Transgenerational effects of triazole fungicides on gene expression and egg compounds in non-exposed offspring: A case study using Red-Legged Partridges (Alectoris rufa)

Triazole fungicides are widely used to treat cereal seeds before sowing. Granivorous birds like the Red-legged Partridge (Alectoris rufa) have high exposure risk because they ingest treated seeds that remain on the field surface. As triazole fungicides can act as endocrine disruptors, affecting sterol synthesis and reproduction in birds several months after exposure, we hypothesized that these effects could also impact subsequent generations of exposed birds. To test this hypothesis, we exposed adult partridges (F0) to seeds treated at commercial doses with four different formulations containing triazoles as active ingredients (flutriafol, prothioconazole, tebuconazole, and a mixture of the latter two), simulating field exposure during late autumn sowing. During the subsequent reproductive season, two to four months after exposure, we examined compound allocation of steroid hormones, cholesterol, vitamins, and carotenoids in eggs laid by exposed birds (F1), as well as the expression of genes encoding enzymes involved in sterol biosynthesis in one-day-old chicks of this F1. One year later, F1 animals were paired again to investigate the expression of the same genes in the F2 chicks. We found changes in the expression of some genes for all treatments and both generations. Additionally, we observed an increase in estrone levels in eggs from partridges treated with flutriafol compared to controls, a decrease in tocopherol levels in partridges exposed to the mixture of tebuconazole and prothioconazole, and an increase in retinol levels in partridges exposed to prothioconazole. Despite sample size limitations, this study provides novel insights into the mechanisms of action of the previously observed effects of triazole fungicide-treated seeds on avian reproduction with evidence that the effects can persist beyond the exposure windows, affecting unexposed offspring of partridges fed with treated seeds. The results highlight the importance of considering long-term chronic effects when assessing pesticide risks to wild birds.

Molecular detection and associated risk factors of Anaplasma marginale, A. ovis and A. platys in sheep from Algeria with evidence of the absence of A. phagocytophilum

Anaplasma species are obligate intracellular rickettsial pathogens that cause significant diseases in animals and humans. Despite their importance, limited information on Anaplasma infections in Algeria has been published thus far. This study aimed to assess the infection rate, characterize Anaplasma species, and identify associated risk factors in selected sheep farms across Oum El Bouaghi region in Algeria. In 2018, we collected 417 blood samples from sheep (Ovis aries) and performed molecular characterization of Anaplasma species infecting these animals. This characterization involved the use of 16S rRNA, msp2, rpoB, and msp5 genes, which were analyzed through nested PCR, qPCR, cPCR, DNA sequencing, and subsequent phylogenetic analysis. Our findings revealed infection rates of 12.7 % for Anaplasma species detected, with Anaplasma ovis at 10.8 %, Anaplasma marginale at 1.7 %, and Anaplasma platys at 0.2 %. Interestingly, all tested animals were found negative for Anaplasma phagocytophilum. Statistical analyses, including the Chi-square test and Fisher exact test, failed to establish any significant relationships (p > 0.05) between A. ovis and A. platys infections and variables such as age, sex, sampling season, and tick infestation level. However, A. marginale infection exhibited a significant association with age (p < 0.05), with a higher incidence observed in lambs (5.2 %) compared to other age groups. Remarkably, this study represents the first molecular detection of A. platys and A. marginale in Algerian sheep. These findings suggest that Algerian sheep may serve as potential reservoirs for these pathogens. This research contributes valuable insights into the prevalence and characteristics of Anaplasma infections in Algerian sheep populations, emphasizing the need for further investigation and enhanced surveillance to better understand and manage these diseases.

Exploring the diversity of tick-borne pathogens: The case of bacteria (Anaplasma, Rickettsia, Coxiella and Borrelia) protozoa (Babesia and Theileria) and viruses (Orthonairovirus, tick-borne encephalitis virus and louping ill virus) in the European continent

Ticks are the main vectors for the transmission of bacterial, protist and viral pathogens in Europe affecting wildlife and domestic animals. However, some of them are zoonotic and can cause serious, sometimes fatal, problems in human health. A systematic review in PubMed/MEDLINE database was conducted to determine the spatial distribution and host and tick species ranges of a selection of tick-borne bacteria (Anaplasma spp., Borrelia spp., Coxiella spp., and Rickettsia spp.), protists (Babesia spp. and Theileria spp.), and viruses (Orthonairovirus, and flaviviruses tick-borne encephalitis virus and louping ill virus) on the European continent in a five-year period (November 2017 - November 2022). Only studies using PCR methods were selected, retrieving a total of 429 articles. Overall, up to 85 species of the selected tick-borne pathogens were reported from 36 European countries, and Anaplasma spp. was described in 37% (159/429) of the articles, followed by Babesia spp. (34%, 148/429), Borrelia spp. (34%, 147/429), Rickettsia spp. (33%, 142/429), Theileria spp. (11%, 47/429), tick-borne flaviviruses (9%, 37/429), Orthonairovirus (7%, 28/429) and Coxiella spp. (5%, 20/429). Host and tick ranges included 97 and 50 species, respectively. The highest tick-borne pathogen diversity was detected in domestic animals, and 12 species were shared between humans, wildlife, and domestic hosts, highlighting the following zoonotic species: Anaplasma phagocytophilum, Babesia divergens, Babesia microti, Borrelia afzelii, Borrelia burgdorferi s.s., Borrelia garinii, Borrelia miyamotoi, Crimean-Congo hemorrhagic fever virus, Coxiella burnetii, Rickettsia monacensis and tick-borne encephalitis virus. These results contribute to the implementation of effective interventions for the surveillance and control of tick-borne diseases.

A study of viral pathogens in bat species in the Iberian Peninsula: identification of new coronavirus genetic variants

Bats have long been associated with multiple pathogens, including viruses affecting humans such as henipaviruses, filoviruses, bunyaviruses and coronaviruses. The alpha and beta coronaviruses genera can infect most mammalian species. Among them, betacoronavirus SARS-CoV, MERS-CoV and SARS-CoV-2, which have caused the three major pandemics in the last two decades, have been proposed to originate in bats. In this study, 194 oral swabs from 22 bats species sampled in 19 locations of the Iberian Peninsula were analysed and characterized by three different PCR tests (coronavirus generic real-time RT-PCR, multiplex conventional PCR, and SARS-CoV-2 specific real-time RT-PCR) to detect bat coronaviruses. Screening with coronavirus generic PCR showed 102 positives out of 194 oral swabs analysed. Then, metabarcoding with multiplex PCR amplified 15 positive samples. Most of the coronaviruses detected in this study belong to alphacoronavirus (α-CoV) genus, with multiple alphacoronaviruses identified by up to five different genetic variants coexisting in the same bat. One of the positive samples identified in a Miniopterus schreibersii bat positive for the generic coronavirus PCR and the specific SARS-CoV-2 PCR was classified as betacoronavirus (-CoV) through phylogenetic analysis. These results support the rapid evolution of coronaviruses to generate new genomic potentially pathogenic variants likely through co-infection and recombination.

The Saharan antelope addax (Addax nasomaculatus) as a host for Hyalomma marginatum, tick vector of Crimean-Congo hemorrhagic fever virus

Tick infestation and pathogen prevalence in ticks infesting the Saharan antelope addax (Addax nasomaculatus) are factors that may constitute a risk for both human and animal health. In this study we describe season distribution of adult Hyalomma marginatum and analyzed the tick-borne pathogens and their seroprevalence in natural-living addax in Morocco. The results showed that addax is an important host species for H. marginatum adults. The seroprevalence of Bluetongue virus (BTV; 61.5-92.3%, n = 8/13-84/91), Coxiella burnetii (36.3-69.2%, n = 33/91-9/13) and Brucella spp. (0.0-4.8%, n = 0/50-2/42) was characterized in addax during various years (sampled animals per year, n = 13-91). Presence of Aigai virus (AIGV), a recent taxonomic differentiation of Crimean-Congo hemorrhagic fever virus (CCHFV) of 100% (4/4, years 2016 and 2017) together with Babesia ovis (75%, 3/4, year 2014), Anaplasma spp. (75%, 3/4, year 2014), Rickettsia spp. (50%, 2/4, year 2014) and Theileria spp. (25%, 1/4, year 2014) was observed in H. marginatum collected from the addax (4 pools of 10 adult ticks each). The results support the role of addax host in H. marginatum life cycle and exposure to AIGV and other tick-borne pathogens. The development of control interventions including anti-tick vaccines for wildlife species will contribute to the implementation of effective measures for the prevention and control of tick-borne diseases and might be relevant for the preservation of this threatened species and others such as Arabian oryx (Oryx leucoryx) and African elk (Taurotragus oryx) that share habitat.

Bagaza virus and Plasmodium spp. coinfection in red-legged partridges (Alectoris rufa), in Southern Spain 2019

Flaviviruses such as West Nile (WNV), Usutu (USUV) and Bagaza (BAGV) virus and avian malaria parasites are vector borne pathogens that circulate naturally between avian and mosquito hosts. WNV and USUV and potentially also BAGV constitute zoonoses. Temporal and spatial cocirculation and coinfection with Plasmodium spp., and West Nile virus has been documented in birds and mosquito vectors, and fatally USUV-infected passerines coinfected with Plasmodium spp. had more severe lesions. Also, WNV, USUV and BAGV have been found to cocirculate. Yet little is known about the interaction of BAGV and malaria parasites during consecutive or coinfections of avian hosts. Here we report mortality of free-living red-legged partridges in a hunting estate in Southern Spain that were coinfected with BAGV and Plasmodium spp. The outbreak occurred in the area where BAGV first emerged in Europe in 2010 and where cocirculation of BAGV, USUV and WNV was confirmed in 2011 and 2013. Partridges were found dead in early October 2019. Birds had mottled locally pale pectoral muscles, enlarged, congestive greenish-black tinged livers and enlarged kidneys. Microscopically congestion and predominantly mononuclear inflammatory infiltrates were evident and Plasmodium phanerozoites were present in the liver, spleen, kidneys, muscle and skin. Molecular testing and sequencing detected Plasmodium spp. and BAGV in different tissues of the partridges, and immunohistochemistry confirmed the presence and colocalization of both pathogens in the liver and spleen. Due to the importance of the red-legged partridge in the ecosystem of the Iberian Peninsula and as driver of regional economy such mortalities are of concern. Such outbreaks may reflect climate change related shifts in host, vector and pathogen ecology and interactions that could emerge similarly for other pathogens.

HEPA filters of portable air cleaners as a tool for the surveillance of SARS-CoV-2

Studies about the identification of SARS-CoV-2 in indoor aerosols have been conducted in hospital patient rooms and to a lesser extent in nonhealthcare environments. In these studies, people were already infected with SARS-CoV-2. However, in the present study, we investigated the presence of SARS-CoV-2 in HEPA filters housed in portable air cleaners (PACs) located in places with apparently healthy people to prevent possible outbreaks. A method for detecting the presence of SARS-CoV-2 RNA in HEPA filters was developed and validated. The study was conducted for 13 weeks in three indoor environments: school, nursery, and a household of a social health center, all in Ciudad Real, Spain. The environmental monitoring of the presence of SARS-CoV-2 was conducted in HEPA filters and other surfaces of these indoor spaces for a selective screening in asymptomatic population groups. The objective was to limit outbreaks at an early stage. One HEPA filter tested positive in the social health center. After analysis by RT-PCR of SARS-CoV-2 in residents and healthcare workers, one worker tested positive. Therefore, this study provides direct evidence of virus-containing aerosols trapped in HEPA filters and the possibility of using these PACs for environmental monitoring of SARS-CoV-2 while they remove airborne aerosols and trap the virus.

Bagaza Virus in Wild Birds, Portugal, 2021

Bagaza virus emerged in Spain in 2010 and was not reported in other countries in Europe until 2021, when the virus was detected by molecular methods in a corn bunting and several red-legged partridges in Portugal. Sequencing revealed high similarity between the 2021 strains from Portugal and the 2010 strains from Spain.

Fatal cases of bovine anaplasmosis in a herd infected with different Anaplasma marginale genotypes in southern Spain

The genus Anaplasma contains various species capable of causing disease in animals and humans. Anaplasma marginale is one of the main tick-borne pathogens of bovines in tropical and subtropical regions; however, these bacteria are now being detected more frequently in other regions of the world including Europe. In July 2017, abortions, mortality and morbidity in Retinta breed of cattle were investigated in southwestern Spain. Based on clinical signs, the provisional clinical diagnosis of bovine anaplasmosis was made. A molecular-phylogenetic approach was used to characterize A. marginale using multiple markers, including 16S rRNA, msp1a, msp4 and msp5 genes. The msp1α sequence was different from the previously described sequences from Spain as well as other countries. The isolates of A. marginale were classified as Genotype C, with two of the five tandem repeats in the amino acid sequences MSP1α being novel. The highest variability was observed in the four sequences of msp5 which was depicted in their clustering into multiple clades on a phylogenetic tree. Comparison of msp5 nucleotide sequences and the corresponding amino acid sequences revealed the co-existence of different strains in the same region. This study highlights the occurrence of clinical bovine anaplasmosis in an endemic region of Spain.

Characterization by Quantitative Serum Proteomics of Immune-Related Prognostic Biomarkers for COVID-19 Symptomatology

The COVID-19 pandemic caused by SARS-CoV-2 challenges the understanding of factors affecting disease progression and severity. The identification of prognostic biomarkers and physiological processes associated with disease symptoms is relevant for the development of new diagnostic and therapeutic interventions to contribute to the control of this pandemic. To address this challenge, in this study, we used a quantitative proteomics together with multiple data analysis algorithms to characterize serum protein profiles in five cohorts from healthy to SARS-CoV-2-infected recovered (hospital discharge), nonsevere (hospitalized), and severe [at the intensive care unit (ICU)] cases with increasing systemic inflammation in comparison with healthy individuals sampled prior to the COVID-19 pandemic. The results showed significantly dysregulated proteins and associated biological processes and disorders associated to COVID-19. These results corroborated previous findings in COVID-19 studies and highlighted how the representation of dysregulated serum proteins and associated BPs increases with COVID-19 disease symptomatology from asymptomatic to severe cases. The analysis was then focused on novel disease processes and biomarkers that were correlated with disease symptomatology. To contribute to translational medicine, results corroborated the predictive value of selected immune-related biomarkers for disease recovery [Selenoprotein P (SELENOP) and Serum paraoxonase/arylesterase 1 (PON1)], severity [Carboxypeptidase B2 (CBP2)], and symptomatology [Pregnancy zone protein (PZP)] using protein-specific ELISA tests. Our results contributed to the characterization of SARS-CoV-2–host molecular interactions with potential contributions to the monitoring and control of this pandemic by using immune-related biomarkers associated with disease symptomatology.

Challenges at the host-arthropod-coronavirus interface and COVID-19: a One Health approach

Background: The world faces the challenge posed by the interaction between hosts and Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) with potential role for arthropod vectors, and the effect of SARS-CoV-2 variants on acquired immunity, vaccine efficacy and coronavirus disease-19 (COVID-19) pandemic control. Proposal: The characterization of the role played by animal hosts and host-virus interactions is essential to address this challenge. Zoonotic (animal-to-human) and reverse zoonotic (human-to-animal) routes may be involved in virus transmission with a possible still unconfirmed role for arthropod vectors. Herein we propose to consider the risks posed by the possible role of arthropod vectors in COVID-19 and that immunity against SARS-CoV-2 may increase the risk for zoonotic virus transmission. These risks should be considered when evaluating vaccine efficacy and monitoring animal SARS-CoV-2 variants. Conclusion: Virus surveillance, epidemiology, sequencing and evaluation of susceptibility to antibodies and other protective immune mechanisms from vaccinated individuals should be improved. A One Health approach such as the one applied by our group SaBio is necessary for a more effective control of COVID-19 and prevention of future pandemics.

Comparative Proteomic Analysis of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) Tropical and Temperate Lineages: Uncovering Differences During Ehrlichia canis Infection

The tick vector Rhipicephalus sanguineus is established as a complex of closely related species with high veterinary-medical significance, in which the presence of different genetic, morphological, and biological traits has resulted in the recognition of different lineages within taxa. One of the most striking differences in the "temperate" and "tropical" lineages of R. sanguineus (s.l.) is the vector competence to Ehrlichia canis, suggesting that these ticks tolerate and react differently to pathogen infection. The present study addresses the SG and MG proteome of the R. sanguineus tropical and temperate lineages and compares their proteomic profile during E. canis infection. Batches of nymphs from the two lineages were allowed to feed on naïve and experimentally E. canis infected dogs and after molting, adults were dissected, and salivary glands and midgut tissues separated. Samples were screened for the presence of E. canis before proteomic analyses. The representation of the proteins identified in infected and non-infected tissues of each lineage was compared and gene ontology used for protein classification. Results highlight important differences in those proteomic profiles that added to previous reported genetic, biological, behavioral, and morphological differences, strengthening the hypothesis of the existence of two different species. Comparing infected and non-infected tissues, the results show that, while in midgut tissues the response to E. canis infection is similar in the salivary glands, the two lineages show a different pattern of protein representation. Focusing on the proteins found only in the infected condition, the data suggests that the cement cone produced during tick feeding may be implicated in pathogen infection. This study adds useful information to the debate on the controversial R. sanguineus systematic status, to the discussion related with the different vectorial competence occurring between the two lineages and identifies potential targets for efficient tick and tick-borne disease control.

Characterization of the anti-α-Gal antibody profile in association with Guillain-Barré syndrome, implications for tick-related allergic reactions

Humans evolved by losing the capacity to synthesize the glycan Galα1-3Galβ1-(3)4GlcNAc-R (α-Gal), which resulted in the capacity to develop a protective response mediated by anti-α-Gal IgM/IgG antibodies against pathogens containing this modification on membrane proteins. As an evolutionary trade-off, humans can develop the alpha-Gal syndrome (AGS), a recently diagnosed disease mainly associated with allergic reactions to mammalian meat consumption. The etiology of the AGS is the exposure to tick bites and the IgE antibody response against α-Gal-containing glycoproteins and glycolipids. The objective of this study was to characterize the anti-α-Gal antibody response in association with the immune-mediated peripheral neuropathy, Guillain-Barré syndrome (GBS), and compare it with different factors known to modulate the antibody response to α-Gal such as exposure to tick bites and development of allergic reactions in response to tick bites. The results showed a significant decrease in the IgM/IgG response to α-Gal in GBS patients when compared to healthy individuals. In contrast, the IgM/IgG levels to α-Gal did not change in patients with allergic reactions to tick bites. The IgE response was not affected in GBS patients, but as expected, the IgE levels significantly increased in individuals exposed to tick bites and patients with tick-associated allergies. These results suggest that the immune pathways of anti-α-Gal IgM/IgG and IgE production are independent. Further studies should consider the susceptibility to allergic reactions to tick bites in GBS patients.

Microbial community of Hyalomma lusitanicum is dominated by Francisella-like endosymbiont

Exploring tick associations with complex microbial communities and single-microbial partners, especially intracellular symbionts, has become crucial to understand tick biology. Of particular interest are the underlying interactions with biological consequences i.e. tick fitness, vector competence. In this study, we first sequenced the 16S rRNA bacterial phylogenetic marker in adult male ticks of Hyalomma lusitanicum collected from 5 locations in the province of Cáceres to explore the composition of its microbial community. Overall, 16S rRNA sequencing results demonstrated that the microbial community of H. lusitanicum is mostly dominated by Francisella-like endosymbionts (FLEs) (ranging from 52% to 99% of relative abundance) suggesting it is a key taxon within the microbial community and likely a primary endosymbiont. However, further research is required to explore the mechanisms underlying the interaction between FLEs and H. lusitanicum.

A dataset for the analysis of antibody response to glycan alpha-Gal in individuals with immune-mediated disorders

Humans evolved by losing the capacity to synthesize the glycan Galα1-3Galβ1-(3)4GlcNAc-R (α-Gal), which resulted in the development of a protective response mediated by anti-α-Gal IgM/IgG/IgA antibodies against pathogens containing this modification on membrane proteins. As an evolutionary trade-off, humans can develop the alpha-Gal syndrome (AGS), a recently diagnosed disease mediated by anti-α-Gal IgE antibodies and associated with allergic reactions to mammalian meat consumption and tick bites. However, the anti-α-Gal antibody response may be associated with other immune-mediated disorders such as those occurring in patients with COVID-19 and Guillain-Barré syndrome (GBS). Here, we provide a dataset (209 entries) on the IgE/IgM/IgG/IgA anti-α-Gal antibody response in healthy individuals and patients diagnosed with AGS, tick-borne allergies, GBS and COVID-19. The data allows correlative analyses of the anti-α-Gal antibody response with factors such as patient and clinical characteristics, record of tick bites, blood group, age and sex. These analyses could provide insights into the role of anti-α-Gal antibody response in disease symptomatology and possible protective mechanisms.

A dataset for the analysis of antibody response to glycan alpha-Gal in individuals with immune-mediated disorders

Humans evolved by losing the capacity to synthesize the glycan Galα1-3Galβ1-(3)4GlcNAc-R (α-Gal), which resulted in the development of a protective response mediated by anti-α-Gal IgM/IgG/IgA antibodies against pathogens containing this modification on membrane proteins. As an evolutionary trade-off, humans can develop the alpha-Gal syndrome (AGS), a recently diagnosed disease mediated by anti-α-Gal IgE antibodies and associated with allergic reactions to mammalian meat consumption and tick bites. However, the anti-α-Gal antibody response may be associated with other immune-mediated disorders such as those occurring in patients with COVID-19 and Guillain-Barré syndrome (GBS). Here, we provide a dataset (209 entries) on the IgE/IgM/IgG/IgA anti-α-Gal antibody response in healthy individuals and patients diagnosed with AGS, tick-borne allergies, GBS and COVID-19. The data allows correlative analyses of the anti-α-Gal antibody response with factors such as patient and clinical characteristics, record of tick bites, blood group, age and sex. These analyses could provide insights into the role of anti-α-Gal antibody response in disease symptomatology and possible protective mechanisms.

The antibody response to the glycan α-Gal correlates with COVID-19 disease symptoms

The coronavirus disease 2019 (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has affected millions of people worldwide. Characterization of the immunological mechanisms involved in disease symptomatology and protective response is important to progress in disease control and prevention. Humans evolved by losing the capacity to synthesize the glycan Galα1‐3Galβ1‐(3)4GlcNAc‐R (α‐Gal), which resulted in the development of a protective response against pathogenic viruses and other microorganisms containing this modification on membrane proteins mediated by anti‐α‐Gal immunoglobulin M (IgM)/IgG antibodies produced in response to bacterial microbiota. In addition to anti‐α‐Gal antibody‐mediated pathogen opsonization, this glycan induces various immune mechanisms that have shown protection in animal models against infectious diseases without inflammatory responses. In this study, we hypothesized that the immune response to α‐Gal may contribute to the control of COVID‐19. To address this hypothesis, we characterized the antibody response to α‐Gal in patients at different stages of COVID‐19 and in comparison with healthy control individuals. The results showed that while the inflammatory response and the anti‐SARS‐CoV‐2 (Spike) IgG antibody titers increased, reduction in anti‐α‐Gal IgE, IgM, and IgG antibody titers and alteration of anti‐α‐Gal antibody isotype composition correlated with COVID‐19 severity. The results suggested that the inhibition of the α‐Gal‐induced immune response may translate into more aggressive viremia and severe disease inflammatory symptoms. These results support the proposal of developing interventions such as probiotics based on commensal bacteria with α‐Gal epitopes to modify the microbiota and increase α‐Gal‐induced protective immune response and reduce severity of COVID‐19.

Multi-level analysis of exposure to triazole fungicides through treated seed ingestion in the red-legged partridge

Triazole fungicides are the most widely used products to treat cereal seeds. Granivorous birds, such as red-legged partridges (Alectoris rufa), which consume seeds left on the surface of fields after sowing, have a high risk of exposure. As triazole fungicides can affect sterol synthesis, we tested the hypothesis that treated seed consumption could alter the synthesis of sex hormones and reduce the reproductive capacity of partridges. We exposed adult partridges to seeds treated with four different formulations containing triazoles as active ingredients (flutriafol, prothioconazole, tebuconazole, and a mixture of the latter two) simulating a field exposure during the late autumn sowing season. All treatments produced biochemical changes and an overexpression of genes encoding for enzymes involved in the biosynthesis of sterols and steroid hormones, such as PMVK, ABCA1, MVD, PSCK9, DHCR7 and HSD17B7. Plasma levels of oestradiol were reduced in partridges exposed to tebuconazole. We also monitored reproduction 3 months after exposure (laying date, egg fertilization and hatching rates). We observed a 14-day delay in the laying onset of partridges that had been exposed to flutriafol as compared to controls. These results show that the consumption of seeds treated with triazole fungicides has the potential to affect granivorous bird reproduction. We recommend the evaluation of lagged reproductive effects as part of the protocols of environmental risk assessment of pesticides in wild birds in light of the effects resulting from the exposure to triazole-treated seeds.

Detection of new Crimean-Congo haemorrhagic fever virus genotypes in ticks feeding on deer and wild boar, Spain

Crimean-Congo haemorrhagic fever virus (CCHFV) is the causative agent of the severe tick-borne, often fatal, zoonotic Crimean-Congo haemorrhagic fever (CCHF), which is widely distributed worldwide. The CCHFV transmission to humans occurs through tick bite, crushing of engorged ticks or contact with infected host blood. Previously, CCHFV genotype Africa III was reported in Spain. Given the emergence of CCHF and the role of ticks in pathogen maintenance and transmission, we investigated the presence and genotype identity of the virus in tick species parasitizing abundant wild host species in south-western Spain. A total of 613 adult ticks were collected from hunter-harvested wild ungulates in twenty locations throughout south-western Spain. Ticks were identified, nucleic acids were extracted, RNA was analysed by a nested RT-PCR targeting CCHFV S segment, and the amplicons were sequenced. According to the 212-bp sequence amplified, the presence of CCHFV human genotype Europe V was detected in Hyalomma lusitanicum and Dermacentor marginatus ticks collected from red deer, fallow deer and Eurasian wild boar in different locations from south-western Spain. Genotype Africa IV was also detected in a H. lusitanicum tick collected from a red deer. The detection of CCHFV in different tick species collected from various wild hosts and localities provided strong evidence of widespread CCHFV presence in the region, suggesting that the circulation of the virus in Spain requires more attention. Additionally, the identification of the CCHFV genotype Europe V in ticks suggested that its introduction in Spain was probably from Eastern Europe.

Coronavirus in cat flea: findings and questions regarding COVID-19

The coronavirus disease 19 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people worldwide. Recent evidence raised the question about the possibility that cats may be a domestic host for SARS-CoV-2 with unknown implications in disease dissemination. Based on the fact that the domestic cat flea, Ctenocephalides felis, are abundant ectoparasites infesting humans, companion animals and wildlife and that coronavirus-like agents have been identified in the ectoparasite tick vector, Ixodes uriae of seabirds, herein we considered the presence of coronaviruses in general and SARS-CoV-2 in particular in C. felis. We identified coronavirus-derived and cell receptor angiotensin-converting enzyme RNA/proteins in C. felis. Although current evidence suggests that pets are probably dead-end-hosts with small risk of transmission to humans, our results suggested that cat flea may act as biological and/or mechanical vectors of SARS-CoV. Although preliminary, these results indicate a possibility of ectoparasites acting as reservoirs and vectors of SARS-CoV and related beta-coronavirus although with little disease risk due to systemic transmission route, low viremia, virus attenuation or other unknown factors. These results support the need to further study the role of animal SARS-CoV-2 hosts and their ectoparasite vectors in COVID-19 disease spread.

Tick and Host Derived Compounds Detected in the Cement Complex Substance

Ticks are obligate hematophagous arthropods and vectors of pathogens affecting human and animal health worldwide. Cement is a complex protein polymerization substance secreted by ticks with antimicrobial properties and a possible role in host attachment, sealing the feeding lesion, facilitating feeding and pathogen transmission, and protection from host immune and inflammatory responses. The biochemical properties of tick cement during feeding have not been fully characterized. In this study, we characterized the proteome of Rhipicephalus microplus salivary glands (sialome) and cement (cementome) together with their physicochemical properties at different adult female parasitic stages. The results showed the combination of tick and host derived proteins and other biomolecules such as α-Gal in cement composition, which varied during the feeding process. We propose that these compounds may synergize in cement formation, solidification and maintenance to facilitate attachment, feeding, interference with host immune response and detachment. These results advanced our knowledge of the complex tick cement composition and suggested that tick and host derived compounds modulate cement properties throughout tick feeding.

Clinical gamasoidosis and antibody response in two patients infested with Ornithonyssus bursa (Acari: Gamasida: Macronyssidae)

Blood-feeding ectoparasites constitute a growing burden for human and animal health, and animal production worldwide. In particular, mites (Acari: Gamasida) of the genera Dermanyssus (Dermanyssidae) and Ornithonyssus (Macronyssidae) infest birds and cause gamasoidosis in humans. The tropical fowl mite, Ornithonyssus bursa, is commonly found in tropical and subtropical countries but rarely reported in Europe. In this research we characterized the first two cases in Spain of clinical gamasoidosis diagnosed in patients infested with O. bursa, and investigated the IgE, IgM and IgG antibody response to mite proteins and the carbohydrate Galα1-3Galβ1-(3)4GlcNAc-R (α-Gal) involved in the tick-bite associated alpha-Gal syndrome (AGS). The results suggested that O. bursa is establishing across Mediterranean countries, and may increase the risk for gamasoidosis. The immune antibody response to mite proteins was higher for IgM and similar for IgE and IgG antibodies between patients and non-allergic control individuals exposed to mite or tick bites. The anti-α-Gal antibody levels were similar between patients and controls, a result supported by the absence of this carbohydrate in mites. These results suggested that mite bites do not correlate with antibody response to acarine proteins or α-Gal, and are not associated with the AGS.

Molecular identification of spotted fever group Rickettsia in ticks collected from dogs and small ruminants in Greece

Spotted fever group (SFG) Rickettsia are zoonotic and emerging pathogens with considerable impact in public and animal health. Greece is an endemic country of diseases caused by SFG Rickettsia. This work aims to evaluate the prevalence of SFG Rickettsia in ticks collected from domestic hosts including sheep, goats and dogs. Several genetic markers for bacterial genes, such as 16S rRNA, ompA, ompB, atpA, gltA, recA, dnaA and dnaK, were amplified and sequenced to accurately classified the rickettsial pathogens in the ticks. Taxonomy and species classification of the Rickettsia was achieved by combining phylogenetic and in silico digestion analysis of the gene sequences obtained. A total of 187 ticks were collected and classified at the species level as Ixodes gibosus, Dermacentor marginatus, Haemaphysalis parva, H. sulcata, H. punctata, Hyalomma scavatum, Rhipicephalus sanguineus, R. bursa and Rhipicephalus sp. The results showed that 7.5% of ticks were infected with at least one SFG Rickettsia including R. massiliae (n = 3), R. slovaca (n = 5), R. raoultii (n = 1) and R. hoogstraalii (n = 5), collected from sheep (n = 4), goats (n = 5) and dogs (n = 3). Molecular analysis revealed the presence of novel genetic variants of R. hoogstraalii (in H. sulcata and H. parva from goat and sheep) and R. raoultii (in D. marginatus from goat). These results proof the presence of SFG Rickettsia in domestic hosts in Greece, and support the need for continued monitoring, surveillance and further analyses of other hosts and study areas.

Characterization of the bacterial microbiota in wild-caught Ixodes ventalloi

Exploring the microbial diversity of ticks is crucial to understand geographical dispersion and pathogen transmission. Tick microbes participate in many biological processes implicated in the acquisition, maintenance, and transmission of pathogens, and actively promote host phenotypic changes, and adaptation to new environments. The microbial community of Ixodes ventalloi still remains unexplored. In this study, the bacterial microbiota of wild-caught I. ventalloi was characterized using shotgun-metagenomic sequencing in samples from unfed adults collected during December 2013-January 2014 in two locations from Sicily, Italy. The microbiota identified in I. ventalloi was mainly composed of symbiotic, commensal, and environmental bacteria. Interestingly, we identified the genera Anaplasma and Borrelia as members of the microbiota of I. ventalloi. These results advance our information on I. ventalloi microbiota composition, with potential implications in tick-host adaptation, geographic expansion, and vector competence.

Tick- and fly-borne bacteria in ungulates: the prevalence of Anaplasma phagocytophilum, haemoplasmas and rickettsiae in water buffalo and deer species in Central Europe, Hungary

Background

Hunting constitutes an important industry in Europe. However, data on the prevalence of vector-borne bacteria in large game animal species are lacking from several countries. Blood or spleen samples (239 and 270, respectively) were taken from red, fallow and roe deer, as well as from water buffaloes, mouflons and wild boars in Hungary, followed by DNA extraction and molecular analyses for Anaplasma phagocytophilum, haemoplasmas and rickettsiae.

Results

Based on blood samples, the prevalence rate of A. phagocytophilum infection was significantly higher in red deer (97.9%) than in fallow deer (72.7%) and roe deer (60%), and in all these compared to mouflons (6.3%). In addition, 39.2% of the spleen samples from wild boars were PCR positive for A. phagocytophilum, but none of the buffalos. Based on blood samples, the prevalence rates of both Mycoplasma wenyonii (Mw) and ‘Candidatus M. haemobos’ (CMh) infections were significantly higher in buffaloes (Mw: 91.2%; CMh: 73.3%) than in red deer (Mw: 64.6%; CMh: 45.8%), and in both of them compared to fallow deer (Mw: 30.3%; CMh: 9.1%) and roe deer (Mw: 20%; CMh: 1.5%). The prevalence of Mw and CMh infection significantly correlated with the body sizes of these hosts. Furthermore, Mw was significantly more prevalent than CMh in buffaloes, red and roe deer. Mycoplasma ovis was detected in mouflons, M. suis in wild boars, R. helvetica in one fallow deer and one mouflon, and an unidentified Rickettsia sp. in a fallow deer.

Conclusions

Forest-dwelling game animal species were found to be important carriers of A. phagocytophilum. In contrast, animals grazing grassland (i.e. buffaloes) were less likely to get infected with this Ixodes ricinus-borne pathogen. Water buffaloes, deer species, mouflons and wild boars harbored haemoplasmas that may affect domestic ungulates. Evaluated animals with larger body size had significantly higher prevalence of infection with haemoplasmas compared to smaller deer species. The above host species rarely carried rickettsiae.

Molecular survey of Rickettsial organisms in ectoparasites from a dog shelter in Northern Mexico

The objective of this study was to screen and identify rickettsial organisms in ectoparasites collected from dogs in a shelter in Gomez Palacio, Durango, Mexico. One hundred dogs were inspected for ectoparasites. All the dogs were parasitized with Rhipicephalus sanguineus ticks, three with Heterodoxus spiniger lice and one with Ctenocephalides felis fleas. DNA was extracted from the ectoparasites found on each dog, and PCR with the primers for the Anaplasmataceae 16S rRNA and citrate synthase gltA genes were performed. Eight DNA samples obtained from ticks, three from lice and one from fleas were positive to 16S rRNA. Only one sample from C. felis and one from H. spiniger were positive to gltA. Sequence analysis of amplified products from C. felis showed identity to Rickettsia felis, Wolbachia pipientis, and Wolbachia spp., while a sequence from H. spiniger showed identity to Wolbachia spp. Herein we report the molecular detection of R. felis, W. pipientis, and Wolbachia spp. in C. felis and H. spiniger in northern Mexico. These results contribute to the knowledge of the microorganisms present in ectoparasites from dogs in Mexico.

Identification and molecular characterization of spotted fever group rickettsiae in ticks collected from farm ruminants in Lebanon

Tick-borne diseases have become a world health concern, emerging with increasing incidence in recent decades. Spotted fever group (SFG) rickettsiae are tick-borne pathogens recognized as important agents of human tick-borne diseases worldwide. In this study, 88 adult ticks from the species Hyalomma anatolicum, Rhipicephalus annulatus, Rh. bursa, Rh. sanguineus sensu lato, and Rh. turanicus, were collected from farm ruminants in Lebanon, and SFG rickettsiae were molecularly identified and characterized in these ticks. The screening showed a prevalence of 68% for Rickettsia spp., including the species R. aeschlimannii, R. africae, R. massiliae and Candidatus R. barbariae, the latter considered an emerging member of the SFG rickettsiae. These findings contribute to a better knowledge of the distribution of these pathogens and demonstrate that SFG rickettsiae with public health relevance are found in ticks collected in Lebanon, where the widespread distribution of tick vectors and possible livestock animal hosts in contact with humans may favor transmission to humans. Few reports exist for some of the tick species identified here as being infected with SFG Rickettsia. Some of these tick species are proven vectors of the hosted rickettsiae, although this information is unknown for other of these species. Therefore, these results suggested further investigation on the vector competence of the tick species with unknown role in transmission of some of the pathogens identified in this study.

Combination of RT-PCR and proteomics for the identification of Crimean-Congo hemorrhagic fever virus in ticks

Crimean-Congo hemorrhagic fever (CCHF) is an emerging tick-borne zoonotic disease caused by the CCHF virus (CCHFV). In this study, an experimental approach combining RT-PCR and proteomics was used for the identification and characterization of CCHFV in 106 ticks from 7 species that were collected from small ruminants in Greece. The methodological approach included an initial screening for CCHFV by RT-PCR followed by proteomics analysis of positive and control negative tick samples. This novel approach allowed the identification of CCHFV-positive ticks and provided additional information to corroborate the RT-PCR findings using a different approach. Two ticks, Dermacentor marginatus and Haemaphysalis parva collected from a goat and a sheep, respectively were positive for CCHFV. The sequences for CCHFV RNA segments S and L were characterized by RT-PCR and proteomics analysis of tick samples, respectively. These results showed the possibility of combining analyses at the RNA and protein levels using RT-PCR and proteomics for the characterization of CCHFV in ticks. The results supported that the CCHFV identified in ticks are genetic variants of the AP92 strain. Although the AP92-like strains probably do not represent a high risk of CCHF to the population, the circulation of genetically diverse CCHFV strains could potentially result in the appearance of novel viral genotypes with increased pathogenicity and fitness.

Anaplasma phagocytophilum MSP4 and HSP70 Proteins Are Involved in Interactions with Host Cells during Pathogen Infection

Anaplasma phagocytophilum transmembrane and surface proteins play a role during infection and multiplication in host neutrophils and tick vector cells. Recently, A. phagocytophilum Major surface protein 4 (MSP4) and Heat shock protein 70 (HSP70) were shown to be localized on the bacterial membrane, with a possible role during pathogen infection in ticks. In this study, we hypothesized that A. phagocytophilum MSP4 and HSP70 have similar functions in tick-pathogen and host-pathogen interactions. To address this hypothesis, herein we characterized the role of these bacterial proteins in interaction and infection of vertebrate host cells. The results showed that A. phagocytophilum MSP4 and HSP70 are involved in host-pathogen interactions, with a role for HSP70 during pathogen infection. The analysis of the potential protective capacity of MSP4 and MSP4-HSP70 antigens in immunized sheep showed that MSP4-HSP70 was only partially protective against pathogen infection. This limited protection may be associated with several factors, including the recognition of non-protective epitopes by IgG in immunized lambs. Nevertheless, these antigens may be combined with other candidate protective antigens for the development of vaccines for the control of human and animal granulocytic anaplasmosis. Focusing on the characterization of host protective immune mechanisms and protein-protein interactions at the host-pathogen interface may lead to the discovery and design of new effective protective antigens.

High degree of mitochondrial gene heterogeneity in the bat tick species Ixodes vespertilionis, I. ariadnae and I. simplex from Eurasia

Background

Phylogeographical studies allow precise genetic comparison of specimens, which were collected over large geographical ranges and belong to the same or closely related animal species. These methods have also been used to compare ticks of veterinary-medical importance. However, relevant data are missing in the case of ixodid ticks of bats, despite (1) the vast geographical range of both Ixodes vespertilionis and Ixodes simplex, and (2) the considerable uncertainty in their taxonomy, which is currently unresolvable by morphological clues.

Methods

In the present study 21 ticks were selected from collections or were freshly removed from bats or cave walls in six European and four Asian countries. The DNA was extracted and PCRs were performed to amplify part of the cytochrome oxidase I (COI), 16S and 12S rDNA genes, followed by sequencing for identification and molecular-phylogenetic comparison.

Results

No morphological differences were observed between Ixodes vespertilionis specimens from Spain and from other parts of Europe, but corresponding genotypes had only 94.6 % COI sequence identity. An I. vespertilionis specimen collected in Vietnam was different both morphologically and genetically (i.e. with only 84.1 % COI sequence identity in comparison with I. vespertilionis from Europe). Two ticks (collected in Vietnam and in Japan) formed a monophyletic clade and shared morphological features with I. ariadnae, recently described and hitherto only reported in Europe. In addition, two Asiatic specimens of I. simplex were shown to differ markedly from European genotypes of the same species. Phylogenetic relationships of ticks showed similar clustering patterns with those of their associated bat host species.

Conclusions

Although all three ixodid bat tick species evaluated in the present study appear to be widespread in Eurasia, they exhibit pronounced genetic differences. Data of this study also reflect that I. vespertilionis may represent a species complex.

Infection and exposure to vector-borne pathogens in rural dogs and their ticks, Uganda

BACKGROUND

In rural parts of Africa, dogs live in close association with humans and livestock, roam freely, and usually do not receive prophylactic measures. Thus, they are a source of infectious disease for humans and for wildlife such as protected carnivores. In 2011, an epidemiological study was carried out around three conservation areas in Uganda to detect the presence and determine the prevalence of vector-borne pathogens in rural dogs and associated ticks to evaluate the risk that these pathogens pose to humans and wildlife.

METHODS

Serum samples (n = 105), blood smears (n = 43) and blood preserved on FTA cards (n = 38) and ticks (58 monospecific pools of Haemaphysalis leachi and Rhipicephalus praetextatus including 312 ticks from 52 dogs) were collected from dogs. Dog sera were tested by indirect immunofluorescence to detect the presence of antibodies against Rickettsia conorii and Ehrlichia canis. Antibodies against R. conorii were also examined by indirect enzyme immunoassay. Real time PCR for the detection of Rickettsia spp., Anaplasmataceae, Bartonella spp. and Babesia spp. was performed in DNA extracted from FTA cards and ticks.

RESULTS

99% of the dogs were seropositive to Rickettsia spp. and 29.5% to Ehrlichia spp. Molecular analyses revealed that 7.8% of the blood samples were infected with Babesia rossi, and all were negative for Rickettsia spp. and Ehrlichia spp. Ticks were infected with Rickettsia sp. (18.9%), including R. conorii and R. massiliae; Ehrlichia sp. (18.9%), including E. chaffeensis and Anaplasma platys; and B. rossi (1.7%). Bartonella spp. was not detected in any of the blood or tick samples.

CONCLUSIONS

This study confirms the presence of previously undetected vector-borne pathogens of humans and animals in East Africa. We recommend that dog owners in rural Uganda be advised to protect their animals against ectoparasites to prevent the transmission of pathogens to humans and wildlife.

Identification and characterization of a novel tick-borne flavivirus subtype in goats (Capra hircus) in Spain

In 2011, a neurological disease was reported in a herd of goats (Capra hircus) in Asturias, Spain. Initial sequencing identified the causative agent as louping ill virus (LIV). Subsequently, with the application of whole genome sequencing and phylogenetic analysis, empirical data demonstrates that the LIV-like virus detected is significantly divergent from LIV and Spanish sheep encephalitis virus (SSEV). This virus encoded an amino acid sequence motif at the site of a previously identified marker for differentiating tick-borne flaviviruses that was shared with a virus previously isolated in Ireland in 1968. The significance of these observations reflects the diversity of tick-borne flaviviruses in Europe. These data also contribute to our knowledge of the evolution of tick-borne flaviviruses and could reflect the movement of viruses throughout Europe. Based on these observations, the proposed name for this virus is Spanish goat encephalitis virus (SGEV), to distinguish it from SSEV.

Re-emergence of bovine piroplasmosis in Hungary: has the etiological role of Babesia divergens been taken over by B. major and Theileria buffeli?

BACKGROUND

The prevalence of bovine babesiosis caused by Babesia divergens has been declining during the past decades in northeastern Hungary, and no cases have been observed since 2008. Infections of cattle with B. major and Theileria buffeli were hitherto reported in southern and western Europe. In other parts of the globe, there is evidence of emergence and a growing clinical importance of T. buffeli and closely related genotypes of the T. orientalis complex.

FINDINGS

In a herd of 88 beef cattle kept in northeastern Hungary, bovine piroplasmosis was diagnosed in nine animals through the examination of blood smears or by molecular methods. B. major was identified in five animals, two of which died. In addition, four cattle harboured T. buffeli, and one of these animals was anaemic. Despite their presence, a contributory role of Anaplasma marginale and A. phagocytophilum could not be established in the disease cases.

CONCLUSIONS

In this study B. major and bovine theileriosis is reported for the first time in central-eastern Europe, where clinical cases were associated with a mild winter.

Oral vaccination with heat inactivated Mycobacterium bovis activates the complement system to protect against tuberculosis

Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar.

A systems biology approach to the characterization of stress response in Dermacentor reticulatus tick unfed larvae

Background

Dermacentor reticulatus (Fabricius, 1794) is distributed in Europe and Asia where it infests and transmits disease-causing pathogens to humans, pets and other domestic and wild animals. However, despite its role as a vector of emerging or re-emerging diseases, very little information is available on the genome, transcriptome and proteome of D. reticulatus. Tick larvae are the first developmental stage to infest hosts, acquire infection and transmit pathogens that are transovarially transmitted and are exposed to extremely stressing conditions. In this study, we used a systems biology approach to get an insight into the mechanisms active in D. reticulatus unfed larvae, with special emphasis on stress response.

Principal Findings

The results support the use of paired end RNA sequencing and proteomics informed by transcriptomics (PIT) for the analysis of transcriptomics and proteomics data, particularly for organisms such as D. reticulatus with little sequence information available. The results showed that metabolic and cellular processes involved in protein synthesis were the most active in D. reticulatus unfed larvae, suggesting that ticks are very active during this life stage. The stress response was activated in D. reticulatus unfed larvae and a Rickettsia sp. similar to R. raoultii was identified in these ticks.

Significance

The activation of stress responses in D. reticulatus unfed larvae likely counteracts the negative effect of temperature and other stress conditions such as Rickettsia infection and favors tick adaptation to environmental conditions to increase tick survival. These results show mechanisms that have evolved in D. reticulatus ticks to survive under stress conditions and suggest that these mechanisms are conserved across hard tick species. Targeting some of these proteins by vaccination may increase tick susceptibility to natural stress conditions, which in turn reduce tick survival and reproduction, thus reducing tick populations and vector capacity for tick-borne pathogens.

Control of tick infestations and pathogen prevalence in cattle and sheep farms vaccinated with the recombinant Subolesin-Major Surface Protein 1a chimeric antigen

BACKGROUND

Despite the use of chemical acaricides, tick infestations continue to affect animal health and production worldwide. Tick vaccines have been proposed as a cost-effective and environmentally friendly alternative for tick control. Vaccination with the candidate tick protective antigen, Subolesin (SUB), has been shown experimentally to be effective in controlling vector infestations and pathogen infection. Furthermore, Escherichia coli membranes containing the chimeric antigen composed of SUB fused to Anaplasma marginale Major Surface Protein 1a (MSP1a) (SUB-MSP1a) were produced using a simple low-cost process and proved to be effective for the control of cattle tick, Rhipicephalus (Boophilus) microplus and R. annulatus infestations in pen trials. In this research, field trials were conducted to characterize the effect of vaccination with SUB-MSP1a on tick infestations and the prevalence of tick-borne pathogens in a randomized controlled prospective study.

METHODS

Two cattle and two sheep farms with similar geographical locations and production characteristics were randomly assigned to control and vaccinated groups. Ticks were collected, counted, weighed and classified and the prevalence of tick-borne pathogens at the DNA and serological levels were followed for one year prior to and 9 months after vaccination.

RESULTS

Both cattle and sheep developed antibodies against SUB in response to vaccination. The main effect of the vaccine in cattle was the 8-fold reduction in the percent of infested animals while vaccination in sheep reduced tick infestations by 63%. Female tick weight was 32-55% lower in ticks collected from both vaccinated cattle and sheep when compared to controls. The seroprevalence of Babesia bigemina was lower by 30% in vaccinated cattle, suggesting a possible role for the vaccine in decreasing the prevalence of this tick-borne pathogen. The effect of the vaccine in reducing the frequency of one A. marginale msp4 genotype probably reflected the reduction in the prevalence of a tick-transmitted strain as a result of the reduction in the percent of tick-infested cattle.

CONCLUSIONS

These data provide evidence of the dual effect of a SUB-based vaccine for controlling tick infestations and pathogen infection/transmission and provide additional support for the use of the SUB-MSP1a vaccine for tick control in cattle and sheep.

Sequencing of modern Lepus VDJ genes shows that the usage of VHn genes has been retained in both Oryctolagus and Lepus that diverged 12 million years ago

Among mammals, the European rabbit (Oryctolagus cuniculus) has a unique mechanism of generating the primary antibody repertoire. Despite having over 200 VH genes, the VH1 gene, the most D-proximal VH gene, is used in 80-90 % of VDJ rearrangements, while the remaining 10-20 % is encoded by the VHn genes that map at least 100 Kb upstream of VH1. The maintenance of the VHn genes usage in low frequency in VDJ rearrangements has been suggested to represent a relic of an ancestral immunologic response to pathogens. To address this question, we sequenced VDJ genes for another leporid, genus Lepus, which separated from European rabbit 12 million years ago. Approximately 25 VDJ gene sequences were obtained for each one of three Lepus europaeus individuals. We found that Lepus also uses the VHn genes in 5-10 % of its VDJ rearrangements. Our results show that the VHn genes are a conserved ancestral polymorphism that has been maintained in the leporids genome and is being used for the generation of VDJ rearrangements by both modern Lepus and Oryctolagus.

Non-pet dogs as sentinels and potential synanthropic reservoirs of tick-borne and zoonotic bacteria

Blood samples were collected from 100 shepherd dogs, 12 hunting dogs and 14 stray dogs (apparently healthy) in southern Hungary to screen for the presence of emerging tick-borne pathogens. Based on real-time PCR results, 14 dogs (11%) had single or dual haemoplasma infection, and a same number of samples were positive for Anaplasma phagocytophilum. In one sample Coxiella burnetii was molecularly identified, and 20.3% of dogs seroconverted to the Q fever agent. Rickettsaemia (sensu stricto) was also detected in one animal. This is the first molecular evidence of autochthonous infection of dogs with the above pathogens in Hungary. The relatively high prevalence of haemoplasma and anaplasma infection among non-pet dogs is suggestive of a prolonged carrier status and bacteraemia of these animals rendering them epidemiologically significant as potential reservoirs and sentinels for tick-borne infections.

High prevalence of Hepatozoon-infection among shepherd dogs in a region considered to be free of Rhipicephalus sanguineus

Blood samples and ticks were collected from 100 shepherd dogs, 12 hunting dogs and 14 stray dogs in southern Hungary, in order to screen them for the presence of Hepatozoon spp. by PCR. Out of 126 blood samples, 33 were positive (26%). Significantly more shepherd dogs (31%) were infected, than hunting (8%) and stray dogs (7%). Three genotypes of Hepatozoon canis were identified by sequencing, differing from each other in up to six nucleotides in the amplified portion of their 18S rRNA gene. In Dermacentor marginatus larvae/nymphs and Dermacentor reticulatus nymphs, H. canis was present only if they had been collected from PCR-positive dogs, and the genotypes were identical in the ticks and their hosts. However, two Haemaphysalis concinna nymphs removed from a PCR-negative dog were found positive for H. canis, and the genotype detected in specimens of this tick species differed from that in the blood of their respective hosts. These results indicate that canine hepatozoonosis may be highly prevalent in regions where Rhipicephalus sanguineus is considered to be non-endemic. In addition, H. canis was identified for the first time in Hungary, as well as in D. marginatus, D. reticulatus and Ha. concinna ticks. Canine hepatozoonosis was significantly more prevalent west of the Danube river (where higher densities of red fox and golden jackal populations occur), suggesting a role of wild carnivores in its epidemiology.

Synanthropic birds associated with high prevalence of tick-borne rickettsiae and with the first detection of Rickettsia aeschlimannii in Hungary

The aim of this study was to analyze synanthropic birds as risk factors for introducing ticks and tick-borne pathogens into human settlements, with an emphasis on rickettsiae. Altogether 184 subadult ticks were found on 5846 birds. Tick infestation was most prevalent during the spring. In this sample group the majority of ticks were molecularly identified as Ixodes ricinus, and three individuals collected from the European robin as Hyalomma marginatum marginatum. The latter is the first molecularly confirmed occurrence of this species in Hungary. Rickettsia aeschlimannii was detected in H. marginatum, also for the first time in Hungary, and in ticks from an urbanized bird species north of the Mediterranean countries. The overall prevalence range of rickettsiae (including R. helvetica and R. monacensis) in ticks of synanthropic birds was 29-40%, exceeding that in questing ticks of relevant species reported earlier. Additionally, in specimens of I. ricinus, the presence of Borrelia burgdorferi sensu lato (s.l.), Anaplasma phagocytophilum, and a new Francisella-like genotype was also verified. Thus, it can be concluded that birds with urban or periurban habitats pose a high risk as tick carriers and reservoirs of zoonotic agents, especially of rickettsiae.

Louping ill in goats, Spain, 2011

Although louping ill affects mainly sheep, a 2011 outbreak in northern Spain occurred among goats. Histopathologic lesions and molecular genetics identified a new strain of louping ill virus, 94% identical to the strain from Britain. Surveillance is needed to minimize risk to domestic and wildlife species and humans.