The olfactory response of insect vectors such as phlebotomine sand flies is a key facet for investigating their interactions with vertebrate hosts and associated vector-borne pathogens. Such studies are mainly performed by assessing the electrophysiological response and the olfactory behaviour of these arthropods towards volatile organic compounds (VOCs) produced by hosts. Nonetheless, few studies are available for species of the subgenera Lutzomyia and Nyssomyia in South America, leaving a void for Old World sand fly species of the genus Phlebotomus. In this study, we evaluated the olfactory responses of Phlebotomus perniciosus, one of the most important vectors of Leishmania infantum in the Old World. To test the P. perniciosus behavioural response to VOCs, 28 compounds isolated from humans and dogs were assessed using electrophysiological (i.e., electroantennogram, EAG) and behavioural assays (i.e., Y-tube olfactometer). In the EAG trials, 14 compounds (i.e., acetic acid, nonanoic acid, 2-propanol, 2-butanol, pentanal, hexanal, nonanal, trans-2-nonenal, decanal, myrcene, p-cymene, verbenone, 2-ethyl-1-hexanol, and acetonitrile) elicited high antennal responses (i.e., ≥ 0.30 mV) in female sand flies, being those VOCs selected for the behavioural assays. From the 14 compounds tested in the Y-tube olfactometer, nonanal was significantly attractive for P. perniciosus females, whereas myrcene and p-cymene were significantly repellents (p < 0.05). The attraction indexes varied from 0.53 for nonanal (i.e., most attractive) to -0.47 to p-cymene (i.e., most repellent). Overall, our results shed light on the role of olfactory cues routing host seeking behaviour in P. perniciosus, with implications to develop sustainable sand fly monitoring as well as control in leishmaniasis endemic areas.
- MeSH
- chování zvířat účinky léků MeSH
- hmyz - vektory fyziologie účinky léků MeSH
- Leishmania infantum účinky léků fyziologie MeSH
- lidé MeSH
- Phlebotomus * fyziologie účinky léků MeSH
- psi MeSH
- těkavé organické sloučeniny * farmakologie chemie analýza MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Sand flies (Diptera: Psychodidae: Phlebotominae) are blood-feeding insects that transmit the protozoan parasites Leishmania spp. and various arboviruses. The Balkan region, including the Republic of Kosovo, harbours a diverse sand fly fauna. Vector species of Leishmania infantum as well as phleboviruses are endemic; however, recent data are scarce. We performed a cross-sectional study to update the current sand fly distribution in Kosovo and assess biological as well as environmental factors associated with sand fly presence. CDC light trapping was conducted at 46 locations in 2022 and 2023, specifically targeting understudied regions in Kosovo. Individual morphological species identification was supported by molecular barcoding. The occurrence data of sand flies was used to create distribution maps and perform environmental analyses, taking elevation, wind speed and climate-related factors into account. In addition, PCR-based blood meal analysis and pathogen screening were conducted. Overall, 303 specimens of six sand fly species were trapped, predominated by Phlebotomus neglectus (97%). Barcodes from eight of nine known endemic sand fly species were obtained. Combining our data with previous surveys, we mapped the currently known sand fly distribution based on more than 4000 specimens at 177 data points, identifying Ph. neglectus and Ph. perfiliewi as the predominant species. Environmental analyses depicted two geographical groups of sand flies in Kosovo, with notable differences between the species. In total, 223 blood meals of five sand fly species were analysed. Of seven identified host species, the predominant blood meal source was observed to be cattle, but the DNA of dogs and humans, among others, was also detected. This study assessed biological as well as ecological factors of sand fly occurrence, which should help better understand and evaluate potential hot spots of disease transmission in Kosovo.
- MeSH
- hmyz - vektory * fyziologie parazitologie MeSH
- Leishmania infantum fyziologie MeSH
- Phlebotomus * klasifikace fyziologie parazitologie MeSH
- průřezové studie MeSH
- psi MeSH
- Psychodidae fyziologie parazitologie MeSH
- rozšíření zvířat * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Kosovo MeSH
Equids may be infected by zoonotic Leishmania spp., including Leishmania infantum, in regions where canine leishmaniasis (CanL) is endemic, and Leishmania martiniquensis, which has been reported in horses from Central Europe. This study was designed to evaluate the occurrence of both Leishmania spp. among equids living in CanL endemic areas of Italy, as well as to identify dipteran vectors from the same habitats. From March to October 2023, blood, serum and tissue samples from skin lesions were collected from equids (n = 98; n = 56 donkeys and n = 42 horses) living in Italy, as well as sand flies and biting midges. Blood samples (n = 98) and skin lesions (n = 56) were tested for Leishmania spp. by conventional and real time PCRs and sera were tested by immunofluorescence antibody tests (IFAT) for both L. infantum and L. martiniquensis. Insects were morphologically identified, and female specimens (n = 268 sand flies, n = 7 biting midges) analyzed for Leishmania DNA, as well as engorged sand flies (n = 16) for blood-meal detection. Two animals with skin lesions (i.e., one donkey and one horse) scored positive for Leishmania spp. DNA, and 19 animals (i.e., 19.4%; n = 13 donkeys and n = 6 horses) were seropositive for L. infantum, with five of them also for L. martiniquensis. Most seropositive animals had no dermatological lesions (i.e., 68.4%) while both animals molecularly positive for Leishmania spp. scored seronegative. Of the 356 sand flies collected, 12 females (i.e., n = 8 Sergentomyia minuta; n = 3 Phlebotomus perniciosus, n = 1 Phlebotomus perfiliewi) were positive for Leishmania spp. DNA, and one out of seven biting midges collected was DNA-positive for L. infantum. Moreover, engorged sand flies scored positive for human and equine DNA. Data suggest that equids living in CanL endemic areas are exposed to Leishmania spp., but their role in the circulation of the parasite needs further investigations.
- MeSH
- Ceratopogonidae parazitologie MeSH
- endemické nemoci veterinární MeSH
- Equidae * parazitologie MeSH
- hmyz - vektory * parazitologie MeSH
- koně parazitologie MeSH
- Leishmania infantum izolace a purifikace genetika MeSH
- Leishmania * izolace a purifikace genetika klasifikace MeSH
- leishmanióza * veterinární epidemiologie parazitologie přenos MeSH
- nemoci koní parazitologie epidemiologie MeSH
- nemoci psů * parazitologie epidemiologie přenos MeSH
- psi MeSH
- Psychodidae parazitologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Itálie MeSH
BACKGROUND: In endemic areas of zoonotic leishmaniosis caused by L. infantum, early detection of Leishmania infection in dogs is essential to control the dissemination of the parasite to humans. The aim of this study was to evaluate the serological and/or molecular diagnostic performance of minimally and non-invasive samples (conjunctiva cells (CS) and peripheral blood (PB)) for monitoring Leishmania infection/exposure to Phlebotomus perniciosus salivary antigens in dogs at the beginning and the end of sand fly seasonal activity (May and October, respectively) and to assess associated risks factors. METHODS: A total of 208 sheltered dogs from endemic areas of leishmaniosis were screened. Leishmania DNA detection in PB on filter paper and CS was performed by nested-PCR (nPCR), while the detection of anti-Leishmania antibodies was performed using IFAT and ELISA. The exposure to P. perniciosus salivary antigens (SGH, rSP01 and rSP03B + rSP01) was measured by ELISA. RESULTS: Ninety-seven (46.6%) and 116 (55.8%) of the 208 dogs were positive to Leishmania antibodies or DNA by at least one test at the beginning and end of the sand fly season, respectively. IFAT and ELISA presented a substantial agreement in the serodiagnosis of leishmaniosis. Discrepant PB nPCR results were obtained between sampling points. Leishmania DNA was detected in CS of 72 dogs at the end of the phlebotomine season. The presence of antibodies to the parasite measured by ELISA was significantly higher in dogs presenting clinical signs compatible with leishmaniosis at both sampling points. Phlebotomus perniciosus salivary antibodies were detected in 179 (86.1%) and 198 (95.2%) of the screened dogs at the beginning and end of the phlebotomine season, respectively. CONCLUSIONS: The association between ELISA positivity and clinical signs suggests its usefulness to confirm a clinical suspicion. CS nPCR seems to be an effective and non-invasive method for assessing early exposure to the parasite. PB nPCR should not be used as the sole diagnostic tool to monitor Leishmania infection. The correlation between the levels of antibodies to P. perniciosus saliva and Leishmania antibodies suggests the use of a humoral response to sand fly salivary antigens as biomarkers of L. infantum infection.
- MeSH
- antigeny protozoální imunologie MeSH
- endemické nemoci prevence a kontrola MeSH
- hmyz - vektory parazitologie MeSH
- hmyzí proteiny imunologie MeSH
- imunoglobulin G krev MeSH
- konjunktiva cytologie parazitologie MeSH
- kousnutí a bodnutí hmyzem MeSH
- Leishmania infantum izolace a purifikace MeSH
- leishmanióza krev imunologie veterinární MeSH
- nemoci psů parazitologie prevence a kontrola přenos MeSH
- Phlebotomus parazitologie MeSH
- protilátky protozoální krev MeSH
- protozoální proteiny imunologie MeSH
- psi MeSH
- rizikové faktory MeSH
- sérologické testy MeSH
- slinné proteiny a peptidy imunologie MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Canine leishmaniosis caused by Leishmania infantum is a neglected zoonosis transmitted by sand flies like Phlebotomus perniciosus. Clinical signs and disease susceptibility vary according to various factors, including host immune response and breed. In particular, Ibizan hounds appear more resistant. This immunocompetence could be attributed to a more frequent exposure to uninfected sand flies, eliciting a stronger anti-sand fly saliva antibody response. METHODS: This study aimed to investigate the prevalence of anti-P. perniciosus saliva antibodies in Ibizan hounds and dogs of other breeds in the Leishmania-endemic area of Mallorca, Spain, and to correlate these antibody levels with clinical, immunological and parasitological parameters. Anti-sand fly saliva IgG was examined in 47 Ibizan hounds and 45 dogs of other breeds using three methods: P. perniciosus whole salivary gland homogenate (SGH) ELISA; recombinant protein rSP03B ELISA; and rSP03B rapid tests (RT). Additionally, diagnostic performance was evaluated between methods. RESULTS: Results indicate significantly higher anti-SGH antibodies (P = 0.0061) and a trend for more positive SGH ELISA and RT results in Ibizan hounds compared to other breeds. General linear model analysis also found breed to be a significant factor in SGH ELISA units and a marginally significant factor in RT result. Although infection rates were similar between groups, Ibizan hounds included significantly more IFN-γ producers (P = 0.0122) and papular dermatitis cases (P < 0.0001). Older age and L. infantum seropositivity were also considered significant factors in sand fly saliva antibody levels according to at least one test. Fair agreement was found between all three tests, with the highest value between SGH and rSP03B RT. CONCLUSIONS: To our knowledge, this is the first study elaborating the relationship between anti-P. perniciosus saliva antibodies and extensive clinical data in dogs in an endemic area. Our results suggest that Ibizan hounds experience a higher frequency of exposure to sand flies and have a stronger cellular immune response to L. infantum infection than other breed dogs. Additional sampling is needed to confirm results, but anti-P. perniciosus saliva antibodies appear to negatively correlate with susceptibility to L. infantum infection and could possibly contribute to the resistance observed in Ibizan hounds.
- MeSH
- chov MeSH
- endemické nemoci MeSH
- hmyzí proteiny imunologie MeSH
- imunoglobulin G imunologie MeSH
- leishmanióza imunologie veterinární MeSH
- náchylnost k nemoci MeSH
- nemoci psů imunologie parazitologie MeSH
- Phlebotomus imunologie MeSH
- psi MeSH
- slinné proteiny a peptidy imunologie MeSH
- sliny imunologie MeSH
- zoonózy parazitologie přenos MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Španělsko MeSH
BACKGROUND: Canine leishmaniasis (CanL) is a severe chronic disease caused by Leishmania infantum and transmitted by sand flies of which the main vector in the Western part of the Mediterranean basin is Phlebotomus perniciosus. Previously, an immunochromatographic test (ICT) was proposed to allow rapid evaluation of dog exposure to P. perniciosus. In the present study, we optimized the prototype and evaluated the detection accuracy of the ICT in field conditions. Possible cross-reactions with other hematophagous arthropods were also assessed. METHODOLOGY/PRINCIPAL FINDINGS: The ICT was optimized by expressing the rSP03B protein in a HEK293 cell line, which delivered an increased specificity (94.92%). The ICT showed an excellent reproducibility and inter-person reliability, and was optimized for use with whole canine blood which rendered an excellent degree of agreement with the use of serum. Field detectability of the ICT was assessed by screening 186 dogs from different CanL endemic areas with both the SGH-ELISA and the ICT, and 154 longitudinally sampled dogs only with the ICT. The ICT results corresponded to the SGH-ELISA for most areas, depending on the statistical measure used. Furthermore, the ICT was able to show a clear seasonal fluctuation in the proportion of bitten dogs. Finally, we excluded cross-reactions between non-vector species and confirmed favorable cross-reactions with other L. infantum vectors belonging to the subgenus Larroussius. CONCLUSIONS/SIGNIFICANCE: We have successfully optimized the ICT, now also suitable to be used with whole canine blood. The test is able to reflect the seasonal fluctuation in dog exposure and showed a good detectability in a field population of naturally exposed dogs, particularly in areas with a high seroprevalence of bitten dogs. Furthermore, our study showed the existence of favorable cross-reactions with other sand fly vectors thereby expanding its use in the field.
- MeSH
- hmyz - vektory parazitologie fyziologie MeSH
- imunoanalýza metody MeSH
- Leishmania infantum fyziologie MeSH
- leishmanióza krev diagnóza parazitologie veterinární MeSH
- myši inbrední BALB C MeSH
- nemoci psů krev diagnóza parazitologie MeSH
- Phlebotomus parazitologie fyziologie MeSH
- psi MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
A 2-year longitudinal study of enzyme-linked immunosorbent assay (ELISA) antibodies against Phlebotomus perniciosus and Phlebotomus papatasi (Diptera: Psychodidae) sandfly saliva was performed in 32 Beagle dogs treated preventively with an imidacloprid-permethrin topical insecticide in an endemic area in Spain. Dogs were grouped into three sandfly exposure groups according to the time of inclusion in the study. Assays analysed immunoglobulin G (IgG) against salivary gland homogenates (SGH) of both species and recombinant P. papatasi rSP32 and P. perniciosus rSP03B proteins in serum. The dogs were participating in a Leishmania infantum (Kinetoplastida: Trypanosomatidae) vaccine trial and were experimentally infected with the parasite in the second year. No dog acquired natural L. infantum infections during the first year, but most developed anti-saliva antibodies, and median log-transformed optical densities (LODs) were seasonal, mimicking those of local sandflies. This indicates that the repellent efficacy of the insecticide used is below 100%. Multi-level modelling of LODs revealed variability among dogs, autocorrelation and differences according to the salivary antigen and the dog's age. However, dog seroprevalence, estimated using pre-exposure LODs as cut-offs, was relatively low. This, and the fact that dogs did not become naturally infected with L. infantum, would support the efficacy and usefulness of this imidacloprid-permethrin topical insecticide in canine leishmaniasis control.
- MeSH
- biologické markery krev MeSH
- dusíkaté sloučeniny aplikace a dávkování farmakologie MeSH
- kousnutí a bodnutí hmyzem prevence a kontrola MeSH
- longitudinální studie MeSH
- neonikotinoidy aplikace a dávkování farmakologie MeSH
- permethrin aplikace a dávkování farmakologie MeSH
- Phlebotomus účinky léků MeSH
- protilátky krev účinky léků MeSH
- psi imunologie MeSH
- repelenty proti hmyzu aplikace a dávkování farmakologie MeSH
- zvířata MeSH
- Check Tag
- psi imunologie MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Španělsko MeSH
Hippobosca longipennis (Diptera: Hippoboscidae), the dog fly or dog louse fly, is an obligate blood-feeding ectoparasite of wild and domestic carnivores in Africa and the Middle East. Outside its typically known geographic range, H. longipennis has been reported occasionally on mainly domestic dogs in Asia and southern Europe, and infrequently in other areas (central Europe and the U.S.A.). This paper presents the first report of H. longipennis in Romania and the second record of Lipoptena fortisetosa (Diptera: Hippoboscidae), a potentially invasive species. Hippobosca longipennis was found on domestic dogs in two regions of the country (northern Romania in Maramures and southwestern Romania in Dobrogea) and on two road-killed wildcats in Maramures. Lipoptena fortisetosa was found on domestic dogs in Maramures. In both species identification was based on morphology and confirmed by barcoding of the cytochrome c oxidase subunit 1 gene. It is not clear for how long H. longipennis has been present in central Europe, nor if it was introduced (via the movement of domestic dogs or import of exotic carnivores) or present historically (Holocene remnants). This paper discusses the possible origins of H. longipennis in central Europe as its current distribution in the area is sparse and patchy.
- MeSH
- Diptera fyziologie MeSH
- infestace ektoparazity parazitologie veterinární MeSH
- nemoci psů parazitologie MeSH
- psi MeSH
- rozšíření zvířat * MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Serbia was a country endemic for leishmaniasis with rich and abundant sand fly fauna during the middle of the 20th century. After 1968, the disease was considered as eradicated, and as a consequence, all research on vectors and pathogens was neglected. The recent detection of Leishmania infantum in sand flies and confirmed cases of leishmaniasis in humans and dogs indicated the risk of re-emergence in Serbia. Also, for millions of refugees/immigrants, Serbia is a transit route between East-Mediterranean and Middle-East countries, and Central/North Europe, and it is under constant risk of vector and disease introduction. Primary objectives of this research were to determine which sand fly species are present around transit routes, whether they include vectors of the Leishmania spp. moreover, is/are Leishmania spp. present in the vectors. Surveys were conducted at 55 locations, organised in four clusters, which covered main immigrant routes and shelters/camps as well as tourist/trade transit routes. In total, 367 sand fly specimens were collected. Nine species were identified: Phlebotomus papatasi, P. perfiliewi, P. tobbi, P. neglectus, P. sergenti, P. alexandri, P. simici, P. balcanicus and P. mascittii. Detection of P. alexandri represents the first record in Serbia. The diversity of sand fly species increased while the number of collected specimens per night decreased during the period of research neglection. Phlebotomus neglectus, a proven vector of L. infantum, was a predominant species in all surveyed clusters, and in 56,52% of locations, it was the only species present. Although all detected species are regarded either as proven or suspected vectors of Leishmania spp., screening of females for Leishmania presence resulted negative. Our study provides insight into the significant changes of sand fly fauna in Serbia during the end of XX and beginning of XXI century. Diverse sand fly fauna in Serbia suggests that the establishment of new leishmaniasis foci is possible.
- MeSH
- emigrace a imigrace MeSH
- hmyz - vektory MeSH
- leishmanióza přenos MeSH
- lidé MeSH
- průzkumy a dotazníky MeSH
- psi MeSH
- Psychodidae * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Hosts repeatedly bitten by sand flies develop antibodies against sand fly saliva and screening of these immunoglobulins can be employed to estimate the risk of Leishmania transmission, to indicate the feeding preferences of sand flies, or to evaluate the effectiveness of vector control campaigns. Previously, antibodies to sand fly saliva were detected using whole salivary gland homogenate (SGH) or recombinant proteins, both of which also have their disadvantages. This is the first study on sand flies where short peptides designed based on salivary antigens were successfully utilized for antibody screening. METHODOLOGY/PRINCIPAL FINDINGS: Specific IgG was studied in hosts naturally exposed to Phlebotomus orientalis, the main vector of Leishmania donovani in East Africa. Four peptides were designed by the commercial program EpiQuest-B, based on the sequences of the two most promising salivary antigens, yellow-related protein and ParSP25-like protein. Short amino acid peptides were synthesised and modified for ELISA experiments. Specific anti-P. orientalis IgG was detected in sera of dogs, goats, and sheep from Ethiopia. The peptide OR24 P2 was shown to be suitable for antibody screening; it correlated positively with SGH and its specificity and sensitivity were comparable or even better than that of previously published recombinant proteins. CONCLUSIONS/SIGNIFICANCE: OR24 P2, the peptide based on salivary antigen of P. orientalis, was shown to be a valuable tool for antibody screening of domestic animals naturally exposed to P. orientalis. We suggest the application of this promising methodology using species-specific short peptides to other sand fly-host combinations.
- MeSH
- ELISA metody MeSH
- imunoglobulin G krev MeSH
- kozy MeSH
- ovce MeSH
- peptidy imunologie MeSH
- Phlebotomus imunologie MeSH
- plošný screening metody MeSH
- protilátky krev MeSH
- psi MeSH
- senzitivita a specificita MeSH
- slinné proteiny a peptidy imunologie MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Etiopie MeSH