Epidemiologic profile of hard ticks and molecular characterization of Rhipicephalus microplus infesting cattle in central part of Khyber Pakhtunkhwa, Pakistan.

Tick infestation is a major public and animal health concern causing significant financial losses, especially in tropical and subtropical regions of the world. This study aimed at investigating the epidemiologic profile of ticks infesting cattle and molecular identification of R. microplus in the centrally ignored part of Khyber Pakhtunkhwa, Pakistan. A total of 600 cattle from 20 farms were examined for the tick infestation, among them 358 (59.7%) cattle were infested with ticks. A total of 2118 nymph, larvae and adult tick stages were collected and morphologically identified followed by molecular confirmation of Rhipicephalus microplus. Host-based demographic and ecological parameter analysis revealed significantly higher tick infestation in adult, female, exotic, freely grazing, and with irregular/no acaricides treated cattle. The univariate logistic analysis showed that host age, gender, breed, acaricides use, and feeding method were significantly (P < 0.05) associated, whereas multivariate analysis revealed only host breed and feeding method were potential risk factors (P < 0.05) for tick infestation. Microscopy-based examination identified four different species of ticks including R. microplus (44.5%), Hyalomma anatolicum (38.5%), and Hyalomma marginatum (10.5%) and Hyalomma excavatum (6.5%). Tick infestation pattern showed that 55.9% of cattle was found co-infested with R. microplus and H. anatolicum followed by R. microplus and H. anatolicum and H. marginatum (29.3%) then R. microplus, H. anatolicum, H. marginatum, and H. excavatum (11.2%). Sequencing of the second internal transcribed spacer (ITS2-) and 16S rRNA gene fragments also confirmed the molecular identification of Rhipicephalus microplus. Phylogenetic analysis of ITS-2 revealed all sequences clustered in single clade of the R. microplus while the 16S rRNA nucleotide sequences showed that R. microplus in this study was clustered together in clade A along with other isolates from Pakistan, China, and India. The high tick infestation suggests the need for designing strategic and integrated control measures for ticks in order to ensure good health of domestic animals in this region of Pakistan.

Circulation of Rickettsia species and rickettsial endosymbionts among small mammals and their ectoparasites in Eastern Slovakia.

Bacteria belonging to the genus Rickettsia are known as causative agents of vector-borne zoonotic diseases, such as spotted fevers, epidemic typhus and endemic typhus. Different species of ticks, mites and fleas could act as reservoirs and arthropod vectors of different pathogenic Rickettsia species. The aim of this work was to establish active surveillance of Rickettsia spp. in mites, ticks and fleas collected from small mammals (rodents and shrews) in Eastern Slovakia. A total of 964 animal ear biopsies, 871 mites, 667 ticks and 743 fleas were collected from small mammals in the Kosice region, Eastern Slovakia. All specimens were identified using specialized taxonomic keys, and were conserved in ethanol until DNA extraction was performed. After DNA extraction, identification of Rickettsia species was performed by PCR-based methods. The total prevalence of rickettsiae from ear biopsies was 4.6% (95% CI, 3.2-5.9), in tested mites 9.3% (95% CI, 7.4-11.2), 17.2% (95% CI, 14.3-20.1) in I. ricinus ticks and 3.5% (95% CI, 2.2-4.8) in fleas. Sequence analysis of the partial gltA gene and Rickettsia helvetica-, Rickettsia slovaca-, Rickettsia raoultii- species specific real-time PCR tests revealed the presence of R. helvetica, R. slovaca, unidentified Rickettsia and rickettsial endosymbionts. These pathogenic and symbiotic species were confirmed in the following ectoparasite species-Laelaps jettmari, Haemogamasus nidi, Laelaps agilis and Eulaelaps stabularis mites, Ixodes ricinus ticks, Ctenophthalmus solutus, C. assimilis and Megabothris turbidus fleas infesting host-Apodemus agrarius, A. flavicollis, Microtus arvalis and Myodes glareolus small mammals. These results confirm the circulation of R. helvetica, R. slovaca, unidentified Rickettsia and rickettsial endosymbionts in mites, ticks and fleas collected on small mammals in the Kosice region, Eastern Slovakia.

Association of mechanical cleaning and a liquid preparation of diatomaceous earth in the management of poultry red mite, Dermanyssus gallinae (Mesostigmata: Dermanyssidae).

The poultry red mite (PRM), Dermanyssus gallinae, is an ectoparasite of great importance related to poultry farms worldwide. Problems associated with its control have led to the search for alternative treatments, especially using inert dust, which has recently been introduced into liquid formulations. Therefore, the objective of this work was to evaluate the acaricidal activity of a liquid diatomaceous earth (DE) preparation in the laboratory and its association with mechanical cleaning (brushing) in the field. In the laboratory it was first determined that a concentration of 10% DE would be necessary for field applications. The field experiment was conducted in a commercial poultry house. The 10% DE liquid preparation was administered in three applications and associated to mechanical cleaning. Then, 42 days after the first DE application, a population reduction of 94.7% was observed in relation to the initial population of mites. These results confirm the efficiency of DE applications in association with mechanical cleaning already adopted in poultry houses as an alternative for the control of D. gallinae, which can also contribute to avoiding mite resistance to chemical acaricides.

Dermanysuss gallinae attacks humans. Mind the gap!

Dermanyssus gallinae is a haematophagous ectoparasite primarily known as a pest of domestic and wild birds. It occasionally feeds on a range of mammals, and, more importantly, is of growing concern in human medicine. This review highlights mite attacks on people working with poultry, and updates the increasing incidence of dermanyssosis in urban environments in Europe. Although several cases of dermanyssosis have been documented, there are a number of reasons why diagnosis of D. gallinae infestations in humans is likely to be underestimated. Firstly, medical specialists are not well aware of D. gallinae infestations in humans. There is also a lack of collaboration with specialists from other disciplines. The problem is compounded by misdiagnoses and by the lack of diagnostic tools. We review the literature on human dermanyssosis cases in Europe, and also provide information on the epidemiology, clinical, histo-pathological and immunological aspects of dermanyssosis. We stress the need for improved recognition of this challenging infestation in humans, and provide straightforward recommendations for health practitioners, starting with collection of the correct anamnestic information and including appropriate management methods for case recognition and resolution. Finally, we indicate the most urgent areas to be addressed by future research. RESEARCH HIGHLIGHTS Dermanyssus gallinae is of growing concern in human medicine. Most physicians are not well aware of dermanyssosis in humans. Bio-epidemiological and clinical aspects of this ectoparasitosis are highlighted. Practical key actions for diagnosis and correct management of infestation in humans are provided.

Metaproteomics characterization of the alphaproteobacteria microbiome in different developmental and feeding stages of the poultry red mite Dermanyssus gallinae (De Geer, 1778).

The poultry red mite (PRM), Dermanyssus gallinae (De Geer, 1778), is a worldwide distributed ectoparasite and considered a major pest affecting the laying hen industry in Europe. Based on available information in other ectoparasites, the mite microbiome might participate in several biological processes and the acquisition, maintenance and transmission of pathogens. However, little is known about the role of PRM as a mechanical carrier or a biological vector in the transmission of pathogenic bacteria. Herein, we used a metaproteomics approach to characterize the alphaproteobacteria in the microbiota of PRM, and variations in its profile with ectoparasite development (nymphs vs. adults) and feeding (unfed vs. fed). The results showed that the bacterial community associated with D. gallinae was mainly composed of environmental and commensal bacteria. Putative symbiotic bacteria of the genera Wolbachia, C. Tokpelaia and Sphingomonas were identified, together with potential pathogenic bacteria of the genera Inquilinus, Neorickettsia and Roseomonas. Significant differences in the composition of alphaproteobacterial microbiota were associated with mite development and feeding, suggesting that bacteria have functional implications in metabolic pathways associated with blood feeding. These results support the use of metaproteomics for the characterization of alphaproteobacteria associated with the D. gallinae microbiota that could provide relevant information for the understanding of mite-host interactions and the development of potential control interventions. Research highlights Metaproteomics is a valid approach for microbiome characterization in ectoparasites. Alphaproteobacteria putative bacterial symbionts were identified in D. gallinae. Mite development and feeding were related to variations in bacterial community. Potentially pathogenic bacteria were identified in mite microbiota.

Comparison of Microbiomes between Red Poultry Mite Populations (Dermanyssus gallinae): Predominance of Bartonella-like Bacteria.

Blood feeding red poultry mites (RPM) serve as vectors of pathogenic bacteria and viruses among vertebrate hosts including wild birds, poultry hens, mammals, and humans. The microbiome of RPM has not yet been studied by high-throughput sequencing. RPM eggs, larvae, and engorged adult/nymph samples obtained in four poultry houses in Czechia were used for microbiome analyses by Illumina amplicon sequencing of the 16S ribosomal RNA (rRNA) gene V4 region. A laboratory RPM population was used as positive control for transcriptome analysis by pyrosequencing with identification of sequences originating from bacteria. The samples of engorged adult/nymph stages had 100-fold more copies of 16S rRNA gene copies than the samples of eggs and larvae. The microbiome composition showed differences among the four poultry houses and among observed developmental stadia. In the adults' microbiome 10 OTUs comprised 90 to 99% of all sequences. Bartonella-like bacteria covered between 30 and 70% of sequences in RPM microbiome and 25% bacterial sequences in transcriptome. The phylogenetic analyses of 16S rRNA gene sequences revealed two distinct groups of Bartonella-like bacteria forming sister groups: (i) symbionts of ants; (ii) Bartonella genus. Cardinium, Wolbachia, and Rickettsiella sp. were found in the microbiomes of all tested stadia, while Spiroplasma eriocheiris and Wolbachia were identified in the laboratory RPM transcriptome. The microbiomes from eggs, larvae, and engorged adults/nymphs differed. Bartonella-like symbionts were found in all stadia and sampling sites. Bartonella-like bacteria was the most diversified group within the RPM microbiome. The presence of identified putative pathogenic bacteria is relevant with respect to human and animal health issues while the identification of symbiontic bacteria can lead to new control methods targeting them to destabilize the arthropod host.

Prevalence of pathogenic bacteria in Ixodes ricinus ticks in Central Bohemia.

Bacteria associated with the tick Ixodes ricinus were assessed in specimens unattached or attached to the skin of cats, dogs and humans, collected in the Czech Republic. The bacteria were detected by PCR in 97 of 142 pooled samples including 204 ticks, i.e. 1-7 ticks per sample, collected at the same time from one host. A fragment of the bacterial 16S rRNA gene was amplified, cloned and sequenced from 32 randomly selected samples. The most frequent sequences were those related to Candidatus Midichloria midichlori (71% of cloned sequences), followed by Diplorickettsia (13%), Spiroplasma (3%), Rickettsia (3%), Pasteurella (3%), Morganella (3%), Pseudomonas (2%), Bacillus (1%), Methylobacterium (1%) and Phyllobacterium (1%). The phylogenetic analysis of Spiroplasma 16S rRNA gene sequences showed two groups related to Spiroplasma eriocheiris and Spiroplasma melliferum, respectively. Using group-specific primers, the following potentially pathogenic bacteria were detected: Borellia (in 20% of the 142 samples), Rickettsia (12%), Spiroplasma (5%), Diplorickettsia (5%) and Anaplasma (2%). In total, 68% of I. ricinus samples (97/142) contained detectable bacteria and 13% contained two or more putative pathogenic groups. The prevalence of tick-borne bacteria was similar to the observations in other European countries.

Understanding the biology and control of the poultry red mite Dermanyssus gallinae: a review.

Dermanyssus gallinae, the poultry red mite (PRM), is a blood-feeding ectoparasite capable of causing pathology in birds, amongst other animals. It is an increasingly important pathogen in egg layers and is responsible for substantial economic losses to the poultry industry worldwide. Even though PRM poses a serious problem, very little is known about the basic biology of the mite. Here we review the current body of literature describing red mite biology and discuss how this has been, or could be, used to develop methods to control PRM infestations. We focus primarily on the PRM digestive system, salivary glands, nervous system and exoskeleton and also explore areas of PRM biology which have to date received little or no study but have the potential to offer new control targets.

Rickettsia species in fleas collected from small mammals in Slovakia.

Epidemiological and epizootiological studies of Rickettsia felis and other Rickettsia spp. are very important, because their natural cycle has not yet been established completely. In total, 315 fleas (Siphonaptera) of 11 species of Ceratophyllidae, Hystrichopsyllidae and Leptopsyllidae families were tested for the presence of Rickettsia species and Coxiella burnetii with conventional and specific quantitative real-time PCR assays. Fleas were collected from five rodent hosts (Myodes glareolus, Apodemus flavicollis, Apodemus agrarius, Microtus subterraneus, Microtus arvalis) and three shrew species (Sorex araneus, Neomys fodiens, Crocidura suaveolens) captured in Eastern and Southern Slovakia. Overall, Rickettsia spp. was found in 10.8% (34/315) of the tested fleas of Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus uncinatus and Nosopsyllus fasciatus species. Infected fleas were coming from A. flavicollis, A. agrarius, and M. glareolus captured in Eastern Slovakia. C. burnetii was not found in any fleas. R. felis, Rickettsia helvetica, unidentified Rickettsia, and rickettsial endosymbionts were identified in fleas infesting small mammals in the Kosice region, Eastern Slovakia. This study is the first report of R. felis infection in C. solutus male flea collected from A. agrarius in Slovakia.

Molecular screening and genetic diversity of tick-borne pathogens associated with dogs and livestock ticks in Egypt.

BACKGROUND: The Middle East and North Africa (MENA) offer optimal climatic conditions for tick reproduction and dispersal. Research on tick-borne pathogens in this region is scarce. Despite recent advances in the characterization and taxonomic explanation of various tick-borne illnesses affecting animals in Egypt, no comprehensive examination of TBP (tick-borne pathogen) statuses has been performed. Therefore, the present study aims to detect the prevalence of pathogens harbored by ticks in Egypt. METHODOLOGY/PRINCIPAL FINDINGS: A four-year PCR-based study was conducted to detect a wide range of tick-borne pathogens (TBPs) harbored by three economically important tick species in Egypt. Approximately 86.7% (902/1,040) of the investigated Hyalomma dromedarii ticks from camels were found positive with Candidatus Anaplasma camelii (18.8%), Ehrlichia ruminantium (16.5%), Rickettsia africae (12.6%), Theileria annulata (11.9%), Mycoplasma arginini (9.9%), Borrelia burgdorferi (7.7%), Spiroplasma-like endosymbiont (4.0%), Hepatozoon canis (2.4%), Coxiella burnetii (1.6%) and Leishmania infantum (1.3%). Double co-infections were recorded in 3.0% (27/902) of Hy. dromedarii ticks, triple co-infections (simultaneous infection of the tick by three pathogen species) were found in 9.6% (87/902) of Hy. dromedarii ticks, whereas multiple co-infections (simultaneous infection of the tick by ≥ four pathogen species) comprised 12% (108/902). Out of 1,435 investigated Rhipicephalus rutilus ticks collected from dogs and sheep, 816 (56.9%) ticks harbored Babesia canis vogeli (17.1%), Rickettsia conorii (16.2%), Ehrlichia canis (15.4%), H. canis (13.6%), Bo. burgdorferi (9.7%), L. infantum (8.4%), C. burnetii (7.3%) and Trypanosoma evansi (6.6%) in dogs, and 242 (16.9%) ticks harbored Theileria lestoquardi (21.6%), Theileria ovis (20.0%) and Eh. ruminantium (0.3%) in sheep. Double, triple, and multiple co-infections represented 11% (90/816), 7.6% (62/816), and 10.3% (84/816), respectively in Rh. rutilus from dogs, whereas double and triple co-infections represented 30.2% (73/242) and 2.1% (5/242), respectively in Rh. rutilus from sheep. Approximately 92.5% (1,355/1,465) of Rhipicephalus annulatus ticks of cattle carried a burden of Anaplasma marginale (21.3%), Babesia bigemina (18.2%), Babesia bovis (14.0%), Borrelia theleri (12.8%), R. africae (12.4%), Th. annulata (8.7%), Bo. burgdorferi (2.7%), and Eh. ruminantium (2.5%). Double, triple, and multiple co-infections represented 1.8% (25/1,355), 11.5% (156/1,355), and 12.9% (175/1,355), respectively. The detected pathogens' sequences had 98.76-100% similarity to the available database with genetic divergence ranged between 0.0001 to 0.0009% to closest sequences from other African, Asian, and European countries. Phylogenetic analysis revealed close similarities between the detected pathogens and other isolates mostly from African and Asian countries. CONCLUSIONS/SIGNIFICANCE: Continuous PCR-detection of pathogens transmitted by ticks is necessary to overcome the consequences of these infection to the hosts. More restrictions should be applied from the Egyptian authorities on animal importations to limit the emergence and re-emergence of tick-borne pathogens in the country. This is the first in-depth investigation of TBPs in Egypt.

The first record of ostrich feather louse (Struthiolipeurus struthionis) collected from farmed ostriches (Struthio camelus) in the United Arab Emirates.

Background and Aim: Ostrich (Struthio camelus) farming in the United Arab Emirates (UAE) is a relatively new field of farming. Farmed ostriches are susceptible to ectoparasite infestation, which affects their production. This study was conducted to estimate the prevalence of ectoparasites on ostriches raised on a farm in Abu Dhabi Emirate. Materials and Methods: The feathers of 42 ostriches (26 females and 16 males) were collected and morphologically examined for ectoparasites. In total, 283 lice (89 males and 194 females) were collected from birds. However, there were no ticks or other ectoparasites. Lice were preserved in 1.5 mL tubes containing 70% ethanol and were later identified using taxonomic keys. The prevalence, mean intensity of infection, and mean abundance were estimated. Results: One louse species, Struthiolipeurus struthionis was identified. To the best of our knowledge, this is the first report of S. struthionis in ostriches raised in the UAE with an overall prevalence of 88%. The prevalence of lice was significantly higher in July (100%) than that in May (66.7%). Likewise, the mean intensity and abundance of lice were significantly higher in June (10.6 and 9.94, respectively) than in May (3.25 and 2.2, respectively). Conclusion: The high prevalence of lice poses a serious risk to ostrich farming by negatively affecting the health and productivity of ostriches.

Tick and Tick-Borne Diseases: New Problems Providing New Possible Solutions.

Ticks and tick-borne diseases are responsible for enormous losses in animal and human life, which do not seem to become better as new data show surprising connections [...].

A Participatory Approach in Assessing the Knowledge, Attitude, and Practices (KAP) of Stakeholders and Livestock Owners about Ticks and Tick-Borne Diseases from Sindh, Pakistan.

Ticks and tick-borne diseases (TTBDs) are responsible for significant losses in terms of treatment costs, decreased productivity (such as milk and meat), reduced reproductive ability, and financial crisis to livestock owners. In Pakistan, it is crucial to periodically assess the risk of TTBDs and ecological factors, potential causes of acaricidal resistance in tick fauna, and the intensive increase in the spread of TTBDs. Participatory epidemiological approaches are key to assessing the livestock owners' and stakeholders' knowledge, attitude, and practices (KAP) about TTBDs. The current study determined the KAP about ticks and tick-borne diseases of respondents from Sindh, Pakistan. A total of 240 respondents were interviewed from different ecological zones: among them, 42.5% (n = 102) of the respondents practiced the manual removal of ticks from animals, while acaricide usage was indicated by 137 respondents (57.0%) as occurring sometimes, 50 (20.8%) monthly, 41 (17.0%) fortnightly, and 12 (5%) weekly, during the peak infestation season. Ticks were 2.6 times [OR = 2.5 (95% Cl = 1.47-4.06)] and viruses were 1.89 times [OR = 188 (95% Cl = 1.09-2.9)] more likely to cause the development of disease in animals than any other pathogen. Despite the appropriate usage of acaricides, the knowledge of participants was inadequate. The findings of this study emphasize the need to take into account identified knowledge gaps and to take the initiative in carrying out appropriate education activities and extension programs to enhance the adoption of effective tick prevention and control strategies.

Nanopore sequencing identifies differentially methylated genes in the central nervous system in experimental autoimmune encephalomyelitis.

Multiple Sclerosis (MS) is a chronic autoimmune-mediated demyelinating disease of the central nervous system (CNS) that might be triggered by aberrant epigenetic changes in the genome. DNA methylation is the most studied epigenetic mechanism that participates in MS pathogenesis. However, the overall methylation level in the CNS of MS patients remains elusive. We used direct long-read nanopore DNA sequencing and characterized the differentially methylated genes in the brain from mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS. We identified 163 hypomethylated promoters and 327 hypermethylated promoters. These genomic alterations were linked to various biological processes including metabolism, immune responses, neural activities, and mitochondrial dynamics, all of which are vital for EAE development. Our results indicate a great potential of nanopore sequencing in identifying genomic DNA methylation in EAE and provide important guidance for future studies investigating the MS/EAE pathology.

Genetic diversity of vector-borne pathogens in ixodid ticks infesting dogs from Pakistan with notes on Ehrlichia canis, Rickettsia raoultii and Dirofilaria immitis detection.

BACKGROUND: Vector-/tick-borne pathogens (V/TBPs) pose a potential threat to human and animal health globally. Information regarding canine V/TBPs is scarce and no specific study has been conducted so far to explore the microbial diversity within ticks infesting dogs from Pakistan. Herein, this knowledge gap is addressed by assessing the genetic diversity and prevalence pattern of V/TBPs in ixodid ticks with special implications for public and canine health. METHODS: A total of 1150 hard ticks were collected from 300 dogs across central Khyber Pakhtunkhwa (KP), Pakistan. After morpho-molecular identification, 120 tick samples were screened for the presence of V/TBPs by amplifying 16S rRNA/gltA (Rickettsia/Ehrlichia and Wolbachia sp.), 18S rRNA (Theileria sp.) and cox1 (Dirofilaria sp.) genes through PCR followed by sequencing and phylogenetic study. RESULTS: In toto, 50 ixodid ticks (50/120, 41.7%) were found positive for V/TBPs DNA. The detected V/TBPs were categorized into five genera and eight species, viz. Ehrlichia (E. canis and Ehrlichia sp.), Rickettsia (R. massiliae, R. raoultii and Rickettsia sp.), Theileria (T. annulata), Dirofilaria (D. immitis) and Wolbachia (Wolbachia sp.). The pathogen prevalence patterns showed that R. massiliae was the most prevalent zoonotic V/TBP (19.5%), followed by E. canis (10.8%), Rickettsia sp. (7.5%), R. raoultii (6.7%), T. annulata (5.8%), D. immitis (5.8%), Wolbachia sp. (4.2%) and Ehrlichia sp. (3.3%), respectively. Among the screened tick species, most Rhipicephalus sanguineus sensu lato samples were found positive for V/TBP DNA (20/20,100%) followed by Rh. turanicus sensu stricto (13/20, 65%), Hyalomma dromedarii (8/20, 40%), Rh. haemaphysaloides (6/20, 30%), Hy. excavatum (2/20, 10%) and Rh. microplus (1/20, 5%). Co-occurrence of V/TBP was also detected in tick specimens (single V/TBP infection: 32 ticks; double and triple: 13 and 5 tick samples). The detected pathogens shared a phylogenetic relationship with similar isolates published in NCBI GenBank from Old and New World countries. CONCLUSION: Ixodid ticks infesting dogs harbor a diverse array of V/TBPs including zoonotic agents from Pakistan. Furthermore, the presence of D. immitis in ticks that infest dogs raises the possibility that this parasite has either attained its dead-end host (i.e. the tick) while feeding on dogs or has expanded its range of intermediate/paratenic hosts. Further research work is needed to investigate the epidemiology and confirm the vector competence of screened tick species for these pathogens from Pakistan.

Application of Cypermethrin-Coated ZnS and ZnO Nanoparticles against Rhipicephalus Ticks.

Rhipicephalus ticks are described as important ticks impacting the costs of livestock rearing and by-products sale. The prevalence and response of ticks towards cypermethrin sprays indicate the need to implement the rational use of acaricides. In our previous studies, ZnO nanoparticles were shown to inhibit the major life-cycle stages of Hyalomma ticks, indicative of promising application of nanomaterials against the hard ticks. The current study was designed to probe into one of alternative options to curtail Rhipicephalus ticks by employing cypermethrin-coated nanoparticles of ZnO (C-ZnO NPs) and ZnS (C-ZnS NPs). The nanocomposites showed a roughly spherical type of morphology and various size dimensions upon characterization using SEM and EDX. Female ovipositioning was declined up to only 48% in ZnS and up to 32% in ZnO NPs even after 28 days in vitro. Similarly, the larval hatching was also impacted, leading to a hatching percentage of 21% and 15% by application of C-ZnS NPs and C-ZnO NPs, respectively. The LC90 in female adult groups were 3.94 mg/L and 4.27 mg/L for the C-ZnO NPs and C-ZnS NPs groups, respectively. Similarly, the larval groups had LC90 of 8.63 and 8.95 mg/L for the C-ZnO NPs and C-ZnS NPs groups. The study is a proof of the concept for incorporating effective and safe nanocomposites as acaricides. The studies on the efficacy and spectrum of non-target effects of nanomaterial-based acaricides can further refine the research on finding novel alternatives for tick control.

First molecular confirmation of multiple zoonotic vector-borne diseases in pet dogs and cats of Hong Kong SAR.

In recent years, the incidence of vector-borne diseases (VBDs) has increased throughout the globe. In particular, tick-borne diseases (e.g., caused by Ehrlichia canis, E. ewingii, Anaplasma phagocytophilum, A. platys, Borrelia burgdorferi sensu stricto (s.s.) and Babesia gibsoni) and mosquito-borne diseases (e.g., caused by Dirofilaria immitis) diseases pose a burden on animal health. Nevertheless, there have been no studies undertaken on the occurrence of VBDs in pet dogs and cats in Hong Kong SAR. This study fills this gap, and is the first to determine the seroprevalence of major VBDs, such as those caused by D. immitis, E. canis, E. ewingii, A. phagocytophilum, A. platys and B. burgdorferi s.s, in dogs and cats through commercially available SNAP 4Dx plus testing. Infection by all these pathogens and Babesia sp. was further assessed through PCR and DNA sequencing. A total of 224 blood samples were collected from domestic dogs (n = 159) and cats (n = 65) in Hong Kong SAR during summer 2022. Hematocrit and platelet counts were determined in each blood sample and other hematological parameters were assessed using an automatic hematology analyzer and vortex the specimen for one to two minutes at or near the highest setting to minimize the clumping. All cat sera samples were negative for tested pathogens, but antibodies against some of the pathogens were detected in dog sera samples. Here, the highest figures were recorded for seroprevalence of E. canis/E. ewingii (10.7%), followed by D. immitis (5.7%), and A. phagocytophilum/A. platys (2.5%). No B. burgdorferi s.s. antibodies were detected in any of the dogs tested. Through molecular diagnostics, we detected the presence of B. gibsoni (3.7%), E. canis (3.1%), D. immitis (5.7%), and A. phagocytophilum (1.3%). Neighbor-Joining phylogenetic trees for vector-borne pathogens (i.e., genus Anaplasma sp.) showed 100% clustering to Japan, the USA and Germany, whereas genus Ehrlichia sp. showed 100% clustering to China, Turkey, Cuba, and Greece. Similarly, genus Babesia sp. clustered 100% to India, Sri Lanka and Austria, while D. immitis clustered in Iraq, South Korea, Portugal, France, the USA and Italy. This study provides the first evidence on the occurrence of tick-borne pathogens in pet dogs in Hong Kong SAR. Based on these findings, it is recommended that appropriate screening should be undertaken in domestic dogs to evaluate the prevalence of these pathogens and promote the timely control of VBDs.

Host-pathogen interaction in arthropod vectors: Lessons from viral infections.

Haematophagous arthropods can harbor various pathogens including viruses, bacteria, protozoa, and nematodes. Insects possess an innate immune system comprising of both cellular and humoral components to fight against various infections. Haemocytes, the cellular components of haemolymph, are central to the insect immune system as their primary functions include phagocytosis, encapsulation, coagulation, detoxification, and storage and distribution of nutritive materials. Plasmatocytes and granulocytes are also involved in cellular defense responses. Blood-feeding arthropods, such as mosquitoes and ticks, can harbour a variety of viral pathogens that can cause infectious diseases in both human and animal hosts. Therefore, it is imperative to study the virus-vector-host relationships since arthropod vectors are important constituents of the ecosystem. Regardless of the complex immune response of these arthropod vectors, the viruses usually manage to survive and are transmitted to the eventual host. A multidisciplinary approach utilizing novel and strategic interventions is required to control ectoparasite infestations and block vector-borne transmission of viral pathogens to humans and animals. In this review, we discuss the arthropod immune response to viral infections with a primary focus on the innate immune responses of ticks and mosquitoes. We aim to summarize critically the vector immune system and their infection transmission strategies to mammalian hosts to foster debate that could help in developing new therapeutic strategies to protect human and animal hosts against arthropod-borne viral infections.

Ticks Infesting Dogs in Khyber Pakhtunkhwa, Pakistan: Detailed Epidemiological and Molecular Report.

Ticks and tick-borne diseases are considered a major challenge for human and animal health in tropical, sub-tropical, and temperate regions of the world. However, only scarce information is available on the characterization of tick species infesting dogs in Pakistan. In this study, we present a comprehensive report on the epidemiological and phylogenetic aspects of ticks infesting dogs in Pakistan using the mitochondrial markers i.e. Cytochrome c oxidase subunit 1 (cox1) and 16S ribosomal RNA (16S rRNA) nucleotide sequences. A total of 300 dogs were examined and 1150 ixodid ticks were collected across central Khyber Pakhtunkhwa, Pakistan. The morpho-molecular characterization of hard ticks revealed the presence of two ixodid tick genera on dogs, i.e., Hyalomma and Rhipicephalus, including six tick species viz. Hyalomma dromedarii (15.9%), Hyalomma excavatum (3%), Rhipicephalus sanguineus s.l. (41.3%), Rhipicephalus turanicus s.s. (28.7%), Rhipicephalus haemaphysaloides (10.2%), and Rhipicephalus microplus (2%). The total prevalence of tick infestation in dogs was 61%. The district with the highest tick prevalence rate in dogs was Mardan (14.7%), followed by Peshawar (13%), Swabi (12%), Charsadda (11%), and Malakand (10.3%), respectively. Risk factors analysis indicated that some demographic and host management-associated factors such as host age, breed, exposure to acaricides treatment, and previous tick infestation history were associated with a higher risk of tick infestation on dogs. This is the first molecular report confirming the infestation of Hyalomma and Rhipicephalus tick species in the dog population from the study area. The present study also reported a new tick−host association between Hy. excavatum, Hy. dromedarii, and dogs. Phylogenetic analysis revealed that cox1 partial nucleotide sequences of Hy. excavatum in our dataset were 100% identical to similar tick specimens identified in Turkey, and those of Hy. dromedarii were identical to tick specimens from Iran. Whereas, Rh. haemaphysaloides and Rh. microplus' cox1 partial nucleotide sequences were identical to sequences previously published from Pakistan. Rhipicephalus turanicus s.s. 's cox1 isolates from the present study were 99.8−100% identical to Pakistani-reported isolates, and those of Rh. sanguineus s.l. were 100% identical to Chinese specimens. Results on the genetic characterization of ticks were further confirmed by 16S rRNA partial nucleotide sequences analysis, which revealed 100% identity between the tick isolates of this study and those of Hy. excavatum reported from Turkey; Hy. dromedarii specimens reported from Senegal; Rh. haemaphysaloides, Rh. microplus, and Rh. turanicus s.s., previously published from Pakistan, and Rh. sanguineus s.l., published from China. Furthermore, phylogenetic analysis showed that the Rh. sanguineus s.l. isolates of this study clustered with specimens of the tropical lineage with 7.7−10% nucleotide divergence from the specimens of the temperate lineage. Further molecular works need to be performed throughout Pakistan to present a more detailed map of tick distribution with information about dog host associations, biological characteristics, and pathogen competence.

A comparison of real-time PCR and reverse line blot hybridization in detecting feline haemoplasmas of domestic cats and an analysis of risk factors associated with haemoplasma infections.

BACKGROUND: Three species of feline haemoplasma are recognised: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus Mycoplasma turicensis (CMt). This study compared a reverse line blot hybridization (RLB) assay for simultaneous detection of Mhf, CMhm with three separate quantitative real-time polymerase chain reaction (qPCR) assays used for diagnosis of Mhf, CMhm and CMt. The RLB and qPCR assays were applied to DNA extracted from blood samples collected from 154 cats from Trinidad and Tobago. RESULTS: CMhm and Mhf DNA were detected using both RLB and qPCR. CMt DNA was detected by qPCR only. Comparing RLB and qPCR for the detection of CMhm DNA, 40 (26.3%) and 48 (31.6%) cats, respectively, were positive. The difference was more marked for Mhf, with RLB detecting a total of only 11 (7.2%) positive cats whereas qPCR detected 41 (27.0%) positive cats. Using qPCR as a gold standard, haemoplasma infected cats were more likely to be retrovirus positive (OR = 5.68, P = 0.02) and older (median age 5.5 years), than non-infected cats. In addition, CMhm positive cats were more likely to be male (OR = 3.4, P = 0.04). CONCLUSIONS: Overall the qPCR was more sensitive than RLB. In addition, age (median 5.5 years) and retrovirus positivity were risk factors for infection with the feline haemoplasmas in this study population. Further studies on feline haemoplasma infections in cats are needed to determine the significance of detecting small amounts of haemoplasma DNA, feline retrovirus infection and other associated risk factors on the clinical manifestation of disease.