Prion Disease in Dromedary Camels, Algeria.
Ontology highlight
ABSTRACT:
SUBMITTER: Babelhadj B
PROVIDER: S-EPMC6004840 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:An epidemiological study of Trypanosoma evansi (T. evansi) infection in dromedaries was conducted in four wilayate (localities) of Southern Algeria: Béchar, El Bayadh, Ouargla, Tamanrasset. Between February 2014 and April 2016, 1056 camels of different ages and both sexes from 84 herds were sampled. The prevalence was determined through parasitological examination (Giemsa stained thin smear, GST), serological tests (CATT/T. evansi, ELISA/VSG RoTat 1.2, immune trypanolysis), and molecular tests (T. evansi type A specific RoTat 1.2 PCR and T. evansi type B specific EVAB PCR). The overall prevalence was 2.4 % with GST, 32.4% with CATT/T. evansi, 23.1% with ELISA/VSG RoTat 1.2, 21.0% with immune trypanolysis (TL), 11.2 % with RoTat 1.2 PCR and 0% with EVAB PCR. El Bayadh was the most affected wilaya with 11.8% positives in GST, 74.9% in CATT/T. evansi, 70.1% in ELISA/VSG RoTat 1.2 and 62.2% in immune trypanolysis. Only in Béchar, a non-significantly higher prevalence (13.6%) was observed with RoTat1.2 PCR than in El Bayadh (13.0%). We didn't find any evidence of the presence of T. evansi type B in the study area.
| S-EPMC6656995 | biostudies-literature
Project description:We identified the near-full-genome sequence (29,908 nt, >99%) of Middle East respiratory syndrome coronavirus (MERS-CoV) from a nasal swab specimen from a dromedary camel in Egypt. We found that viruses genetically very similar to human MERS-CoV are infecting dromedaries beyond the Arabian Peninsula, where human MERS-CoV infections have not yet been detected.
| S-EPMC4036765 | biostudies-literature
Project description:Dromedary, or one-humped, camels Camelus dromedarius are an almost exclusively domesticated species that are common in arid areas as both beasts of burden and production animals for meat and milk. Currently, there are approximately 30 million dromedary camels, with highest numbers in Africa and the Middle East. The hardiness of camels in arid regions has made humans more dependent on them, especially as a stable protein source. Camels also carry and may transmit disease-causing agents to humans and other animals. The ability for camels to act as a point source or vector for disease is a concern due to increasing human demands for meat, lack of biosafety and biosecurity protocols in many regions, and a growth in the interface with wildlife as camel herds become sympatric with non-domestic species. We conducted a literature review of camel-borne zoonotic diseases and found that the majority of publications (65%) focused on Middle East respiratory syndrome (MERS), brucellosis, Echinococcus granulosus, and Rift Valley fever. The high fatality from MERS outbreaks during 2012-2016 elicited an immediate response from the research community as demonstrated by a surge of MERS-related publications. However, we contend that other camel-borne diseases such as Yersinia pestis, Coxiella burnetii, and Crimean-Congo hemorrhagic fever are just as important to include in surveillance efforts. Camel populations, particularly in sub-Saharan Africa, are increasing exponentially in response to prolonged droughts, and thus, the risk of zoonoses increases as well. In this review, we provide an overview of the major zoonotic diseases present in dromedary camels, their risk to humans, and recommendations to minimize spillover events.
| S-EPMC7087575 | biostudies-literature
Project description:A recent publication described finding GB virus C (GBV-C) RNA in 4 of 22 dromedary camel sera, and sequence analysis found that these viruses were phylogenetically clustered within human GBV-C isolates. Since all other GB viruses to date form monophyletic groups according to their host species, the close relationship between the sequences generated from camel sera and human GBV-C isolates seemed implausible, leading us to conduct an independent analysis of the sequences. Our investigation found three lines of evidence arguing against GBV-C infection in dromedary camels. First, strong evidence of artifactual sequence generation was identified for some of the sequences. Secondly, the sequence diversity within individual camel sera was 10-152-fold greater than that described for GBV-C within a human host. Finally, GBV-C sequences generated from each camel shared near complete identity with human isolates previously described by the same laboratory. Taken together, these data strongly suggest laboratory contamination. We suggest that additional validation experiments are needed before it is possible to conclude that camels are permissive for GBV-C infection.
| S-EPMC3210887 | biostudies-literature
Project description:The four human coronaviruses (HCoVs) are globally endemic respiratory pathogens. The Middle East respiratory syndrome (MERS) coronavirus (CoV) is an emerging CoV with a known zoonotic source in dromedary camels. Little is known about the origins of endemic HCoVs. Studying these viruses' evolutionary history could provide important insight into CoV emergence. In tests of MERS-CoV-infected dromedaries, we found viruses related to an HCoV, known as HCoV-229E, in 5.6% of 1,033 animals. Human- and dromedary-derived viruses are each monophyletic, suggesting ecological isolation. One gene of dromedary viruses exists in two versions in camels, full length and deleted, whereas only the deleted version exists in humans. The deletion increased in size over a succession starting from camelid viruses via old human viruses to contemporary human viruses. Live isolates of dromedary 229E viruses were obtained and studied to assess human infection risks. The viruses used the human entry receptor aminopeptidase N and replicated in human hepatoma cells, suggesting a principal ability to cause human infections. However, inefficient replication in several mucosa-derived cell lines and airway epithelial cultures suggested lack of adaptation to the human host. Dromedary viruses were as sensitive to the human type I interferon response as HCoV-229E. Antibodies in human sera neutralized dromedary-derived viruses, suggesting population immunity against dromedary viruses. Although no current epidemic risk seems to emanate from these viruses, evolutionary inference suggests that the endemic human virus HCoV-229E may constitute a descendant of camelid-associated viruses. HCoV-229E evolution provides a scenario for MERS-CoV emergence.
| S-EPMC5024591 | biostudies-literature
Project description:Kenya is home to Africa's third largest population of dromedary camels, and production at commercial and local levels are increasingly important. In pastoral and nomadic communities in the arid and semi-arid lands (ASALs), camels play a vital role in food security, while commercial milk production and formalized export markets are rapidly emerging as camel populations expand into non-traditional areas. Until recently, little focus was placed on camels as hosts of zoonotic disease, but the emergence of Middle Eastern respiratory coronavirus (MERS-CoV) in 2012, and the discovery of exposure to the virus in Kenyan camels, highlighted the need for further understanding of this area. This systematised review utilised a robust search strategy to assess the occurrence of camel-associated zoonoses in Kenya and to evaluate the quality of the published literature. Seventy-four studies were identified, covering sixteen pathogens, with an increasing number of good quality studies in recent years. Despite this, the area remains under-researched and there is a lack of robust, high-quality research. Trypanosome spp., Echinococcus granulosus and Brucella spp. appeared most frequently in the literature. Pathogens with the highest reported prevalence were MERS-CoV (0-100%), Echinococcus granulosa (7-60%) and Rift Valley fever virus (7-57%). Exposure to Brucella spp., Coxiella burnetii and Crimean-Congo haemorrhagic fever virus showed higher levels in camel or camel-associated vectors than other livestock species, although brucellosis was the only disease for which there was robust evidence linking camel and human exposure. Zoonotic agents with less severe human health outcomes, such as Dermatophilosus congolensis and contagious ecthyma, were also represented in the literature. This review provides an important summary of the scope and quality of current knowledge. It demonstrates that further research, and improved adherence to robust study design and reporting are essential if the zoonotic risk from camels in Kenya, and elsewhere, is to be better understood.
| S-EPMC7559378 | biostudies-literature
Project description:Reliable and measurable animal-based measures (ABMs) are essential for assessing animal welfare. This study aimed at proposing ABMs for dromedary camels identifying their possible associations with management. Data were collected at a permanent camel market; a total of 76 pens and 528 camels were evaluated. ABMs were collected for each welfare principle (i.e., good feeding, good housing, good health, appropriate behavior), while resources or management-based measures were collected at three levels of investigations (animal, herd, or caretakers). Associations were calculated by generalized linear models. Body condition score and thirst index (ABMs of good feeding) resulted negatively associated with short caretaker's experience, dirty bedding, limited shaded space, feeding and water space, and space allowance (P < 0.05). Resting behaviors and restricted movements (ABMs of good housing) were associated with short caretaker's experience, dirty bedding and water, rationed water distribution, water points in the sun, and presence of hobbles (P < 0.05). Disease, injury, and pain induced by management procedures (ABMs of good health) were negatively associated with short caretaker's experience, presence of hobbles, limited space allowance and shaded space, dirty bedding, and feeding and watering practices (e.g., frequency of distribution, resource quality, location of the troughs; P < 0.05). Response to approaching test and aggressivity (ABMs of Appropriate behavior) were negatively associated with limited space allowance, shaded, feeding and water space, and rationed water distribution (P < 0.05). Overall, the proposed ABMs seems to be appropriate indicators of welfare consequences in camels being able to identify factors related to housing and management practices that may impair or improve camel welfare.
| S-EPMC8568688 | biostudies-literature
Project description:BackgroundTrypanosoma (T.) evansi is a dyskinetoplastic variant of T. brucei that has gained the ability to be transmitted by all sorts of biting flies. T. evansi can be divided into type A, which is the most abundant and found in Africa, Asia and Latin America and type B, which has so far been isolated only from Kenyan dromedary camels. This study aimed at the isolation and the genetic and phenotypic characterisation of type A and B T. evansi stocks from camels in Northern Ethiopia.Methodology/principal findingsT. evansi was isolated in mice by inoculation with the cryopreserved buffy coat of parasitologically confirmed animals. Fourteen stocks were thus isolated and subject to genotyping with PCRs targeting type-specific variant surface glycoprotein genes, mitochondrial minicircles and maxicircles, minisatellite markers and the F1-ATP synthase γ subunit gene. Nine stocks corresponded to type A, two stocks were type B and three stocks represented mixed infections between A and B, but not hybrids. One T. evansi type A stock was completely akinetoplastic. Five stocks were adapted to in vitro culture and subjected to a drug sensitivity assay with melarsomine dihydrochloride, diminazene diaceturate, isometamidium chloride and suramin. In vitro adaptation induced some loss of kinetoplasts within 60 days. No correlation between drug sensitivity and absence of the kinetoplast was observed. Sequencing the full coding sequence of the F1-ATP synthase γ subunit revealed new type-specific single nucleotide polymorphisms and deletions.Conclusions/significanceThis study addresses some limitations of current molecular markers for T. evansi genotyping. Polymorphism within the F1-ATP synthase γ subunit gene may provide new markers to identify the T. evansi type that do not rely on variant surface glycoprotein genes or kinetoplast DNA.
| S-EPMC4818106 | biostudies-literature
Project description:Babesia microti (Apicomplexa: Piroplasmida) causes a medically important tick-borne zoonotic protozoan disease. Egyptian camels are susceptible to Babesia infection; however, just a few cases have been documented. This study aimed to identify Babesia species, specifically Babesia microti, and their genetic diversity in dromedary camels in Egypt and associated hard ticks. Blood and hard tick samples were taken from 133 infested dromedary camels slaughtered in Cairo and Giza abattoirs. The study was conducted from February to November 2021. The 18S rRNA gene was amplified by polymerase chain reaction (PCR) to identify Babesia species. Nested PCR targeting the β-tubulin gene was used to identify B. microti. The PCR results were confirmed by DNA sequencing. Phylogenetic analysis based on the ß-tubulin gene was used to detect and genotype B. microti. Three tick genera were identified in infested camels (Hyalomma, Rhipicephalus, and Amblyomma). Babesia species were detected in 3 out of 133 blood samples (2.3%), while Babesia spp. were not detected in hard ticks by using the 18S rRNA gene. B. microti was identified in 9 out of 133 blood samples (6.8%) and isolated from Rhipicephalus annulatus and Amblyomma cohaerens by the β-tubulin gene. The phylogenetic analysis of the β-tubulin gene revealed that USA-type B. microti was prevalent in Egyptian camels. The results of this study suggested that the Egyptian camels may be infected with Babesia spp. and the zoonotic B. microti strains, which pose a potential risk to public health.
| S-EPMC9941264 | biostudies-literature
Project description:Dromedary camels are a putative source for human infections with Middle East respiratory syndrome coronavirus. We showed that camels sampled in different regions in Kenya during 1992-2013 have antibodies against this virus. High densities of camel populations correlated with increased seropositivity and might be a factor in predicting long-term virus maintenance.
| S-EPMC4111164 | biostudies-literature