of 334 bp and 35.9% for H. muscae, respectively. Exploiting the sequence difference (approximately 40%) between the two species of nematode, primers were designed and tested by the polymerase chain reaction (PCR) for their specificity using a panel of control DNA samples from common equid endoparasites, and from host tissues, faeces or muscid flies. Effective amplification from each of the two species of Habronema was achieved from as little as 10 pg of genomic DNA. Hence, this molecular approach allows the specific identification and differentiation of the DNA from H. microstoma and H. muscae, and could thus provide a molecular tool for the specific detection of Habronema DNA (irrespective of developmental stage) from faeces, skin and muscid fly samples. The establishment of this tool has important implications for the specific diagnosis of clinical cases of gastric and cutaneous habronemosis in equids, and for studying the ecology and epidemiology of the two species of Habronema.

A THIRD SPECIES OF HYPODERMA (DIPTERA: OESTRIDAE) AFFECTING CATTLE AND YAKS IN CHINA: MOLECULAR AND MORPHOLOGICAL EVIDENCE

Cattle and yak hypodermosis in China is caused by Hypoderma bovis and H. lineatum, with a prevalence reaching up to 98-100% of the animals and maximum intensities exceeding 400 warbles for each animal. A third species, H. sinense, is also considered by Chinese researchers to affect livestock. The molecular characterization of the most variable region of the mitochondrial cytochrome oxidase I gene and of the ribosomal 28S gene has been performed for the third-stage larvae collected from cattle and yaks in China and identified (on the basis of the spinulation on the ventral side of the 10th segment) as H. bovis, H. lineatum, and H. sinense. Amplicons were digested with the HinfI and BfaI restriction enzymes, which provided diagnostic profiles to simultaneously differentiate the 3 Hypoderma species. Third-stage larvae of H. sinense were also examined by scanning electron microscopy, which revealed proper morphological characteristics different from those of H. bovis and H. lineatum. The molecular and morphological evidence herein reported support the existence of a third species of Hypoderma affecting cattle and yaks in China, and the results provide new tools for unequivocal identification of this species and present key components for the evaluation of its endogenous cycle and pathogenicity in animals and humans.

Genotyping of Cryptosporidium isolates from Chamelea gallina clams in Italy

Chamelea gallina clams collected from the mouths of rivers along the Adriatic Sea (central Italy) were found to harbor Cryptosporidium parvum (genotype 2), which is the lineage involved in zoonotic transmission. The clams were collected from the mouths of rivers near whose banks ruminants are brought to graze. This paper reports the environmental spread of C. parvum in Italy and highlights the fact that genotyping of seaborne Cryptosporidium isolates is a powerful tool with which to investigate the transmission patterns and epidemiology of this microorganism.

[Myiasis caused by Oestridae: serological and molecular diagnosis]

Myiasis-causing Oestridae (bot flies) infect several animal species world-wide, from palaearctic to subtropical/tropical areas. Oestrids affect livestock production causing abortion, reduced milk production, losses in weight and fertility, poor hide quality and an impairment of the host's immune system. In the last few years much research has been carried out on the immunology of these infestations, in order to acquire efficient and reliable diagnostic serological tools; the genome of the different species of Oestridae has been studied to further their molecular identification, taxonomy and phylogenesis. The immunodiagnostic methods for many myiasis causing Oestrids have proven to be a viable alternative to the clinical parasitological examination or the post-mortem examination. Numerous serological tests have been developed for the diagnosis of bovine hypodermosis caused by Hypoderma bovis and Hypoderma lineatum, and ELISAs using larval hypodermin C as the antigen are currently used on serum, individual and pooled milk samples to detect the presence of circulating anti-Hypoderma antibodies. In Italy the best period to sample the animals is November-January, since it is in this period that the antibody kinetics of the animals reaches a peak. Recently the efficacy of the ELISA test on pasteurized milk samples has been demonstrated, allowing the diagnosis of bovine hypodermosis also in areas where there is no information on the presence of the disease and the sampling of the animals is laborious. The cross-reactivity between Przhevalskiana silenus antigens and anti-Hypoderma antibodies led to assessing the usefulness of a simple and cost-effective ELISA for the diagnosis of goat warble fly infection. In particular, it has been demonstrated that infected goats display an antibody peak in November-December in blood and milk, thus making this period suitable for sampling. Although no extensive data is available on the immunology of sheep and goat oestrosis caused by Oestrus ovis, the efficacy of ELISA has been demonstrated by correlating serological results with clinical post-mortem examinations. No immunological techniques are currently used to diagnose gasterophilosis of equids and only one study reports the efficacy of ELISA for detecting anti-Gasterophilus antibodies in infected equids. Several studies have been conducted into the molecular characterization of the mitochondrial DNA (mtDNA)--in particular of the gene encoding for the cytochrome oxidase I (COI)--for many free-living and parasitic arthropods for diagnostic, taxonomic and phylogenetic purposes. As regards Oestridae causing myiasis, the first study features a PCR-RFLP assay of the most common Italian species (i.e. H. bovis, H. lineatum, Gasterophilus intestinalis, P. silenus, O. ovis), which showed clear genetic differences among the genera examined, but no inter-specific variation between the two species of Hypoderma considered. The molecular characterization of the most variable region of the COI gene (encoding for the region from E4 to the terminal COOH) was able to clearly differentiate H. bovis and H. lineatum. The E4-COOH region of the COI gene has been characterized for 18 oestrid species and from a taxonomical point of view, molecular data confirm the morphological classification, with the examined species divided into four subfamilies. New insights have also been gained on the molecular differentiation of the most common species of Hypoderma (i.e. H. bovis, H. lineatum, Hypoderma actaeon, Hypoderma diana and Hypoderma tarandi) and, in particular, the restriction enzyme BfaI, provides a diagnostic profile that can be used to simultaneously differentiate all the species examined. The characterization of the E4-COOH COI gene and the hypervariable region of the gene encoding for the ribosomal Isu revealed the identity of Hypoderma sinense as a new species, infecting cattle and yaks in China. Finally, the molecular analysis of the same mitochondrial and ribosomal regions showed that P. silenus, Przhevalskiana aegagri and Przhevalskiana crossii are morphotypes of the same species.

[Ecology of Thelazia spp. in cattle and their vectors in Italy]

The genus Thelazia (Spirurida, Thelaziidae) includes a cosmopolitan group of eyeworm spirurids responsible for ocular infections in domestic and wild animals and transmitted by different species of muscids. Bovine thelaziosis is caused by Thelazia rhodesi Desmarest 1828, Thelazia gulosa Railliet & Henry 1910, and Thelazia skrjabini Erschow 1928, which occur in many countries; T. gulosa and T. skrjabini have been reported mainly in the New World, while T. rhodesi is particularly common in the Old World. In Italy, T. rhodesi was reported in southern regions a long time ago and, recently, T. gulosa and T. skrjabini have been identified in autochthonous cattle first in Apulia and then in Sardinia. Thirteen species of Musca are listed as intermediate hosts of eyeworms, but only Musca autumnalis and Musca larvipara have been demonstrated to act as vectors of Thelazia in the ex-URSS, North America, ex-Czechoslovakia and more recently in Sweden. In Italy, after the reports of T. gulosa and T. skrjabini in southern regions, the intermediate hosts of bovine eyeworms were initially only suspected as the predominant secretophagous Muscidae collected from the periocular region of cattle with thelaziosis were the face flies, M. autumnalis and M. larvipara, followed by Musca osiris, Musca tempestiva and Musca domestica. The well-known constraints in the identification of immature eyeworms to species by fly dissection and also the time-consuming techniques used constitute important obstacles to epidemiological field studies (i.e. vector identification and/or role, prevalence and pattern of infection in flies, etc.). Molecular studies have recently permitted to further investigations into this area. A PCR-RFLP analysis of the ribosomal ITS-1 sequence was developed to differentiate the 3 species of Thelazia (i.e. T. gulosa, T. rhodesi and T. skrjabini) found in Italy, then a molecular epidemiological survey has recently been carried out in field conditions throughout five seasons of fly activity and has identified the role of M. autumnalis, M. larvipara, M. osiris and M. domestica as vectors of T. gulosa and of M. autumnalis and M. larvipara of T. rhodesi. Moreover, M. osiris was described, for the first time, to act as a vector of T. gulosa and M. larvipara of T. gulosa and T. rhodesi. The mean prevalence in the fly population examined was found to be 2.86%. The molecular techniques have opened new perspectives for further research on the ecology and epidemiology not only of Thelazia in cattle but also of other autochthonous species of Thelazia which have been also recorded in Italy, such as Thelazia callipaeda, which is responsible for human and canid ocular infection and Thelazia lacrymalis, the horse eyeworm whose epidemiological molecular studies are in progress.

[Animal echinococcosis in Italy: epidemiological update]

Cystic Echinococcosis (CE) is one of the most widespread parasitoses in the Mediterranean Region (MR). This is due to various factors, the most important being the close association between man, sheep and dogs in areas where open farming is practised. Although this disease has been known for several years and many studies have been carried out, nowadays in Italy there are no complete epidemiological data on its diffusion and distribution. The available data show that CE is mainly diffused in those districts where the sheep-dog cycle can be perpetuated, such as central and southern Italy, and the islands. Furthermore, no data are available on biomolecular characterisation of the strains of Echinococcus granulosus in Italy, apart form those in Sardinia, where the G1 (sheep-dog) and G7 (pig-dog) strains were recently isolated. One of the reasons why CE is a problem with no easy solution is undoubtedly the difficulty of making a certain diagnosis in the dog, the principal definitive host of E. granulosus.

Molecular epidemiological survey on the vectors of Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini (Spirurida: Thelaziidae)

A Polymerase Chain Reaction (PCR)- based assay developed for the specific identification of Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini (Nematoda, Spirurida), which cause bovine ocular thelaziosis, was evaluated for its usefulness in detecting the intermediate hosts and in estimating the infection prevalence of vectors in field conditions throughout 5 years (from 1997 to 2001). A total of 5190 flies were captured and identified as Musca larvipara, Musca osiris, Musca autumnalis, Musca tempestiva or Musca domestica. Genomic DNA was extracted from pools constituted by heads, thoraces, abdomens and wings of 10 flies of each species, and 2076 samples were subjected to a PCR assay to specifically detect the ribosomal ITS-1 sequence of bovine Thelazia. Amplicons were sequenced and subjected to digestion with CpoI restriction enzyme. M. autumnalis, M. larvipara, M. osiris and M. domestica species were shown to be PCR positive. T. gulosa was specifically detected by PCR in M. autumnalis, M. larvipara, M. osiris and M. domestica, whereas T. rhodesi is in M. autumnalis and M. larvipara. Of 27 positive samples, 23 were positive for T. gulosa and 4 for T. rhodesi, with a mean prevalence of 2·86% in the whole fly population collected. The highest mean prevalence values of infection were detected in M. autumnalis (4·46%) and M. larvipara (3·21%), and the former species was confirmed to be the vector of T. gulosa and T. rhodesi. This study is the first report of M. osiris as a vector of T. gulosa and M. larvipara as a vector of T. gulosa and T. rhodesi under natural conditions. The occurrence of Thelazia in fly populations in the Apulia region of Italy (in the 5 grazing seasons considered) indicates that cattle thelaziosis is enzootic in southern Italy. This molecular assay should be a useful epidemiological tool for assessing the role of different species of flies as intermediate hosts of thelaziae.

Efficacy of injectable and pour-on microdose ivermectin in the treatment of goat warble fly infestation by Przhevalskiana silenus (Diptera, Oestridae)

The prophylactic efficacy of microdoses of injectable and pour-on ivermectin formulations against larval stages of Przhevalskiana silenus was assessed in naturally infected goats in the region of Calabria (southern Italy).Sixty-eight goats from two goat farms were divided into five groups: one group remained untreated, while the other four groups were treated with microdoses of ivermectin (5 and 10 microg/kg injectable formulation and 10 and 20 microg/kg pour-on formulation). The microdoses of ivermectin were fully effective in the treatment of goat warble fly infestation (GWFI) as no larvae emerged from the warbles in the treated groups, while all the larvae emerged in the control groups. Irrespective of the type of formulation used, the difference between the treated groups and the control group was statistically significant (P< 0.001). By contrast, no statistical differences were found between the goats treated with the injectable formulation and those receiving the pour-on applications, and between the two doses of the injectable and pour-on formulations used. Given the plasma concentrations it attains at its lowest dose (0.052 - 0.042 ng/ml for the injectable formulation and 0.030 ng/ml for the pour-on) the injectable formulation seems to offer the most reliable route for the administration of ivermectin microdoses and it is acceptable for milk consumption. The introduction of ivermectin in the early eighties and the use of microdoses in some cases have made it possible to control cattle hypodermosis in large areas of Europe. As with cattle hypodermosis, the administration of ivermectin microdoses in goats is particularly interesting because of the low costs involved and the low levels of residues found in goat milk; it may thus constitute the basis for GWFI control campaigns in areas where the disease is prevalent.