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1.
Artículo en Inglés | MEDLINE | ID: mdl-39483631

RESUMEN

This literature-based review aims to distinguish studies describing co-infection with tick-borne pathogens from those describing co-detection or co-exposure scenarios. The review analyzed 426 papers and identified only 20 with direct evidence of co-infection in humans and animals, highlighting the need for accurate terminology and proposing definitions for co-infection, co-exposure and co-detection. Current diagnostic methods - including serology and molecular techniques - have limitations in accurately identifying real co-infections, often leading to misinterpretation. The review highlights the importance of developing laboratory models to better understand tick-borne pathogen interactions, and advocates improved diagnostic strategies for tick screening by testing their RNA for co-infections. Moreover, the establishment of additional animal models for pathogen co-infection will help develop our understanding of selection pressures for various traits of tick-borne pathogens (such as virulence and transmissibility) over time. This comprehensive analysis provides insights into the complexity of tick-borne pathogen co-infections and calls for precise diagnostic terms to improve the clarity and effectiveness of future research.

3.
Ticks Tick Borne Dis ; 15(6): 102402, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39368217

RESUMEN

Ixodes ricinus is the most important tick vector in central and western Europe and one of the most researched parasites. However, in the published literature on the tick and the pathogens it transmits, conjecture about specific transmission cycles and the clinical significance of certain microbes is not always clearly separated from confirmed facts. This article aims to present up-to-date, evidence-based information about the well-researched human pathogens tick-borne encephalitis virus, louping-ill virus, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and several Babesia species, with a focus on their development in the tick, transmission dynamics and the competent reservoir hosts that support their circulation in the environment. Borrelia miyamotoi, Neoehrlichia mikurensis, Rickettsia helvetica and Rickettsia monacensis, which are much less common causes of disease but may affect immunocompromised patients, are also briefly discussed. Finally, the possible role of I. ricinus in the transmission of Coxiella burnetii, Francisella tularensis, Bartonella spp. and Spiroplasma ixodetis is reviewed.

4.
Adv Parasitol ; 126: 229-251, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39448192

RESUMEN

Hard ticks (family Ixodidae) are significant vectors of pathogens affecting humans and animals. This review explores the composition of tick saliva, focusing on proteases and protease inhibitors, their biological roles, and their potential in vaccines and therapies. Tick saliva contains various proteases, mostly metalloproteases, serpins, cystatins, and Kunitz-type inhibitors, which modulate host hemostatic, immune, and wound healing responses to facilitate blood feeding and pathogen transmission. Proteases inhibit blood clotting, degrade extracellular matrix components, and modulate immune responses. Serpins, cystatins, and Kunitz-type inhibitors further inhibit key proteases involved in coagulation and inflammation, making them promising candidates for anticoagulant, anti-inflammatory, and immunomodulatory therapies. Several tick proteases and protease inhibitors have shown potential as vaccine targets, reducing tick feeding success and pathogen transmission. Future research should focus on comprehensive proteomic and genomic analyses, detailed structural and functional studies, and vaccine trials. Advanced omics approaches and bioinformatics tools will be crucial in uncovering the complex interactions between ticks, hosts, and pathogens, improving tick control strategies and public health outcomes.


Asunto(s)
Ixodidae , Péptido Hidrolasas , Inhibidores de Proteasas , Saliva , Animales , Inhibidores de Proteasas/farmacología , Saliva/química , Péptido Hidrolasas/metabolismo , Ixodidae/fisiología , Ixodidae/enzimología , Humanos
5.
Artículo en Inglés | MEDLINE | ID: mdl-39399650

RESUMEN

Spatio-temporal scales have a clear influence on microbial community distribution and diversity and should thus be applied to study the dynamics of microorganisms. The invasive tick species Hyalomma marginatum has recently become established in southern France. It may carry pathogens of medical and veterinary interest including the Crimean-Congo haemorrhagic fever virus, Rickettsia aeschlimannii, Theileria equi and Anaplasma phagocytophilum. Pathogenic communities of H. marginatum have been identified and their spatial distribution characterized, but their temporal dynamics remain unknown. Hyalomma marginatum ticks were collected from hosts at monthly intervals from February to September 2022 in a site in southern France to study their presence and temporal dynamics. Of the 281 ticks analysed, we detected pathogens including R. aeschlimannii, Anaplasma spp. and T. equi with infection rates reaching 47.0%, 4.6% and 11.0%, respectively. A total of 14.6% of ticks were infected with at least Theileria or Anaplasma, with monthly fluctuations ranging from 2.9% to 28.6%. Strong temporal patterns were observed for each pathogen detected, particularly for R. aeschlimannii, whose infection rates increased dramatically at the beginning of summer, correlated with monthly mean temperatures at the site. Based on these results, we hypothesise that R. aeschlimannii may be a secondary symbiont of H. marginatum and could be involved in the stress response to temperature increase and mediate thermal tolerance of H. marginatum. Analysis of monthly and seasonal fluctuations in pathogens transmitted by H. marginatum led us to conclude that the risk of infection is low but persists throughout the period of H. marginatum activity, with a notable increase in summer.

6.
Ticks Tick Borne Dis ; 15(6): 102405, 2024 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-39427603

RESUMEN

Tick-borne pathogens in the genus Rickettsia are the causative agents of severe and potentially fatal spotted fever group (SFG) and typhus group diseases in dogs and humans. Climate, habitat, and land-use changes are impacting vector ranges, with expansions potentially resulting in novel pathogens being introduced into naïve locations. Despite the public health importance of SFG Rickettsia, there are relatively few data on the prevalence and diversity of rickettsial pathogens in sub-Saharan Africa. The aim of this study was to characterize the SFG Rickettsia prevalence and diversity in ixodid ticks (104 Amblyomma spp., 160 Rhipicephalus spp., and one Hyalomma truncatum) collected from domestic dogs in Chad, Africa. Ticks were screened for Rickettsia spp. using a nested PCR targeting the 17-kDa gene. Species identification was through bidirectional Sanger sequencing of the 17-kDa, ompA, ompB, and/or gltA gene targets. A total of 43.3 % (115/265) ticks were positive for Rickettsia spp. and six Rickettsia species were identified: R. africae, R. massiliae, R. conorii, R. felis, R. monacensis and Candidatus Rickettsia muridii. Seven additional samples were positive for Rickettsia of undetermined species. Rickettsia africae, an important zoonotic pathogen, was found in 81 % (79/97) of A. variegatum and 29 % (2/7) of an A. marmoreum complex species, a group that infests a wide range of birds and mammals, including humans. Finally, we detected a high diversity of Rickettsia spp., most of which were zoonotic, in Rh. muhsamae. Collectively these data indicate there is a risk of rickettsiosis in Chad and further studies on ticks and rickettsial pathogens in this region are warranted.

7.
Artículo en Inglés | MEDLINE | ID: mdl-39291322

RESUMEN

Background: Infection with tick-borne pathogens (TBPs) causes anemia, jaundice, and growth retardation in cattle. Many studies have conducted antigen (Ag) tests for major TBPs, such as Anaplasma spp. and Theileria spp., in Korean indigenous cattle (KIC); however, few studies have analyzed antibodies (Ab) against these pathogens. Materials and Methods: This study simultaneously tested 15 housed cattle raised indoor for over a year and 67 grazing cattle for Anaplasma spp. and Theileria spp. Ag using polymerase chain reaction analysis and Ab using enzyme-linked immunosorbent assay. Results: The A. phagocytophilum was detected in 3 housed cattle (20.0%) and 30 grazing cattle (44.8%), whereas the T. orientalis was detected in 3 housed cattle (20.0%) and 54 grazing cattle (80.6%). The positivity rates for Anaplasma spp. Ab did not differ significantly between housed and grazing cattle (4 out of 15 [93.3%] and 55 out of 67 [80.0%], respectively). The positivity rates for Theileria spp. Ab were higher in grazing cattle than in housed cattle (21 of 67 [31.3%] and 0 out of 15 [0.0%], respectively) (P < 0.01). No difference was observed between the frequency of grazing and the abundance of Ab against either pathogen. Meanwhile, as a result of comparing the detection of pathogen Ag and Ab, Anaplasma spp. showed the highest proportions of 73.3% and 47.8% in Ag (-)/Ab (+) for housed cattle and grazing cattle, respectively. Theileria spp. showed the highest rates of 80.0% in Ag (-)/Ab (-) for housed cattle and 52.2% in Ag (+)/Ab (-) for grazing cattle. Conclusions: This is the first study to determine the impact of antibody abundance against Anaplasma spp. and Theileria spp. on antigen prevalence in KIC.

8.
IJID Reg ; 12: 100414, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39257853

RESUMEN

Objectives: Borrelia burgdorferi sensu lato (Bbsl) and tick-borne encephalitis virus (TBEV) are tick-borne pathogens. This study aimed to investigate the seroprevalence of these pathogens in Danish blood donors. Methods: A total of 1000 plasma samples equally distributed (n = 200) from all five Danish regions were analyzed. Commercially available enzyme-linked immunosorbent assays were used to screen the samples for immunoglobulin G antibodies against Bbsl and TBEV. The samples positive for antibodies against TBEV were further examined with a commercially available enzyme-linked immunosorbent assay and a Luminex-based TBEV suspension multiplex immunoassay for specific antibodies against non-structural protein 1 (NS1) antigen suggestive of previous infection. Results: A total of 62 samples tested positive for immunoglobulin G antibodies against Bbsl. A total of 40 samples were positive or borderline for antibodies against TBEV, indicating potential infection or vaccination. Of these, one had antibodies against NS1, indicating past infection. The seroprevalence of Bbsl was 6.2% (95% confidence interval 4.8-7.8), with equal seroprevalence in all five regions. The seroprevalence of TBEV was 0.1% (95% confidence interval 0.01-0.62%). Conclusions: The seroprevalence of Bbsl was similar throughout the country and corresponds well with previous studies. The seroprevalence of TBEV NS1 was low, which is in line with a low number of reported tick-borne encephalitis cases in Denmark. The NS1 positive sample was from the Capital Region, an endemic TBEV area.

9.
Artículo en Inglés | MEDLINE | ID: mdl-39258000

RESUMEN

Ticks are important ectoparasites of domestic animals, wild animals and humans. They spread a variety of infective agents such as protozoans, viruses, and bacteria. Cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens due to the type of production system practiced by the farmers. Hence, this review was focused on the occurrence of ticks and tick-borne pathogens in cattle reared by smallholder farmers in South Africa. The systematic search produced a total of 13,408 articles from four databases, and after screening processes, the review utilized 23 articles published between 1983 and 2023. A total of 26 tick species belonging to seven genera were identified in the reviewed articles, with Rhipicephalus (Boophilus) decoloratus and Rhipicephalus evertsi evertsi being the most frequently reported tick species in South Africa followed by Amblyomma hebreum, Rhipicephalus appendiculatus, Hyalomma marginatum rufipes, Rhipicephalus microplus, Rhipicephalus follis, Rhipicephalus gertrudae and Hyalomma truncatum. The most frequently reported tick-borne pathogens across the provinces included Babesia bigemina, Babesia bovis, and Anaplasma marginale, with Eastern Cape Province accounting for most of the records followed by KwaZulu-Natal and Mpumalanga Provinces. The findings of this review confirm that cattle reared by smallholder farmers harbour various ticks and tick-borne pathogens of veterinary, public health and economic importance, and regular monitoring of tick infestations in South Africa is recommended to avoid disease outbreaks.

10.
Ann Agric Environ Med ; 31(3): 345-350, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39344722

RESUMEN

INTRODUCTION AND OBJECTIVE: Ticks (Acari:Ixodida) are dangerous ectoparasites and, at the same time, vectors and/or resevoirs of many pathogens, among others Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Babesia microti. These ethiological agents of Lyme borreliosis, anaplasmosis and babesiosis are transferred to humans mainly by ticks during feeding. The aim of this study was to estimate the potential risk of human exposure to tick borne infection of B. burgdorferi s.l., A. phagocytophilum and B. microti in selected areas of Poprad Landscape Park in southern Poland [PLP]. MATERIAL AND METHODS: Ixodes ricinus ticks were collected from vegetation by the flagging method. Under a stereoscopic microscope, specimens were determined to the species and developmental stage. In total, DNA was isolated from 363 ticks. To detect B. burgdorferi s.l,.two pairs of primers specific to the flagelline gene were used. In turn, to detect A. phagocytophilum and B. microti, two pairs of primers specific to the 16S rRNA gene fragment and 18S rRNA gene fragment were used, respectively. The amplification products were separated electrophoretically in 2% ethidium bromide stained agarose gels, and visualized under ultra violet light. RESULTS: Generally, pathogens were observed in 19.6% of ticks. Borrelia burgdorferi sensu lato was detected in 11.8% of studied ticks. In turn, A. phagocytophlium and B. microti were presented, respectively, in 0.3% and 7.4% of examined I. ricinus. CONCLUSIONS: The study indicated a potentially high risk of human exposure to infection with tick-borne pathogens, mainly B. burgdorferi s.l. and B. microti, in the areas of PLP. In turn, the presence of A. phagocytophilum in lower percentage was shown in the studied ticks.


Asunto(s)
Anaplasma phagocytophilum , Babesia microti , Grupo Borrelia Burgdorferi , Ixodes , Parques Recreativos , Polonia , Anaplasma phagocytophilum/aislamiento & purificación , Anaplasma phagocytophilum/genética , Babesia microti/aislamiento & purificación , Babesia microti/genética , Animales , Humanos , Ixodes/microbiología , Ixodes/parasitología , Ixodes/crecimiento & desarrollo , Grupo Borrelia Burgdorferi/aislamiento & purificación , Grupo Borrelia Burgdorferi/genética , Enfermedades por Picaduras de Garrapatas/parasitología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedad de Lyme/microbiología , Enfermedad de Lyme/epidemiología , Babesiosis/parasitología , Babesiosis/epidemiología , Babesiosis/transmisión , Femenino , Masculino , Ninfa/microbiología , Ninfa/crecimiento & desarrollo , Ninfa/parasitología
11.
Acta Trop ; 260: 107412, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39332755

RESUMEN

In Mongolia, a substantial segment of the population is engaged in pastoralism, leading to frequent interactions with livestock and heightened exposure to tick-infested environments. Consequently, ticks and the endemic tick-borne pathogens (TBPs) they harbor present significant health threats. In May 2021, we conducted a study to evaluate the prevalence of 9 TBPs in ticks collected from four regions in Mongolia: Uvurkhangai, Tuv, Bayan-Ulgii, and Khentii. The pathogens surveyed included Anaplasma, Rickettsia, Bartonella, Borrelia, Ehrlichia, Babesia, Toxoplasma, Theileria, and lumpy skin disease virus. Molecular analysis of 1142 ticks revealed that, although the majority of TBPs were not detected, 89.1 % of the ticks were positive for Rickettsia. Genetic characterization using the 16S rRNA and gltA genes identified the pathogen identified the pathogen Rickettsia raoultii. Species identification indicated a predominance of Dermacentor nuttalli (70.0 %) and Dermacentor silvarum (30.0 %). These findings highlight the extensive prevalence of R. raoultii in Mongolia and underscore the urgent need for heightened awareness and preventive measures due to the high level of interaction between livestock and humans. The genetic similarity of R. raoultii sequences to those found in neighboring countries suggests potential cross-border transmission, underscoring the importance of conducting similar research in surrounding regions. This study advances our understanding of the epidemiology of tick-borne diseases in Mongolia and can inform public health strategies aimed at mitigating the risks associated with these infections.

12.
Sci Rep ; 14(1): 22129, 2024 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333333

RESUMEN

Tick-borne bacteria of the genera Rickettsia and Coxiella cause several emerging veterinary and human infectious diseases. Ticks of the genus Hyalomma are medically important vectors due to their potential role in the transmission of pathogens to vertebrate hosts. There is an inadequate knowledge on tick-borne Rickettsia spp. and Coxiella spp. in ticks infesting transhumant camels in Pakistan. In this study, we conducted a molecular survey for screening of Rickettsia spp. and Coxiella spp. in ticks infesting camels. Seven hard tick species including Hyalomma dromedarii, Hyalomma anatolicum, Hyalomma scupense, Hyalomma isaaci, Hyalomma turanicum, Hyalomma asiaticum, and Rhipicephalus sanguineus s.l were confirmed on camels in three distinct physiographic regions of Khyber Pakhtunkhwa, Pakistan. A subset of morphologically identified ticks were subjected to molecular assays for the genetic characterization of ticks and the detection and genetic characterization of Rickettsia and Coxiella species using standard genetic markers. Ticks screened for pathogens resulted in the detection of Rickettsia aeschlimannii and Candidatus Rickettsia shennongii and Coxiella burnetii. The molecular analysis further reveals the presences of an undetermined Rickettsia aeschlimannii-like species, that is making a distinct phylogenetic clade with R. aeschlimannii. The detection of pathogens in camel ticks poses potential health hazards as these ticks frequently bites humans. Molecular screening of Rickettsia spp. and Coxiella spp. associated with camel ticks is a preliminary step toward the surveillance of evaluating their zoonotic threats in the region.


Asunto(s)
Camelus , Coxiella burnetii , Rickettsia , Animales , Camelus/microbiología , Camelus/parasitología , Rickettsia/genética , Rickettsia/aislamiento & purificación , Rickettsia/clasificación , Coxiella burnetii/genética , Coxiella burnetii/aislamiento & purificación , Pakistán , Filogenia , Garrapatas/microbiología , Ixodidae/microbiología , Infecciones por Rickettsia/microbiología , Infecciones por Rickettsia/transmisión , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/parasitología
13.
Vet Parasitol Reg Stud Reports ; 55: 101105, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39326961

RESUMEN

Ticks are arachnid blood-feeding parasites, which infest livestock, wildlife, and humans, transmitting medically and veterinary significant pathogens. Their biodiversity and distribution in wild animals remains complex. This study analysed archived tick samples (n = 48) from the South African Biodiversity Institute (SANBI) Wildlife Biobank utilizing morphology and genetic analyses of the 16S rRNA and COI (DNA barcoding) mitochondrial genes to identify ticks collected among 13 vertebratesavian, reptilian, and mammalian host species. The specimens came from nine localities including nature reserves and captive facilities (zoological garden) in South Africa, Namibia, and Botswana. These ticks were also assessed for associated pathogens with the reverse line blot (RLB) hybridization assay. Seven tick genera, Amblyomma, Hyalomma, Haemaphysalis, Ixodes, Rhipicephalus, Rhipicentor, and Otobius were identified, with Amblyomma being the most prevalent (22.9 %) in our sample set. Obtained sequences were 95-100 % similar to published records of tick species collected from wild and domestic animals, as well as those collected from vegetation, from different southern African areas. However, tick specimens (n = 3) identified morphologically as Hyalomma truncatum, Rhipicephalus e. evertsi, and R. simus, were, on a molecularly level, more closely related to their sister taxa (H. glabrum, R. e. mimeticus, and R. gertrudae, respectively) suggesting a need for taxonomic verification. With the RLB hybridization assay, six samples reacted with the Ehrlichia/Anaplasma genus-specific probe, while two reacted with the Theileria/Babesia genus-specific probe. Sequencing of the RLB amplicons targeting the 18S rRNA gene (n = 2) indicated 100 % similarity to Hepatozoon fitzsimonsi, while one was closely related to He. ingwe with 99.39 % similarity. The results show that wildlife harbour different tick species, and pathogen detection identified novel genotypes, indicating wildlife as potential pathogens reservoirs. This study enhances our understanding of tick biodiversity, distribution and highlights wildlife's role in harbouring diverse tick species and novel pathogens.


Asunto(s)
Animales Salvajes , ARN Ribosómico 16S , Infestaciones por Garrapatas , Enfermedades por Picaduras de Garrapatas , Garrapatas , Animales , Sudáfrica/epidemiología , Animales Salvajes/parasitología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/veterinaria , Enfermedades por Picaduras de Garrapatas/parasitología , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , ARN Ribosómico 16S/análisis , Garrapatas/parasitología , Garrapatas/microbiología , Filogenia , Femenino , Código de Barras del ADN Taxonómico/veterinaria , Animales de Zoológico/parasitología
14.
Ticks Tick Borne Dis ; 16(1): 102399, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39321670

RESUMEN

The islands of Brittany provide unique ecosystems for ticks and tick-borne diseases owing to their oceanic climate, influencing interactions among ticks, hosts, and pathogens. We conducted a preliminary investigation on Belle-Île-en-Mer, an island off the Atlantic coast of Brittany in western France, to assess the prevalence of questing adult ticks and associated human pathogenic bacteria. Dermacentor spp. were found to dominate the tick population (61 %): 23 % Dermacentor reticulatus and 77 % D. marginatus. Haemaphysalis punctata (27 %) was also prevalent on the island, and Ixodes ricinus (12 %) was detected for the first time on Belle-Île-en-Mer. Both Dermacentor species harbored either Rickettsia slovaca (24 %) or Rickettsia raoultii (20 %), whereas I. ricinus carried Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum but not Borrelia miyamotoi or Neoehrlichia mikurensis. Detection of two potentially pathogenic species in the B. burgdorferi sensu lato complex, B. afzelii and B. lusitaniae, along with A. phagocytophilum underscores the current risk of Lyme borreliosis and anaplasmosis. The high prevalence of Rickettsia infection in Dermacentor indicates an additional risk of human rickettsioses.

15.
J Vet Res ; 68(3): 355-361, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39318522

RESUMEN

Introduction: Ticks are obligate blood-feeding arthropods that cause significant economic losses in domestic animal husbandry and threaten public health. However, information about soft ticks (Acari: Argasidae) and tick-borne pathogens in the Xinjiang Uygur Autonomous Region (XUAR) of China is scarce. Material and Methods: In this study, PCR assays and gene sequencing were used to detect and analyse the epidemiological features of Anaplasma ovis, Theileria ovis and Brucella abortus parasitic infections in 366 Ornithodoros lahorensis soft ticks collected from five sampling sites in the XUAR from October 2019 to March 2022. The ticks were identified by morphological and molecular methods as O. lahorensis. The PCR was conducted using primers complementary to the major surface protein 4 (Msp4) gene of A. ovis, the 18S ribosomal RNA (18S rRNA) of T. ovis and the outer membrane protein 22 (Omp22) gene of B. abortus. Results: The overall infection rate was 91/366 (24.9%) for A. ovis, 127/366 (34.7%) for T. ovis and 94/366 (25.6%) for B. abortus. Sequencing analysis indicated that A. ovis Msp4, T. ovis 18S rRNA and B. abortus Omp22 genes from XUAR isolates showed 99.58-100% identity with documented isolates from other countries. Conclusion: This study provides fundamental evidence for the occurrence of A. ovis, T. ovis and B. abortus in O. lahorensis. Therefore, the potential threat of soft ticks to livestock and humans should not be ignored. This study expands the understanding of the existence of tick-borne pathogens in O. lahorensis and is expected to improve the strategies for prevention and control of ticks and tick-borne diseases in China.

16.
Vet Res Commun ; 48(5): 3197-3207, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39145855

RESUMEN

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.


Asunto(s)
Camelus , Reservorios de Enfermedades , Ixodidae , Animales , Camelus/parasitología , Reservorios de Enfermedades/veterinaria , Reservorios de Enfermedades/microbiología , Ixodidae/microbiología , Enfermedades por Picaduras de Garrapatas/veterinaria , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/parasitología , Roedores/parasitología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Egipto/epidemiología , Femenino
17.
Infect Immun ; 92(10): e0021424, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39120148

RESUMEN

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.


Asunto(s)
Proteínas Bacterianas , Borrelia burgdorferi , Regulación Bacteriana de la Expresión Génica , Enfermedad de Lyme , Borrelia burgdorferi/genética , Animales , Ratones , Enfermedad de Lyme/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Plásmidos/genética , Factor sigma/genética , Factor sigma/metabolismo , Ratones Endogámicos C3H
18.
Parasit Vectors ; 17(1): 361, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39182156

RESUMEN

BACKGROUND: European wildcats (Felis silvestris) are widely distributed in Europe and a strictly protected species in Germany. Lately, anthropogenic protective efforts lead to increasing numbers of wildcats in southwestern Germany. Moreover, in recent years the numbers of domestic cats are increasing. Thus, the contact between domestic and wildcats may lead to the spread of zoonotic pathogens in both animal species. As data on vector-borne pathogens (VBPs) in wildcats from Germany are limited to date, the objective of this study was to investigate the presence and current distribution of VBPs in wildcats from southwestern Germany. METHODS: Skin and spleen samples from 117 European wildcats, originating from a regional carcass-monitoring program in southwestern Germany, were examined by real-time and conventional polymerase chain reaction (PCR) for the presence of Anaplasma phagocytophilum, Neoehrlichia mikurensis, Rickettsia spp., Bartonella spp., and Piroplasmida. RESULTS: In total, 6.8% (n = 8) of the wildcats were Rickettsia-positive, specified as R. helvetica. Three wildcats were positive for A. phagocytophilum (2.6%), one for Bartonella spp., namely B. taylorii (0.8%), and 84 for Cytauxzoon spp. (71.8%). Out of these 84 samples, 23 were further sequenced revealing very high identity levels (99.84-100%) to C. europaeus, which is considered to be pathogenic for domestic cats. All wildcats were negative for the presence of N. mikurensis DNA. CONCLUSIONS: European wildcats in southwestern Germany are hosting several VBPs. With the exception of Cytauxzoon spp., low prevalence rates of most examined pathogens suggest that wildcats are primarily incidental hosts for sylvatic pathogens associated with rodents, in contrast to domestic cats. However, the high prevalence of the cat-associated pathogen C. europaeus suggests that wildcats in southwestern Germany may serve as reservoirs for this pathogen.


Asunto(s)
Animales Salvajes , Felis , Animales , Alemania/epidemiología , Animales Salvajes/parasitología , Animales Salvajes/microbiología , Felis/parasitología , Felis/microbiología , Infecciones Protozoarias en Animales/epidemiología , Infecciones Protozoarias en Animales/parasitología , Gatos , Piroplasmida/genética , Piroplasmida/aislamiento & purificación , Enfermedades Transmitidas por Vectores/epidemiología , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/parasitología , Bartonella/aislamiento & purificación , Bartonella/genética , Bartonella/clasificación , Rickettsia/aislamiento & purificación , Rickettsia/genética , Rickettsia/clasificación
19.
PeerJ ; 12: e17944, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193518

RESUMEN

Environmental dimensions, such as temperature, precipitation, humidity, and vegetation type, influence the activity, survival, and geographic distribution of tick species. Ticks are vectors of various pathogens that cause disease in humans, and Ixodes scapularis and Amblyomma americanum are among the tick species that transmit pathogens to humans across the central and eastern United States. Although their potential geographic distributions have been assessed broadly via ecological niche modeling, no comprehensive study has compared ecological niche signals between ticks and tick-borne pathogens. We took advantage of National Ecological Observatory Network (NEON) data for these two tick species and associated bacteria pathogens across North America. We used two novel statistical tests that consider sampling and absence data explicitly to perform these explorations: a univariate analysis based on randomization and resampling, and a permutational multivariate analysis of variance. Based on univariate analyses, in Amblyomma americanum, three pathogens (Borrelia lonestari, Ehrlichia chaffeensis, and E. ewingii) were tested; pathogens showed nonrandom distribution in at least one environmental dimension. Based on the PERMANOVA test, the null hypothesis that the environmental position and variation of pathogen-positive samples are equivalent to those of A. americanum could not be rejected for any of the pathogens, except for the pathogen E. ewingii in maximum and minimum vapor pressure and minimum temperature. For Ixodes scapularis, six pathogens (A. phagocytophilum, Babesia microti, Borrelia burgdorferi sensu lato, B. mayonii, B. miyamotoi, and Ehrlichia muris-like) were tested; only B. miyamotoi was not distinct from null expectations in all environmental dimensions, based on univariate tests. In the PERMANOVA analyses, the pathogens departed from null expectations for B. microti and B. burgdorferi sensu lato, with smaller niches in B. microti, and larger niches in B. burgdorferi sensu lato, than the vector. More generally, this study shows the value of large-scale data resources with consistent sampling methods, and known absences of key pathogens in particular samples, for answering public health questions, such as the relationship of presence and absence of pathogens in their hosts respect to environmental conditions.


Asunto(s)
Amblyomma , Ixodes , Animales , Ixodes/microbiología , Amblyomma/microbiología , América del Norte , Borrelia/aislamiento & purificación , Borrelia/genética , Borrelia/patogenicidad , Ecosistema , Ehrlichia/aislamiento & purificación , Ehrlichia/genética , Ehrlichia chaffeensis/genética , Vectores Arácnidos/microbiología , Humanos , Enfermedades por Picaduras de Garrapatas/transmisión , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/epidemiología
20.
Insects ; 15(8)2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39194785

RESUMEN

Dermacentor reticulatus (Acari: Ixodidae) is an important arthropod vector in medical and veterinary contexts. Its geographic range is divided into western and eastern populations separated by a "Dermacentor-free zone" in central Poland. Recent faunistic studies showed a new endemic locality of the species in Upper Silesia to the west of the Vistula River (central-southern Poland) and its co-occurrence with I. ricinus. The prevalence of five tick-borne pathogens (TBPs), e.g., B. burgdorferi s.l., Bartonella spp., Rickettsia spp., and Babesia spp., in the ticks was assessed with polymerase chain reaction (PCR) methods. The molecular studies revealed the presence of Rickettsia spp. in 23.8% of the D. reticulatus specimens. In turn, 94.1% of the I. ricinus adults were infected with B. burgdorferi s.l., 11.7 % with Babesia spp., and 5.8% with Rickettsia spp. Coinfections with two TBPs were noted in 17.6% of the I. ricinus. These findings highlight not only the risk of infestation by both tick species in an area previously considered Dermacentor-free, but also the high prevalence of TBPs in the study area. Increased focus on medical and veterinary services appears necessary to diagnose and prevent tick-borne diseases in this region.

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