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1.
Parasitol Res ; 123(8): 292, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102116

RESUMO

Ticks are blood ectoparasites that feed on domestic, wild animals and humans. They spread a variety of infections such as protozoa, viruses, and bacteria. Moreover, cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens. Therefore, accurate identification of ticks and detection of tick-borne pathogens is crucial. The main aim of this study was to identify and characterize ticks and tick-borne pathogens from selected villages in Greater Letaba Municipality, Limpopo Province, using morphological and molecular techniques. A total of 233 ticks were collected from cattle and identified morphologically using appropriate morphological keys. The following tick species were identified: Amblyomma hebraeum, Hyalomma rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Rhipicephalus evertsi evertsi, and Rhipicephalus sanguineus. Rhipicephalus spp. was the most common species accounting to 73.8% of the identified ticks. The genomic DNA was extracted from the whole tick for tick identification and from midguts of the ticks for the detection of tick-borne pathogens, followed by amplification and sequencing. A total of 27 samples were positive for tick-borne pathogens: 23 samples tested positive for Theileria and four samples tested positive for Ehrlichia. Anaplasma and Rickettsial OmpB could not be detected from any of the samples. There was no obvious grouping of ticks and tick-borne pathogens on the bases of their locality. The findings of this study confirm previous reports that indicated that cattle reared by smallholder farmers harbor various ticks and tick-borne pathogens of veterinary, public health, and economic importance. Regular monitoring of tick infestations in villages around the study areas is recommended to avoid disease outbreaks.


Assuntos
Doenças dos Bovinos , Infestações por Carrapato , Doenças Transmitidas por Carrapatos , Animais , Bovinos , África do Sul/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Genótipo , Ehrlichia/isolamento & purificação , Ehrlichia/genética , Ehrlichia/classificação , Anaplasma/isolamento & purificação , Anaplasma/genética , Anaplasma/classificação , Ixodidae/microbiologia , Ixodidae/parasitologia , Theileria/isolamento & purificação , Theileria/genética , Theileria/classificação , Feminino , Carrapatos/microbiologia , Carrapatos/parasitologia , Masculino
2.
Vet Res Commun ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145855

RESUMO

Ticks and tick-borne pathogens pose a great threat to human and animal health. The present study aimed to determine the prevalence of ticks that infest camels and investigate the presence of tick-borne pathogens in the blood of camels, associated ticks, and surrounding rodents as reservoirs. From 100 inspected camels, from different localities in the Giza governorate, 1000 ixodid ticks were collected; these ticks belonged to three genera: Hyalomma, Amblyomma, and Rhipicephalus. The genus Hyalomma was represented by four species, Hyalomma dromedarii was the most prevalent species (55.4%), followed by Hyalomma excavatum (22%), Hyalomma impeltatum (11.6%) and Hyalomma rufipes (2.8%). The genus Amblyomma was represented by two species, Amblyomma gemma (2.8%) and Amblyomma marmoreum (2.7%), while the genus Rhipicephalus was represented by only one species, Rhipicephalus pulchellus (2.7%). Ticks, camel blood, and rodents (total number 100 brown rats) are screened for tick-borne pathogens (Borrelia burgdorferi, Borrelia miyamotoi, Babesia sp., and Coxiella burnetii) using PCR. Camel blood was found to be infected with Borrelia burgdorferi (66.6%), Borrelia miyamotoi (55%), and Babesia sp. (11.6%). Coxiella burnetii DNA was detected in all the collected ticks but was not detected in the blood of camels or rodents. Borrelia miyamotoi was detected in 12.5% of H. impeltatum, 55% of Camels, and 6% of the rodents, which may indicate a proposed risk of dispersal of B. miyamotoi, the agent of tick-borne relapsing fever.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39148674

RESUMO

This study investigates the prevalence of Rickettsia spp. in Ixodes ricinus tick populations in different forest habitat types (broadleaf forest, mixed broadleaf and coniferous forest, and coniferous forest) in south-western Poland. During the survey periods from April to June 2018 and 2019 a total of 494 I. ricinus ticks, including 374 nymphs, 60 females and 60 males, were tested for Rickettsia infections by nested PCR targeting the gltA gene. The overall infection rate was 42.3%; however, we observed statistically significant year-to-year variation. Infection rates varied between tick developmental stages and were significantly influenced by forest habitat type. As assessed by a generalized linear mixed model (GLMM), the highest infection rates were observed in mixed broadleaf and coniferous forests, while coniferous forests had a significant negative effect on infection prevalence. DNA sequencing of selected samples confirmed the predominance of Rickettsia helvetica (91.2%) and less frequent Rickettsia monacensis (8.8%). This study suggests that the forest habitat types can influence Rickettsia spp. infection in tick populations; however, a comprehensive understanding of all factors influencing the level of infection requires future study.

4.
Infect Immun ; : e0021424, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120148

RESUMO

Lyme disease, the leading vector-borne disease in the United States and Europe, develops after infection with Borrelia burgdorferi sensu lato bacteria. Transmission of the spirochete from the tick vector to a vertebrate host requires global changes in gene expression that are controlled, in part, by the Rrp2/RpoN/RpoS alternative sigma factor cascade. Transcriptional studies defining the B. burgdorferi RpoS regulon have suggested that RpoS activates the transcription of paralogous family 52 (PFam52) genes. In strain B31, PFam52 genes (bbi42, bbk53, and bbq03) encode a set of conserved hypothetical proteins with >89% amino acid identity that are predicted to be surface-localized. Extensive homology among members of paralogous families complicates studies of protein contributions to pathogenicity as the potential for functional redundancy will obfuscate findings. Using a sequential mutagenesis approach, we generated clones expressing a single PFam52 paralog, as well as a strain deficient in all three. The single paralog expressing strains were used to confirm BBI42, BBK53, and BBQ03 surface localization and RpoS regulation. Surprisingly, the PFam52-deficient strain was able to infect mice and complete the enzootic cycle similar to the wild-type parental strain. Indeed, the presence of numerous pseudogenes that contain frameshifts or internal stop codons among the PFam52 genes suggests that they may be subjected to gene loss in B. burgdorferi's reduced genome. Alternatively, the lack of phenotype might reflect the limitations of the experimental mouse infection model.

5.
Biomed Res Int ; 2024: 4848451, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39035771

RESUMO

Tick-borne pathogens continue to infect humans and animals worldwide. By adapting to the movement of livestock, ticks facilitate the spread of these infectious pathogens. Humans in close contact with animals that could be amplifying hosts are especially at risk of being infected with tick-borne pathogens. This study involved the collection of dry blood spots (DBSs) to determine tick-borne pathogens occurring in slaughtered livestock and abattoir workers in Kumasi. This study employed the use of conventional PCR, RT-PCR, and Sanger sequencing to detect and identify the tick-borne pathogens. The resulting data was analysed using Stata version 13. A total of 175 DBSs were collected from goats (76), cattle (54), and sheep (45) in the Kumasi abattoir (130, 74.29%) and Akwatia Line slaughter slab (45, 25.71%). The pathogens identified were mostly bacterial including Anaplasma capra (9.71%), Anaplasma phagocytophilum (1.14%), and Rickettsia aeschlimannii (0.57.%). The only parasite identified was Theileria ovis (9.14%). A significant association was seen between A. capra (p < 0.001) infection and female sheep sampled from the Akwatia Line slaughter slab. Again, there was a significant association between T. ovis (p < 0.001) infections and female sheep from the Kumasi abattoir. From the human DBS (63) screened, the pathogens identified were all bacterial including Coxiella burnetii (1.89%), Rickettsia africae (1.89%), and R. aeschlimannii (1.89%). This study reports the first detection of R. aeschlimannii in livestock as well as the occurrence of the above-mentioned pathogens in humans in Ghana. Animals can serve as amplifying hosts for infectious pathogens; hence, there is an increased risk of infections among the abattoir workers. Continuous surveillance effort is essential, and abattoir workers need to protect themselves from tick bites and infectious tick-borne pathogens.


Assuntos
Matadouros , Doenças Transmitidas por Carrapatos , Zoonoses , Animais , Humanos , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia , Ovinos/parasitologia , Bovinos , Zoonoses/parasitologia , Zoonoses/microbiologia , Carrapatos/microbiologia , Carrapatos/parasitologia , Cabras/parasitologia , Cabras/microbiologia , Feminino , Masculino , Gado/parasitologia , Gado/microbiologia , Rickettsia/genética , Rickettsia/isolamento & purificação , Rickettsia/patogenicidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-39031268

RESUMO

PURPOSE: To determine the genomic feature of novel spotted fever-causing Rickettsia koreansis strain CNH17-7, which is different from R. japonica that is a causative agent for Japanese spotted fever (JSF), and to perform its comparative genomic analysis. METHODS: Whole genome sequencing (WGS) was performed on R. koreansis strain CNH17-7 by using the Illumina Miseq system. After WGS, assembly and annotation were done by SPAdes. Then, its genomic features were compared with 19 different Rickettsia species. Based on the average nucleotide identity (ANI) value, an unweighted pair group method with an arithmetic mean (UPGMA) dendrogram was generated. Following the dendrogram analysis, pan-and core-genome analysis was performed. Then additional comparative analyses with two genetically closest Rickettsia species were conducted based on gene repertoire. RESULTS: R. koreansis strain CNH17-7 has a chromosome consisting of 1,392,633 bp with GC content of 32.4%. The ANI-derived UPGMA showed that R. koreansis strain CNH17-7 is genetically close to R. japonica YH and R. heilongjiangensis 054 but is distinctively differentiated. The ANI value of R. koreansis strain CNH17-7 to R. japonica YH and R. heilongjiangensis 054 are 98.14% and 98.04% respectively, indicating R. koreansis strain CNH17-7 is sufficient to be classified as a new species. Other than ANI, R. koreansis strain CNH17-7 also contains novel CDS and its COG functional category proportion which is distinct compared to R. japonica YH and R. heilongjiangensis 054. CONCLUSION: We have revealed genomic features of the novel R. koreansis strain CNH17-7. Hence, we propose R. koreansis strain CNH17-7 as new Rickettsia species.

7.
Infect Dis Now ; 54(6): 104959, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39079570

RESUMO

OBJECTIVES: The Balkan Peninsula, acting as a crossroad between central Europe and the Middle East, presents diverse ecosystems supporting various tick species capable of transmitting TBDs. This study focuses on Serbia and North Macedonia, both endemic for TBDs, aiming to investigate human-biting ticks' prevalence, TBD prevalence, and major TBPs in blood samples. PATIENTS AND METHODS: This prospective observational study was conducted in 2022 at two medical centers, involving 45 patients from Novi Sad, Serbia, and 17 patients from Skopje, North Macedonia. All participants had either a tick still attached or had had one removed within the preceding 48 h. The study consisted in clinical evaluations of patients and testing of patient samples and ticks for tick-borne pathogens using a High-Throughput pathogen detection system based on microfluidic real-time PCR. In addition, the study assessed the genetic diversity of the identified pathogens. RESULTS: Ixodes ricinus was the most prevalent tick species, with varying infestation rates across various body parts. Tick species and feeding times differed between Novi Sad and Skopje. TBPs were prevalent, with Rickettsia spp. dominant in Skopje and a mix including Rickettsia aeschlimannii, Rickettsia monacensis, Anaplasma phagocytophilum, and Borrelia afzelii in Novi Sad. Subclinical bacteremia occurred in 8.06% of cases, mostly involving Anaplasma spp. Clinical manifestations, primarily local hypersensitivity reactions, were observed in six patients. Phylogenetic analysis confirmed R. aeschlimannii and R. monacensis identity, highlighting genetic differences in gltA gene sequences. CONCLUSIONS: This study sheds light on the prevalence and diversity of TBPs in tick-infested individuals from Serbia and North Macedonia, contributing valuable insights into the epidemiology of TBDs in the Balkan region.

8.
Parasite ; 31: 42, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39052012

RESUMO

Babesia species are intraerythrocytic protozoan parasites that infect a variety of hosts. The goal of this study was to evaluate the piroplasm species present in skunks in various states in the United States and determine whether there was any geographic variation. Spleen, whole blood, or blood on filter paper were received from Pennsylvania, Kentucky, North Carolina, South Carolina, Georgia, Missouri, Louisiana, Texas, Kansas, and California, and were tested for Babesia sp. We tested four species of skunks including striped skunk (Mephitis mephitis, n = 72), eastern spotted skunk (Spilogale putorius, n = 28), western spotted skunk (Spilogale gracilis, n = 15), and hog-nosed skunk (Conepatus leuconotus, n = 11). A PCR assay targeting the 18S rRNA region and cox1 region were used to determine if skunks were infected with piroplasms and for phylogenetic analyses. A total of 48.4% (61/126) of skunks tested positive for a Babesia species. Both the 18S and cox1 analysis supported a skunk-specific Babesia microti-like sp. of carnivores as well as a species in the B. microti complex that is phylogenetically unique from both B. microti of humans and the B. microti-like sp. of carnivores. In the 18S analysis, there was a third species of Babesia in hog-nosed skunks in the western piroplasm group. This study shows that at least three species of piroplasms occur in skunk species in the United States and further highlights the importance of phylogenetic analyses and the use of multiple gene targets when studying piroplasms.


Title: Diversité des Babesia spp. chez des mouffettes provenant d'États sélectionnés des États-Unis. Abstract: Les espèces de Babesia sont des protozoaires parasites intraérythrocytaires qui infectent divers hôtes. Le but de cette étude était d'évaluer les espèces de piroplasmes présentes chez les mouffettes dans divers états des États-Unis et de déterminer s'il existait une variation géographique. Des rates, du sang total ou du sang sur papier filtre ont été reçus de Pennsylvanie, du Kentucky, de Caroline du Nord, de Caroline du Sud, de Géorgie, du Missouri, de Louisiane, du Texas, du Kansas et de Californie, et ont été testés pour Babesia sp. Nous avons testé quatre espèces de mouffettes, dont la mouffette rayée (Mephitis mephitis, n = 72), la mouffette tachetée de l'Est (Spilogale putorius, n = 28), la mouffette tachetée de l'Ouest (Spilogale gracilis, n = 15) et la mouffette à nez plat (Conepatus leuconotus, n = 11). Un test PCR ciblant la région de l'ARNr 18S et la région cox1 a été utilisé pour déterminer si les mouffettes étaient infectées par des piroplasmes et pour des analyses phylogénétiques. Au total, 48,4 % (61/126) des mouffettes ont été testées positives pour une espèce de Babesia. Les analyses du 18S et du cox1 ont toutes deux confirmé une espèce de type Babesia microti de carnivores spécifique aux mouffettes ainsi qu'une espèce du complexe B. microti qui est phylogénétiquement unique à la fois par rapport à B. microti de l'homme et à l'espèce des carnivores. Dans l'analyse 18S, il y avait une troisième espèce de Babesia chez les mouffettes à nez plat du groupe des piroplasmes de l'ouest. Cette étude montre qu'au moins trois espèces de piroplasmes sont présentes chez les espèces de mouffettes aux États-Unis et souligne en outre l'importance des analyses phylogénétiques et de l'utilisation de plusieurs cibles génétiques lors de l'étude des piroplasmes.


Assuntos
Babesia , Babesiose , Mephitidae , Filogenia , RNA Ribossômico 18S , Babesiose/epidemiologia , Babesiose/parasitologia , Babesia/classificação , Babesia/isolamento & purificação , Babesia/genética , Animais , Estados Unidos/epidemiologia , RNA Ribossômico 18S/genética , Mephitidae/parasitologia , DNA de Protozoário , Variação Genética , Reação em Cadeia da Polimerase
9.
Pathogens ; 13(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39057783

RESUMO

Hard ticks (Ixodidae) play a critical role in transmitting various tick-borne diseases (TBDs), posing significant global threats to human and animal health. Climatic factors influence the abundance, diversity, and vectorial capacity of tick vectors. It is imperative to have a comprehensive understanding of hard ticks, pathogens, eco-epidemiology, and the impact of climatic changes on the transmission dynamics of TBDs. The distribution and life cycle patterns of hard ticks are influenced by diverse ecological factors that, in turn, can be impacted by changes in climate, leading to the expansion of the tick vector's range and geographical distribution. Vector competence, a pivotal aspect of vectorial capacity, involves the tick's ability to acquire, maintain, and transmit pathogens. Hard ticks, by efficiently feeding on diverse hosts and manipulating their immunity through their saliva, emerge as competent vectors for various pathogens, such as viruses, parasites and bacteria. This ability significantly influences the success of pathogen transmission. Further exploration of genetic diversity, population structure, and hybrid tick vectors is crucial, as they play a substantial role in influencing vector competence and complicating the dynamics of TBDs. This comprehensive review deals with important TBDs in India and delves into a profound understanding of hard ticks as vectors, their biology, and the factors influencing their vector competence. Given that TBDs continue to pose a substantial threat to global health, the review emphasizes the urgency of investigating tick control strategies and advancing vaccine development. Special attention is given to the pivotal role of population genetics in comprehending the genetic diversity of tick populations and providing essential insights into their adaptability to environmental changes.

10.
Pathogens ; 13(7)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39057813

RESUMO

Ticks are ectoparasites of a wide range of animals and are important vectors of numerous pathogens affecting humans, livestock, and pets. This study investigates possible correlations between selected factors, altitude, soil pH, and a factor called 'amount' (number of ticks examined in pooled samples) on the occurrence of I. ricinus ticks positive for selected tick-borne microorganisms. Questing I. ricinus ticks were collected in 2016 and 2017 across various altitudes, at two mountain ranges in central Slovakia. Tick pools were screened for the presence of Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato (Bbsl), Babesia/Theileria spp., Rickettsia spp., and tick-borne encephalitis virus (TBEV) using molecular methods. Regression analysis was employed to evaluate relationships between selected factors and the occurrence of vector-borne microorganisms. This study revealed a statistically significant influence of altitude on the occurrence of A. phagocytophilum; increasing altitude of the sampling site was associated with increased probability of pathogen occurrence. For Babesia/Theileria spp., neither altitude nor soil pH significantly affected pathogen occurrence. The occurrence of Bbsl was notably impacted by both altitude and soil pH; higher altitudes were associated with a decreased probability of pathogen presence, whereas higher soil pH increased the likelihood of pathogen occurrence. The presence of Rickettsia in a pooled sample was not affected by altitude and soil pH, but the 'amount' factor was a significant predictor, increasing the probability of pathogen detection. Neither altitude nor soil pH had a significant impact on TBEV occurrence. The regression models showed moderate goodness-of-fit levels to the data, underscoring their utility in examining the role of altitude and soil pH on pathogen occurrence. However, they explained only a small portion of the overall variance in pathogen occurrence, indicating the presence of other significant factors not covered in this study.

11.
Dev Comp Immunol ; 160: 105231, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39043336

RESUMO

The immune system of ticks, along with that of other invertebrates, is comparatively simpler than that of vertebrates, relying solely on innate immune responses. Direct antimicrobial defence is provided by the synthesis of antimicrobial peptides (AMPs), including defensins. The aim of this study was to investigate the differences in defensin genes expression between questing and engorged Ixodes ricinus (def1 and def2) and Dermacentor reticulatus (defDr) ticks, in the presence of selected pathogens: Borrelia spp., Rickettsia spp., Babesia spp., Anaplasma phagocytophilum, and Neoehrlichia mikurensis in the natural environment. After pathogen screening by PCR/qPCR, the expression of defensin genes in pathogen positive ticks and ticks without any of the tested pathogens, was analysed by reverse transcription qPCR. The results showed an increased expression of defensin genes in I. ricinus ticks after blood feeding and I. ricinus and D. reticulatus ticks during in cases of co-infection. In particular, the expression of defensins genes was higher in questing D. reticulatus than in questing and engorged I. ricinus ticks, when borreliae were detected. This study contributes to uncovering the expression patterns of defensin genes in the presence of several known tick pathogens, the occurrence of these pathogens and possible regulatory mechanisms of defensins in tick vector competence.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39070229

RESUMO

Ticks are known vectors of various pathogens, including bacteria, parasites and viruses, that impact both animal and human health. Improving knowledge of the distribution of tick-borne pathogens, combined with their early detection in ticks, are essential steps to fight against tick-borne diseases and mitigate their impacts. Here we give an overview of what are the common methods of pathogen detection in tick samples, including recent developments concerning how to handle tick samples, get access to tick-borne pathogens by chemical or physical disruption of the ticks, and methods used for the RNA/DNA extraction steps. Furthermore, we discuss promising tools that are developed for other sample types such as serum or blood to detect tick-borne pathogens, and those that could be used in the future for tick samples.

13.
Microbiol Spectr ; 12(8): e0125624, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39012114

RESUMO

Hyalomma marginatum is an invasive tick species recently established in mainland southern France. This tick is known to host a diverse range of human and animal pathogens. While information about the dynamics of these pathogens is crucial to assess disease risk and develop effective monitoring strategies, few data on the spatial dynamics of these pathogens are currently available. We collected ticks in 27 sites in the Occitanie region to characterize spatial patterns of H. marginatum-borne pathogens. Several pathogens have been detected: Theileria equi (9.2%), Theileria orientalis (0.2%), Anaplasma phagocytophilum (1.6%), Anaplasma marginale (0.8%), and Rickettsia aeschlimannii (87.3%). Interestingly, we found a spatial clustered distribution for the pathogen R. aeschlimannii between two geographically isolated areas with infection rates and bacterial loads significantly lower in Hérault/Gard departments (infection rate 78.6% in average) compared to Aude/Pyrénées-Orientales departments (infection rate 92.3% in average). At a smaller scale, R. aeschlimannii infection rates varied from one site to another, ranging from 29% to 100%. Overall, such high infection rates (87.3% on average) and the effective maternal transmission of R. aeschlimannii might suggest a role as a tick symbiont in H. marginatum. Further studies are thus needed to understand both the status and the role of R. aeschlimannii in H. marginatum ticks.IMPORTANCETicks are obligatory hematophagous arthropods that transmit pathogens of medical and veterinary importance. Pathogen infections cause serious health issues in humans and considerable economic loss in domestic animals. Information about the presence of pathogens in ticks and their dynamics is crucial to assess disease risk for public and animal health. Analyzing tick-borne pathogens in ticks collected in 27 sites in the Occitanie region, our results highlight clear spatial patterns in the Hyalomma marginatum-borne pathogen distribution and strengthen the postulate that it is essential to develop effective monitoring strategies and consider the spatial scale to better characterize the circulation of tick-borne pathogens.


Assuntos
Anaplasma phagocytophilum , Ixodidae , Rickettsia , Theileria , Animais , Rickettsia/isolamento & purificação , Rickettsia/genética , Rickettsia/classificação , França/epidemiologia , Ixodidae/microbiologia , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Theileria/genética , Theileria/isolamento & purificação , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/transmissão , Doenças Transmitidas por Carrapatos/epidemiologia , Anaplasma marginale/genética , Anaplasma marginale/isolamento & purificação , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Infecções por Rickettsia/transmissão , Infecções por Rickettsia/epidemiologia , Humanos , Bovinos , Feminino
14.
Infect Immun ; 92(8): e0024924, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38990046

RESUMO

Ticks are important vectors of disease, particularly in the context of One Health, where tick-borne diseases (TBDs) are increasingly prevalent worldwide. TBDs often involve co-infections, where multiple pathogens co-exist in a single host. Patients with chronic Lyme disease often have co-infections with other bacteria or parasites. This study aimed to create a co-infection model with Borrelia afzelii and tick-borne encephalitis virus (TBEV) in C3H mice and to evaluate symptoms, mortality, and pathogen level compared to single infections. Successful co-infection of C3H mice with B. afzelii and TBEV was achieved. Outcomes varied, depending on the timing of infection. When TBEV infection followed B. afzelii infection by 9 days, TBEV symptoms worsened and virus levels increased. Conversely, mice infected 21 days apart with TBEV showed milder symptoms and lower mortality. Simultaneous infection resulted in mild symptoms and no deaths. However, our model did not effectively infect ticks with TBEV, possibly due to suboptimal dosing, highlighting the challenges of replicating natural conditions. Understanding the consequences of co-infection is crucial, given the increasing prevalence of TBD. Co-infected individuals may experience exacerbated symptoms, highlighting the need for a comprehensive understanding through refined animal models. This study advances knowledge of TBD and highlights the importance of exploring co-infection dynamics in host-pathogen interactions.


Assuntos
Coinfecção , Modelos Animais de Doenças , Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Doença de Lyme , Camundongos Endogâmicos C3H , Animais , Coinfecção/microbiologia , Coinfecção/virologia , Camundongos , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Doença de Lyme/microbiologia , Encefalite Transmitida por Carrapatos/virologia , Grupo Borrelia Burgdorferi , Feminino
15.
Pathogens ; 13(6)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38921747

RESUMO

Ixodes ricinus ticks are vectors of a plethora of pathogens. The purpose of this study was to screen 398 I. ricinus ticks for a variety of pathogens. Following the pooling, homogenization, and extraction of total nucleic acids, a real-time PCR was applied for the detection of a panel of tick-borne pathogens, while additional conventional PCRs combined with Sanger sequencing were applied for the detection of viruses and typing of Rickettsia and Borrelia species. At least one pathogen was detected in 60 of the 80 (75%) tick pools. Rickettsia spp. predominated, as it was detected in 63.75% of the pools (51/80; MIR 12.81%), followed by Borrelia spp. (35 pools (45%); MIR 8.79%), while Anaplasma phagocytophilum was detected in 2 pools (2.5%, MIR 0.5%). The ticks of six Rickettsia-positive pools were tested individually (from stored half-ticks); all sequences were identical to those of R. monacensis. Similarly, the ticks of six Borrelia-positive pools were tested individually, and it was shown that four belonged to the genospecies Borrelia garinii and two to Borrelia valaisiana. Phleboviruses were detected in 3 pools (3.75%; MIR 0.75%), with sequences clustering in the Ixovirus genus, while nairoviruses were detected in 7 pools (8.75%; MIR 1.76%), with one sequence clustering in the Orthonairovirus genus, and six clustering in the Norwavirus genus. Although a small number of ticks from only one area in Greece were tested, a variety of pathogens together with recently identified viruses were detected, prompting further studies in ticks and surveillance studies in humans.

16.
Cureus ; 16(5): e59687, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38836151

RESUMO

Antibiotics are among the most common causes of drug-induced liver injury worldwide. Amoxicillin/clavulanic acid and nitrofurantoin are the most common culprits while tetracyclines are a rare cause of liver injury. Among tetracyclines, minocycline has been reported more frequently than doxycycline, which is an extremely rare cause of drug-induced liver injury. We present a healthy 28-year-old male patient from rural United States who was taking doxycycline for Lyme disease. After five days of therapy, he developed nausea, vomiting, fatigue, and significant transaminitis consistent with a hepatocellular pattern of liver injury. After a thorough workup which ruled out other causes such as infection, autoimmune diseases, liver malignancy, and vascular, structural, and metabolic disorders, his liver injury was attributed to doxycycline. We reached the diagnosis also by demonstrating a consistent temporal association between doxycycline intake and liver injury and the patient recovered completely with the cessation of doxycycline. Recognition of doxycycline as a cause of drug-induced liver injury should be considered in patients utilizing this antibiotic. Doxycycline, unlike minocycline, has a short latency period. Early recognition and discontinuation of doxycycline in our patient resulted in the complete resolution of symptoms and transaminitis preventing further morbidity and mortality.

17.
One Health ; 18: 100764, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855195

RESUMO

Vector-borne diseases (VBDs) are considered as (re-)emerging, but information on the transmission cycles and wildlife reservoirs is often incomplete, particularly with regard to urban areas. The present study investigated blood samples from European hedgehogs (Erinaceus europaeus) presented at wildlife rehabilitation centres in the region of Hanover. Past exposure to B. burgdorferi sensu lato (s.l.) and tick-borne encephalitis virus (TBEV) was assessed by serological detection of antibodies, while current infections with Borrelia spp., Anaplasma phagocytophilum, Rickettsia spp., Neoehrlichia mikurensis, Bartonella spp., Babesia spp. and Spiroplasma ixodetis were investigated by (q)PCR. Of 539 hedgehogs tested for anti-Borrelia antibodies, 84.8% (457/539) were seropositive, with a higher seropositivity rate in adult than subadult animals, while anti-TBEV antibodies were detected in one animal only (0.2%; 1/526). By qPCR, 31.2% (168/539) of hedgehog blood samples were positive for Borrelia spp., 49.7% (261/525) for A. phagocytophilum, 13.0% (68/525) for Bartonella spp., 8.2% for S. ixodetis (43/525), 8.0% (42/525) for Rickettsia spp. and 1.3% (7/525) for Babesia spp., while N. mikurensis was not detected. While further differentiation of Borrelia spp. infections was not successful, 63.2% of the A. phagocytophilum infections were assigned to the zoonotic ecotype I and among Rickettsia spp. infections, 50.0% to R. helvetica by ecotype- or species-specific qPCR, respectively. Sequencing revealed the presence of a Rickettsia sp. closely related to Rickettsia felis in addition to a Bartonella sp. previously described from hedgehogs, as well as Babesia microti and Babesia venatorum. These findings show that hedgehogs from rehabilitation centres are valuable sources to identify One Health pathogens in urban areas. The hedgehogs are not only exposed to pathogens from fleas and ticks in urban areas, but they also act as potent amplifiers for these vectors and their pathogens, relevant for citizens and their pets.

18.
Microbiol Res ; 286: 127790, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38851009

RESUMO

Understanding the intricate ecological interactions within the microbiome of arthropod vectors is crucial for elucidating disease transmission dynamics and developing effective control strategies. In this study, we investigated the ecological roles of Coxiella-like endosymbiont (CLE) and Anaplasma marginale across larval, nymphal, and adult stages of Rhipicephalus microplus. We hypothesized that CLE would show a stable, nested pattern reflecting co-evolution with the tick host, while A. marginale would exhibit a more dynamic, non-nested pattern influenced by environmental factors and host immune responses. Our findings revealed a stable, nested pattern characteristic of co-evolutionary mutualism for CLE, occurring in all developmental stages of the tick. Conversely, A. marginale exhibited variable occurrence but exerted significant influence on microbial community structure, challenging our initial hypotheses of its non-nested dynamics. Furthermore, in silico removal of both microbes from the co-occurrence networks altered network topology, underscoring their central roles in the R. microplus microbiome. Notably, competitive interactions between CLE and A. marginale were observed in nymphal network, potentially reflecting the impact of CLE on the pathogen transstadial-transmission. These findings shed light on the complex ecological dynamics within tick microbiomes and have implications for disease management strategies.


Assuntos
Anaplasma marginale , Coxiella , Larva , Rhipicephalus , Simbiose , Animais , Rhipicephalus/microbiologia , Coxiella/genética , Larva/microbiologia , Larva/crescimento & desenvolvimento , Microbiota , Ninfa/microbiologia , Ninfa/crescimento & desenvolvimento
19.
Exp Appl Acarol ; 93(1): 49-69, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38869724

RESUMO

Ixodes ricinus is a vector of several pathogens of public health interest. While forests are the primary habitat for I. ricinus, its abundance and infection prevalence are expected to vary within forest stands. This study assesses the spatio-temporal variations in tick abundance and infection prevalence with three pathogens in and around a peri-urban forest where human exposure is high. Ticks were sampled multiple times in 2016 and 2018 in multiple locations with a diversity of undergrowth, using the consecutive drags method. Three zoonotic pathogens were screened for, Borrelia burgdorferi s.l., Coxiella burnetii, and Francisella tularensis. The influence of season, type of site and micro-environmental factors on tick abundance were assessed with negative binomial generalized linear mixed-effects models. We collected 1642 nymphs and 181 adult ticks. Ticks were most abundant in the spring, in warmer temperatures, and where undergrowth was higher. Sites with vegetation unaffected by human presence had higher abundance of ticks. Forest undergrowth type and height were significant predictors of the level of tick abundance in a forest. The consecutive drags method is expected to provide more precise estimates of tick abundance, presumably through more varied contacts with foliage. Borrelia burgdorferi s.l. prevalence was estimated from pooled ticks at 5.33%, C. burnetii was detected in six pools and F. tularensis was not detected. Borrelia afzelii was the dominant B. burgdorferi genospecies. Tick abundance and B. burgdorferi s.l. infection prevalence were lower than other estimates in Belgian forests.


Assuntos
Coxiella burnetii , Florestas , Francisella tularensis , Ixodes , Animais , Bélgica/epidemiologia , Ixodes/microbiologia , Ixodes/crescimento & desenvolvimento , Francisella tularensis/isolamento & purificação , Coxiella burnetii/isolamento & purificação , Coxiella burnetii/fisiologia , Ninfa/microbiologia , Ninfa/crescimento & desenvolvimento , Borrelia burgdorferi/isolamento & purificação , Borrelia burgdorferi/fisiologia , Estações do Ano , Densidade Demográfica , Feminino
20.
Acta Trop ; 256: 107244, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762942

RESUMO

Questing ticks carry various tick-borne pathogens (TBPs) that are responsible for causing tick-borne diseases (TBDs) in humans and animals around the globe, especially in the tropics and sub-tropics. Information on the distribution of ticks and TBPs in a specific geography is crucial for the formulation of mitigation measures against TBDs. Therefore, this study aimed to survey the TBPs in the questing tick population in Bangladesh. A total of 2748 questing hard ticks were collected from the pastures in Sylhet, Bandarban, Sirajganj, Dhaka, and Mymensingh districts through the flagging method. After morphological identification, the ticks were grouped into 142 pools based on their species, sexes, life stages, and collection sites. The genomic DNA extracted from tick specimens was screened for 14 pathogens, namely Babesia bigemina (AMA-1), Babesia bovis (RAP-1), Babesia naoakii (AMA-1), Babesia ovis (18S rRNA), Theileria luwenshuni (18S rRNA), Theileria annulata (Tams-1), Theileria orientalis (MPSP), Anaplasma marginale (groEL), Anaplasma phagocytophilum (16S rRNA), Anaplasma bovis (16S rRNA), Anaplasma platys (16S rRNA), Ehrlichia spp. (16S rRNA), Rickettsia spp. (gltA), and Borrelia (Bo.) spp. (flagellin B) using genus and species-specific polymerase chain reaction (PCR) assays. The prevalence of the detected pathogens was calculated using the maximum likelihood method (MLE) with 95 % confidence interval (CI). Among 2748 ixodid ticks, 2332 (84.86 %) and 416 (15.14 %) were identified as Haemaphysalis bispinosa and Rhipicephalus microplus, respectively. Haemaphysalis bispinosa was found to carry all the seven detected pathogens, while larvae of R. microplus were found to carry only Bo. theileri. Among the TBPs, the highest detection rate was observed in A. bovis (20/142 pools, 0.81 %, CI: 0.51-1.20), followed by T. orientalis (19/142 pools, 0.72 %, CI: 0.44-1.09), T. luwenshuni (9/142 pools, 0.34 %, CI: 0.16-0.62), B. ovis (4/142 pools, 0.15 %, CI: 0.05 - 0.34) and Bo. theileri (4/142 pools, 0.15 %, CI: 0.05-0.34), Ehrlichia ewingii (3/142 pools, 0.11 %, CI: 0.03-0.29), and Babesia bigemina (1/142, 0.04 %, CI: 0.00 - 0.16). This study reports the existence of T. luwenshuni, E. ewingii, and Bo. theileri in Bangladesh for the first time. The novel findings of this study are the foremost documentation of transovarian transmission of B. bigemina and E. ewingii in H. bispinosa and also provide primary molecular evidence on the presence of E. ewingii and Bo. theileri in H. bispinosa. Therefore, this study may shed light on the circulating TBPs in ticks in the natural environment and thereby advocate awareness among physicians and veterinarians to control and prevent TBDs in Bangladesh.


Assuntos
Babesia , Doenças Transmitidas por Carrapatos , Animais , Bangladesh/epidemiologia , Babesia/isolamento & purificação , Babesia/genética , Feminino , Masculino , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Theileria/isolamento & purificação , Theileria/genética , Theileria/classificação , Ixodidae/microbiologia , Ixodidae/parasitologia , Anaplasma/isolamento & purificação , Anaplasma/genética , Ehrlichia/isolamento & purificação , Ehrlichia/genética , Carrapatos/microbiologia , Carrapatos/parasitologia , DNA Bacteriano/genética , Humanos
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