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1.
Mol Ecol ; 28(11): 2903-2916, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31074125

RESUMEN

Understanding the dynamics of foot-and-mouth disease virus (FMDV), an endemic and economically constraining disease, is critical in designing control programmes in Africa. This study investigates the evolutionary epidemiology of SAT1 and SAT2 FMDV in Eastern Africa, as well as between cattle and wild African buffalo. Bayesian phylodynamic models were used to analyse SAT1 and SAT2 VP1 gene segments collected between 1975 and 2016, focusing on the SAT1 and SAT2 viruses currently circulating in Eastern Africa. The root state posterior probabilities inferred from our analyses suggest Zimbabwe as the ancestral location for SAT1 currently circulating in Eastern Africa (p = 0.67). For the SAT2 clade, Kenya is inferred to be the ancestral location for introduction of the virus into other countries in Eastern Africa (p = 0.72). Salient (Bayes factor >10) viral dispersal routes were inferred from Tanzania to Kenya, and from Kenya to Uganda for SAT1 and SAT2, respectively. Results suggest that cattle are the source of the SAT1 and SAT2 clades currently circulating in Eastern Africa. In addition, our results suggest that the majority of SAT1 and SAT2 in livestock come from other livestock rather than wildlife, with limited evidence that buffalo serve as reservoirs for cattle. Insights from the present study highlight the role of cattle movements and anthropogenic activities in shaping the evolutionary history of SAT1 and SAT2 in Eastern Africa. While the results may be affected by inherent limitations of imperfect surveillance, our analysis elucidates the dynamics between host species in this region, which is key to guiding disease intervention activities.


Asunto(s)
Virus de la Fiebre Aftosa/clasificación , Virus de la Fiebre Aftosa/fisiología , Fiebre Aftosa/transmisión , Fiebre Aftosa/virología , Filogeografía , África Oriental/epidemiología , Animales , Teorema de Bayes , Fiebre Aftosa/epidemiología , Virus de la Fiebre Aftosa/genética , Genes Virales , Variación Genética , Geografía , Funciones de Verosimilitud , Cadenas de Markov , Especificidad de la Especie
2.
Oecologia ; 187(4): 1095-1105, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29955983

RESUMEN

Stable isotope and elemental ratios in hair are influenced by the environment, including both climate and geology. Stable carbon isotopes can be used to give estimates of the C4/CAM fraction of diets of herbivorous mammals; stable nitrogen isotopes are related to the local water deficit; strontium isotopes are determined by the local geology. We studied hair from rhinos in Kenya to determine spatial patterns in δ13C, δ15N, and 87Sr/86Sr ratios. The samples of rhino hair were collected during Kenya Wildlife Service translocation or veterinary activities. δ13C values showed diets dominated by C3 foods, but in some regions the diet, at least seasonally, contained significant quantities (i.e., > ca. 20%) of C4/CAM foods. δ15N values were related to water deficit, with higher δ15N values in regions with high water deficit. 87Sr/86Sr isotope ratios were found to be related to the local geological substrate suggesting that 87Sr/86Sr isotope ratios are provisionally useful for determining the origins of illegal wildlife materials in Kenya and elsewhere in Africa.


Asunto(s)
Ecología , Perisodáctilos , Animales , Isótopos de Carbono , Kenia , Isótopos de Nitrógeno
3.
BMC Vet Res ; 11: 17, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25644407

RESUMEN

BACKGROUND: Understanding the epidemiology of foot-and-mouth disease (FMD), including roles played by different hosts, is essential for improving disease control. The African buffalo (Syncerus caffer) is a reservoir for the SAT serotypes of FMD virus (FMDV). Large buffalo populations commonly intermingle with livestock in Kenya, yet earlier studies have focused on FMD in the domestic livestock, hence the contribution of buffalo to disease in livestock is largely unknown. This study analysed 47 epithelia collected from FMD outbreaks in Kenyan cattle between 2008 and 2012, and 102 probang and serum samples collected from buffalo in three different Kenyan ecosystems; Maasai-Mara (MME) (n = 40), Tsavo (TSE) (n = 33), and Meru (ME) (n = 29). RESULTS: Antibodies against FMDV non-structural proteins were found in 65 of 102 (64%) sera from buffalo with 44/102 and 53/102 also having neutralising antibodies directed against FMDV SAT 1 and SAT 2, respectively. FMDV RNA was detected in 42% of the buffalo probang samples by RT-qPCR (Cycle Threshold (Ct) ≤32). Two buffalo probang samples were positive by VI and were identified as FMDV SAT 1 and SAT 2 by Ag-ELISA, while the latter assay detected serotypes O (1), A (20), SAT 1 (7) and SAT 2 (19) in the 47 cattle epithelia. VP1 coding sequences were generated for two buffalo and 21 cattle samples. Phylogenetic analyses revealed SAT 1 and SAT 2 virus lineages within buffalo that were distinct from those detected in cattle. CONCLUSIONS: We found that FMDV serotypes O, A, SAT 1 and SAT 2 were circulating among cattle in Kenya and cause disease, but only SAT 1 and SAT 2 viruses were successfully isolated from clinically normal buffalo. The buffalo isolates were genetically distinct from isolates obtained from cattle. Control efforts should focus primarily on reducing FMDV circulation among livestock and limiting interaction with buffalo. Comprehensive studies incorporating additional buffalo viruses are recommended.


Asunto(s)
Enfermedades de los Bovinos/virología , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/virología , Animales , Anticuerpos Antivirales/sangre , Búfalos , Bovinos , Fiebre Aftosa/sangre , Fiebre Aftosa/epidemiología , Virus de la Fiebre Aftosa/clasificación , Regulación Viral de la Expresión Génica/fisiología , Kenia/epidemiología , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo
4.
BMC Vet Res ; 11: 4, 2015 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-25604678

RESUMEN

BACKGROUND: A huge effort in rhinoceros conservation has focused on poaching and habitat loss as factors leading to the dramatic declines in the endangered eastern black rhinoceros (Diceros bicornis michaeli) and the southern white rhinoceros (Ceratotherium simum simum). Nevertheless, the role disease and parasite infections play in the mortality of protected populations has largely received limited attention. Infections with piroplasmosis caused by Babesia bicornis and Theileria bicornis has been shown to be fatal especially in small and isolated populations in Tanzania and South Africa. However, the occurrence and epidemiology of these parasites in Kenyan rhinoceros is not known. RESULTS: Utilizing 18S rRNA gene as genetic marker to detect rhinoceros infection with Babesia and Theileria, we examined blood samples collected from seven rhinoceros populations consisting of 114 individuals of black and white rhinoceros. The goal was to determine the prevalence in Kenyan populations, and to assess the association of Babesia and Theileria infection with host species, age, sex, location, season and population mix (only black rhinoceros comparing to black and white rhinoceros populations). We did not detect any infection with Babesia in the sequenced samples, while the prevalence of T. bicornis in the Kenyan rhinoceros population was 49.12% (56/114). White rhinoceros had significantly higher prevalence of infection (66%) compared to black rhinoceros (43%). The infection of rhinoceros with Theileria was not associated with animal age, sex or location. The risk of infection with Theileria was not higher in mixed species populations compared to populations of pure black rhinoceros. CONCLUSION: In the rhinoceros studied, we did not detect the presence of Babesia bicornis, while Theileria bicornis was found to have a 49.12% prevalence with white rhinoceros showing a higher prevalence (66%) comparing with black rhinoceros (43%). Other factors such as age, sex, location, and population mix were not found to play a significant role.


Asunto(s)
Perisodáctilos/parasitología , Theileria/clasificación , Theileriosis/parasitología , Animales , Femenino , Kenia/epidemiología , Masculino , ARN Protozoario/genética , ARN Ribosómico 18S/genética , Especificidad de la Especie , Theileria/genética , Theileria/aislamiento & purificación , Theileriosis/epidemiología
5.
Sci Rep ; 13(1): 20192, 2023 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-37980384

RESUMEN

In Sub-Saharan Africa (SSA), effective brucellosis control is limited, in part, by the lack of long-term commitments by governments to control the disease and the absence of reliable national human and livestock population-based data to inform policies. Therefore, we conducted a study to establish the national prevalence and develop a risk map for Brucella spp. in cattle to contribute to plans to eliminate the disease in Kenya by the year 2040. We randomly generated 268 geolocations and distributed them across Kenya, proportionate to the area of each of the five agroecological zones and the associated cattle population. Cattle herds closest to each selected geolocation were identified for sampling. Up to 25 cattle were sampled per geolocation and a semi-structured questionnaire was administered to their owners. We tested 6,593 cattle samples for Brucella immunoglobulin G (IgG) antibodies using an Enzyme-linked immunosorbent assay (ELISA). We assessed potential risk factors and performed spatial analyses and prevalence mapping using approximate Bayesian inference implemented via the integrated nested Laplace approximation (INLA) method. The national Brucella spp. prevalence was 6.8% (95% CI: 6.2-7.4%). Exposure levels varied significantly between agro-ecological zones, with a high of 8.5% in the very arid zone with the lowest agricultural potential relative to a low of 0.0% in the agro-alpine zone with the highest agricultural potential. Additionally, seroprevalence increased with herd size, and the odds of seropositivity were significantly higher for females and adult animals than for males or calves. Similarly, animals with a history of abortion, or with multiple reproductive syndromes had higher seropositivity than those without. At the herd level, the risk of Brucella spp. transmission was higher in larger herds, and herds with a history of reproductive problems such as abortion, giving birth to weak calves, or having swollen testes. Geographic localities with high Brucella seroprevalence occurred in northern, eastern, and southern regions of Kenya all primarily characterized by semi-arid or arid agro-ecological zones dominated by livestock pastoralism interspersed with vast areas with mixed livestock-wildlife systems. The large spatial extent of our survey provides compelling evidence for the widespread geographical distribution of brucellosis risk across Kenya in a manner easily understandable for policymakers. Our findings can provide a basis for risk-stratified pilot studies aiming to investigate the cost-effectiveness and efficacy of singular and combined preventive intervention strategies that seek to inform Kenya's Brucellosis Control Policy.


Asunto(s)
Brucella , Brucelosis , Animales , Bovinos , Femenino , Masculino , Embarazo , Crianza de Animales Domésticos , Anticuerpos Antibacterianos , Teorema de Bayes , Brucelosis/epidemiología , Brucelosis/veterinaria , Estudios Transversales , Kenia/epidemiología , Ganado , Factores de Riesgo , Estudios Seroepidemiológicos
6.
Sci Rep ; 13(1): 14787, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684280

RESUMEN

Peste des petits ruminants (PPR) is an infectious viral disease, primarily of small ruminants such as sheep and goats, but is also known to infect a wide range of wild and domestic Artiodactyls including African buffalo, gazelle, saiga and camels. The livestock-wildlife interface, where free-ranging animals can interact with captive flocks, is the subject of scrutiny as its role in the maintenance and spread of PPR virus (PPRV) is poorly understood. As seroconversion to PPRV indicates previous infection and/or vaccination, the availability of validated serological tools for use in both typical (sheep and goat) and atypical species is essential to support future disease surveillance and control strategies. The virus neutralisation test (VNT) and enzyme-linked immunosorbent assay (ELISA) have been validated using sera from typical host species. Still, the performance of these assays in detecting antibodies from atypical species remains unclear. We examined a large panel of sera (n = 793) from a range of species from multiple countries (sourced 2015-2022) using three tests: VNT, ID VET N-ELISA and AU-PANVAC H-ELISA. A sub-panel (n = 30) was also distributed to two laboratories and tested using the luciferase immunoprecipitation system (LIPS) and a pseudotyped virus neutralisation assay (PVNA). We demonstrate a 75.0-88.0% agreement of positive results for detecting PPRV antibodies in sera from typical species between the VNT and commercial ELISAs, however this decreased to 44.4-62.3% in sera from atypical species, with an inter-species variation. The LIPS and PVNA strongly correlate with the VNT and ELISAs for typical species but vary when testing sera from atypical species.


Asunto(s)
Antílopes , Peste de los Pequeños Rumiantes , Virus de la Peste de los Pequeños Rumiantes , Animales , Ovinos , Seroconversión , Peste de los Pequeños Rumiantes/diagnóstico , Anticuerpos , Animales Salvajes , Búfalos , Camelus , Cabras
7.
Parasitology ; 139(12): 1587-95, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23036718

RESUMEN

The sanitary control of threatened wild animals is of pivotal interest for their conservation. This task, however, is highly complex in wildlife/livestock systems. In this paper we report findings from a 2-year cross-sectional study of the epidemiology and attempted control of a Sarcoptes mite infestation in the threatened cheetah population in Masai Mara (Kenya), and discuss its interaction with sympatric wild (lion, wildebeest and Thomson's gazelle) and domestic (dog, cattle and sheep) animals. Sarcoptes scabiei was isolated from cheetahs, Thomson's gazelles, wildebeests, lions, cattle, goats and dogs; Psoroptes ovis, on the other hand, was only isolated from sheep. The prevalence study revealed 12·77% infection rates in cheetahs, 4·7% in dogs, 0·8% in Thomson's gazelles, 0·8% in sheep, 0·09% in cattle, and 0·09% in goats, while it opportunistically affected lions and wildebeest. Our study revealed that prevalence of Sarcoptes mite in cheetah population was not associated with the studied geographical blocks, animal sex or the presence of affected domestic animals. Cheetah infection with S. scabiei was associated with the climatic conditions (dry more than wet season) and the balancing between the total number of Thomson's gazelles and the prevalence of infected individuals. Apparently the high prevalence of mangy gazelles has a negative effect on cheetah; this negative effect was reduced when the number of healthy gazelles was increased. Treatment with injectable ivermectin of the clinically affected wild and domestic animals during the first year of this study was associated with much lower incidence of sarcoptic mange during the second year.


Asunto(s)
Acinonyx/parasitología , Animales Salvajes/parasitología , Ganado/parasitología , Escabiosis/veterinaria , Animales , Antílopes , Antiparasitarios/uso terapéutico , Bovinos , Perros , Cabras , Kenia , Infestaciones por Ácaros/tratamiento farmacológico , Infestaciones por Ácaros/epidemiología , Infestaciones por Ácaros/veterinaria , Prevalencia , Psoroptidae/fisiología , Sarcoptes scabiei/fisiología , Escabiosis/tratamiento farmacológico , Escabiosis/epidemiología , Estaciones del Año , Ovinos
8.
BMC Vet Res ; 8: 110, 2012 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-22776804

RESUMEN

BACKGROUND: One of the main aims of forensic investigation is the detection and location of people and substances of interest, such as missing people and illegal drugs. Dogs (Canis lupus var. familiaris) have had an important role in legal and forensic investigations for decades; nonetheless canines' keen sense of smell has never been utilized in either the surveillance or control of wildlife diseases. The rapid removal and treatment of infected carcasses and/or sick animals is a key task in the management of infectious diseases, but it is usually difficult or impractical to carry out in the wild. RESULTS: In this paper we report on a study running over a period of 15 years, in which - for the first time to our knowledge - two disease-detector dogs were trained to follow the scent of Sarcoptes-infected animals and to find carcasses, even under the snow, and apparently no false positives were detected in fieldwork. Sarcoptic mange-detector dogs were used to collect the carcasses of 292 mangy wild animals and to identify, separate from their herd, and capture 63 mange-infected wild animals in the Italian Alps. CONCLUSIONS: Properly trained disease-detector dogs are an efficient and straightforward tool for surveillance and control of sarcoptic mange in affected wild animal populations.


Asunto(s)
Animales Salvajes , Brotes de Enfermedades/veterinaria , Perros , Rupicapra , Escabiosis/veterinaria , Animales , Enfermedades Transmisibles Emergentes/veterinaria , Conservación de los Recursos Naturales , Femenino , Italia/epidemiología , Masculino , Vigilancia de la Población , Escabiosis/epidemiología , Escabiosis/parasitología , Factores de Tiempo
9.
Forensic Sci Med Pathol ; 8(3): 280-4, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21814832

RESUMEN

The development of non-manipulative molecular tools to determine the origin of parasite infections in the animal trade (if infected before their export or import) is of great interest worldwide for both the animal trade industry and for animal welfare. Molecular tools have a wide range of applications, including forensic identification, wildlife preservation and conservation, veterinary public health protection, and food safety. Nonetheless, genetic markers were not reported to detect the source of infection in the animal trade. In this study we tested the applicability of molecular tools to detect the origin of Sarcoptes mite infection of wildebeest imported by the United Arab Emirate (UAE) from Tanzania. Using one multiplex of seven microsatellite markers and control samples from UAE, Kenya and Italy, we demonstrated the usefulness of the multiplex STR-typing as a molecular tool of pivotal interest to help commercialist, authorities, and conservationists, to identify the geographical origin of parasitic infections.


Asunto(s)
Comercio , ADN/análisis , Ciencias Forenses/métodos , Reacción en Cadena de la Polimerasa Multiplex , Enfermedades Parasitarias en Animales/parasitología , Parasitología/métodos , Rumiantes/parasitología , Sarcoptes scabiei/genética , Escabiosis/veterinaria , Animales , Antiparasitarios/administración & dosificación , Femenino , Marcadores Genéticos , Ivermectina/administración & dosificación , Masculino , Repeticiones de Microsatélite , Enfermedades Parasitarias en Animales/diagnóstico , Enfermedades Parasitarias en Animales/tratamiento farmacológico , Enfermedades Parasitarias en Animales/transmisión , Valor Predictivo de las Pruebas , Escabiosis/diagnóstico , Escabiosis/tratamiento farmacológico , Escabiosis/parasitología , Escabiosis/transmisión , Tanzanía , Emiratos Árabes Unidos
10.
Microbiol Resour Announc ; 11(10): e0058422, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36094180

RESUMEN

Nearly complete genomes of 49 novel foot-and-mouth disease virus (FMDV) SAT1 strains acquired from oropharyngeal fluid samples from asymptomatic African Cape buffalo in Kenya in 2016 were determined. Sequences were from primary passage or plaque-purified dually SAT1/SAT2-infected samples. These sequences are important for elucidation of the molecular epidemiology of persistent and subclinical FMDV infections.

11.
Microbiol Resour Announc ; 11(10): e0058522, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36094207

RESUMEN

Foot-and-mouth disease virus (FMDV) SAT2 sequences were acquired from Cape buffalo in Kenya in 2016, from either primary passage (n = 38) or plaque purification of dually SAT1/SAT2-infected samples (n = 61). All samples were derived from asymptomatic animals. These sequences contribute to our understanding of FMDV diversity in reservoirs and during subclinical FMDV infections.

12.
PLoS Negl Trop Dis ; 16(8): e0010596, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35939503

RESUMEN

BACKGROUND: Co-infection, especially with pathogens of dissimilar genetic makeup, may result in a more devastating impact on the host. Investigations on co-infection with neglected zoonotic pathogens in wildlife are necessary to inform appropriate prevention and control strategies to reduce disease burden in wildlife and the potential transmission of these pathogens between wildlife, livestock and humans. This study assessed co-exposure of various Kenyan wildflife species with Brucella spp, Coxiella burnetii and Rift Valley fever virus (RVFV). METHODOLOGY: A total of 363 sera from 16 different wildlife species, most of them (92.6%) herbivores, were analysed by Enzyme-linked immunosorbent assay (ELISA) for IgG antibodies against Brucella spp, C. burnetii and RVFV. Further, 280 of these were tested by PCR to identify Brucella species. RESULTS: Of the 16 wildlife species tested, 15 (93.8%) were seropositive for at least one of the pathogens. Mean seropositivities were 18.9% (95% CI: 15.0-23.3) for RVFV, 13.7% (95% CI: 10.3-17.7) for Brucella spp and 9.1% (95% CI: 6.3-12.5) for C. burnetii. Buffaloes (n = 269) had higher seropositivity for Brucella spp. (17.1%, 95% CI: 13.0-21.7%) and RVFV (23.4%, 95% CI: 18.6-28.6%), while giraffes (n = 36) had the highest seropositivity for C. burnetii (44.4%, 95% CI: 27.9-61.9%). Importantly, 23 of the 93 (24.7%) animals positive for at least one pathogen were co-exposed, with 25.4% (18/71) of the positive buffaloes positive for brucellosis and RVFV. On molecular analysis, Brucella DNA was detected in 46 (19.5%, CI: 14.9-24.7) samples, with 4 (8.6%, 95% CI: 2.2-15.8) being identified as B. melitensis. The Fisher's Exact test indicated that seropositivity varied significantly within the different animal families, with Brucella (p = 0.013), C. burnetii (p = <0.001) and RVFV (p = 0.007). Location was also significantly associated (p = <0.001) with Brucella spp. and C. burnetii seropositivities. CONCLUSION: Of ~20% of Kenyan wildlife that are seropositive for Brucella spp, C. burnetii and RVFV, almost 25% indicate co-infections with the three pathogens, particularly with Brucella spp and RVFV.


Asunto(s)
Brucella , Coinfección , Coxiella burnetii , Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Animales , Animales Salvajes , Brucella/genética , Búfalos , Coinfección/epidemiología , Coinfección/veterinaria , Coxiella burnetii/genética , Humanos , Kenia/epidemiología , Virus de la Fiebre del Valle del Rift/genética , Estudios Seroepidemiológicos , Zoonosis
13.
Viruses ; 14(5)2022 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-35632639

RESUMEN

African buffalo are the natural reservoirs of the SAT serotypes of foot-and-mouth disease virus (FMDV) in sub-Saharan Africa. Most buffalo are exposed to multiple FMDV serotypes early in life, and a proportion of them become persistently infected carriers. Understanding the genetic diversity and evolution of FMDV in carrier animals is critical to elucidate how FMDV persists in buffalo populations. In this study, we obtained oropharyngeal (OPF) fluid from naturally infected African buffalo, and characterized the genetic diversity of FMDV. Out of 54 FMDV-positive OPF, 5 were co-infected with SAT1 and SAT2 serotypes. From the five co-infected buffalo, we obtained eighty-nine plaque-purified isolates. Isolates obtained directly from OPF and plaque purification were sequenced using next-generation sequencing (NGS). Phylogenetic analyses of the sequences obtained from recombination-free protein-coding regions revealed a discrepancy in the topology of capsid proteins and non-structural proteins. Despite the high divergence in the capsid phylogeny between SAT1 and SAT2 serotypes, viruses from different serotypes that were collected from the same host had a high genetic similarity in non-structural protein-coding regions P2 and P3, suggesting interserotypic recombination. In two of the SAT1 and SAT2 co-infected buffalo identified at the first passage of viral isolation, the plaque-derived SAT2 genomes were distinctly grouped in two different genotypes. These genotypes were not initially detected with the NGS from the first passage (non-purified) virus isolation sample. In one animal with two SAT2 haplotypes, one plaque-derived chimeric sequence was found. These findings demonstrate within-host evolution through recombination and point mutation contributing to broad viral diversity in the wildlife reservoir. These mechanisms may be critical to FMDV persistence at the individual animal and population levels, and may contribute to the emergence of new viruses that have the ability to spill-over to livestock and other wildlife species.


Asunto(s)
Coinfección , Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Animales Salvajes , Búfalos , Proteínas de la Cápside/genética , Coinfección/veterinaria , Fiebre Aftosa/epidemiología , Kenia , Filogenia , Serogrupo
14.
Front Microbiol ; 13: 932224, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847110

RESUMEN

Focusing on the utility of ticks as xenosurveillance sentinels to expose circulating pathogens in Kenyan drylands, host-feeding ticks collected from wild ungulates [buffaloes, elephants, giraffes, hartebeest, impala, rhinoceros (black and white), zebras (Grévy's and plains)], carnivores (leopards, lions, spotted hyenas, wild dogs), as well as regular domestic and Boran cattle were screened for pathogens using metagenomics. A total of 75 host-feeding ticks [Rhipicephalus (97.3%) and Amblyomma (2.7%)] collected from 15 vertebrate taxa were sequenced in 46 pools. Fifty-six pathogenic bacterial species were detected in 35 pools analyzed for pathogens and relative abundances of major phyla. The most frequently observed species was Escherichia coli (62.8%), followed by Proteus mirabilis (48.5%) and Coxiella burnetii (45.7%). Francisella tularemia and Jingmen tick virus (JMTV) were detected in 14.2 and 13% of the pools, respectively, in ticks collected from wild animals and cattle. This is one of the first reports of JMTV in Kenya, and phylogenetic reconstruction revealed significant divergence from previously known isolates and related viruses. Eight fungal species with human pathogenicity were detected in 5 pools (10.8%). The vector-borne filarial pathogens (Brugia malayi, Dirofilaria immitis, Loa loa), protozoa (Plasmodium spp., Trypanosoma cruzi), and environmental and water-/food-borne pathogens (Entamoeba histolytica, Encephalitozoon intestinalis, Naegleria fowleri, Schistosoma spp., Toxoplasma gondii, and Trichinella spiralis) were detected. Documented viruses included human mastadenovirus C, Epstein-Barr virus and bovine herpesvirus 5, Trinbago virus, and Guarapuava tymovirus-like virus 1. Our findings confirmed that host-feeding ticks are an efficient sentinel for xenosurveillance and demonstrate clear potential for wildlife-livestock-human pathogen transfer in the Kenyan landscape.

15.
Transbound Emerg Dis ; 69(3): 927-942, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33756055

RESUMEN

Sarcoptic mange, a skin infestation caused by the mite Sarcoptes scabiei, is an emerging disease for some species of wildlife, potentially jeopardizing their welfare and conservation. Sarcoptes scabiei has a near-global distribution facilitated by its forms of transmission and use of a large diversity of host species (many of those with broad geographic distribution). In this review, we synthesize the current knowledge concerning the geographic and host taxonomic distribution of mange in wildlife, the epidemiological connections between species, and the potential threat of sarcoptic mange for wildlife conservation. Recent sarcoptic mange outbreaks in wildlife appear to demonstrate ongoing geographic spread, increase in the number of hosts and increased virulence. Sarcoptic mange has been reported in at least 12 orders, 39 families and 148 species of domestic and wild mammals, making it one of the most generalist ectoparasites of mammals. Taxonomically, the orders with most species found infested so far include Perissodactyla (67% species from the entire order), Artiodactyla (47%), and Diprotodontia (67% from this order). This suggests that new species from these mammal orders are likely to suffer cross-species transmission and be reported positive to sarcoptic mange as surveillance improves. We propose a new agenda for the study of sarcoptic mange in wildlife, including the study of the global phylogeography of S. scabiei, linkages between ecological host traits and sarcoptic mange susceptibility, immunology of individuals and species, development of control strategies in wildlife outbreaks and the effects of global environmental change in the sarcoptic mange system. The ongoing transmission globally and sustained spread among areas and wildlife species make sarcoptic mange an emerging panzootic in wildlife. A better understanding of sarcoptic mange could illuminate the aspects of ecological and evolutionary drivers in cross-species transmission for many emerging diseases.


Asunto(s)
Escabiosis , Animales , Animales Salvajes/parasitología , Brotes de Enfermedades , Humanos , Mamíferos , Sarcoptes scabiei , Escabiosis/epidemiología , Escabiosis/veterinaria
16.
PLoS One ; 16(9): e0244119, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34478450

RESUMEN

BACKGROUND: To improve early detection of emerging infectious diseases in sub-Saharan Africa (SSA), many of them zoonotic, numerous electronic animal disease-reporting systems have been piloted but not implemented because of cost, lack of user friendliness, and data insecurity. In Kenya, we developed and rolled out an open-source mobile phone-based domestic and wild animal disease reporting system and collected data over two years to investigate its robustness and ability to track disease trends. METHODS: The Kenya Animal Biosurveillance System (KABS) application was built on the Java® platform, freely downloadable for android compatible mobile phones, and supported by web-based account management, form editing and data monitoring. The application was integrated into the surveillance systems of Kenya's domestic and wild animal sectors by adopting their existing data collection tools, and targeting disease syndromes prioritized by national, regional and international animal and human health agencies. Smartphone-owning government and private domestic and wild animal health officers were recruited and trained on the application, and reports received and analyzed by Kenya Directorate of Veterinary Services. The KABS application performed automatic basic analyses (frequencies, spatial distribution), which were immediately relayed to reporting officers as feedback. RESULTS: Of 697 trained domestic animal officers, 662 (95%) downloaded the application, and >72% of them started reporting using the application within three months. Introduction of the application resulted in 2- to 14-fold increase in number of disease reports when compared to the previous year (relative risk = 14, CI 13.8-14.2, p<0.001), and reports were more widely distributed. Among domestic animals, food animals (cattle, sheep, goats, camels, and chicken) accounted for >90% of the reports, with respiratory, gastrointestinal and skin diseases constituting >85% of the reports. Herbivore wildlife (zebra, buffalo, elephant, giraffe, antelopes) accounted for >60% of the wildlife disease reports, followed by carnivores (lions, cheetah, hyenas, jackals, and wild dogs). Deaths, traumatic injuries, and skin diseases were most reported in wildlife. CONCLUSIONS: This open-source system was user friendly and secure, ideal for rolling out in other countries in SSA to improve disease reporting and enhance preparedness for epidemics of zoonotic diseases.


Asunto(s)
Enfermedades de los Animales , Animales , Bovinos , Kenia , Ganado , Vigilancia de Guardia , Ovinos
17.
Viruses ; 13(5)2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-34066336

RESUMEN

Peste des petits ruminants (PPR) is a viral disease of goats and sheep that occurs in Africa, the Middle East and Asia with a severe impact on livelihoods and livestock trade. Many wild artiodactyls are susceptible to PPR virus (PPRV) infection, and some outbreaks have threatened endangered wild populations. The role of wild species in PPRV epidemiology is unclear, which is a knowledge gap for the Global Strategy for the Control and Eradication of PPR. These studies aimed to investigate PPRV infection in wild artiodactyls in the Greater Serengeti and Amboseli ecosystems of Kenya and Tanzania. Out of 132 animals purposively sampled in 2015-2016, 19.7% were PPRV seropositive by ID Screen PPR competition enzyme-linked immunosorbent assay (cELISA; IDvet, France) from the following species: African buffalo, wildebeest, topi, kongoni, Grant's gazelle, impala, Thomson's gazelle, warthog and gerenuk, while waterbuck and lesser kudu were seronegative. In 2018-2019, a cross-sectional survey of randomly selected African buffalo and Grant's gazelle herds was conducted. The weighted estimate of PPRV seroprevalence was 12.0% out of 191 African buffalo and 1.1% out of 139 Grant's gazelles. All ocular and nasal swabs and faeces were negative by PPRV real-time reverse transcription-polymerase chain reaction (RT-qPCR). Investigations of a PPR-like disease in sheep and goats confirmed PPRV circulation in the area by rapid detection test and/or RT-qPCR. These results demonstrated serological evidence of PPRV infection in wild artiodactyl species at the wildlife-livestock interface in this ecosystem where PPRV is endemic in domestic small ruminants. Exposure to PPRV could be via spillover from infected small ruminants or from transmission between wild animals, while the relatively low seroprevalence suggests that sustained transmission is unlikely. Further studies of other major wild artiodactyls in this ecosystem are required, such as impala, Thomson's gazelle and wildebeest.


Asunto(s)
Animales Salvajes/virología , Ecosistema , Ganado/virología , Peste de los Pequeños Rumiantes/epidemiología , Peste de los Pequeños Rumiantes/virología , Virus de la Peste de los Pequeños Rumiantes/fisiología , Enfermedades de los Animales/epidemiología , Enfermedades de los Animales/historia , Enfermedades de los Animales/virología , Animales , Estudios Transversales , Brotes de Enfermedades , Geografía Médica , Historia del Siglo XXI , Kenia/epidemiología , Peste de los Pequeños Rumiantes/historia , Virus de la Peste de los Pequeños Rumiantes/clasificación , Vigilancia en Salud Pública , Estudios Seroepidemiológicos , Tanzanía/epidemiología
18.
Animals (Basel) ; 10(2)2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32085568

RESUMEN

Etorphine-azaperone immobilisation was evaluated for translocation of Masai giraffes. Nine giraffes were darted with 0.012 ± 0.001 mg/kg etorphine and 0.07 ± 0.01 mg/kg azaperone. Once ataxic, giraffes were roped for recumbency and restrained manually. Naltrexone (3 mg/mg etorphine) was immediately given intravenously to reverse etorphine-related side effects. Protocol evaluation included physiological monitoring, blood-gas analyses, anaesthetic times, and quality scores (1 = excellent, 4 = poor). Sedation onset and recumbency were achieved in 2.6 ± 0.8 and 5.6 ± 1.4 min. Cardio-respiratory function (HR = 70 ± 16, RR = 32 ± 8, MAP = 132 ± 16) and temperature (37.8 ± 0.5) were stable. Arterial gas analysis showed hypoxaemia in some individuals (PaO2 = 67 ± 8 mmHg) and metabolic acidosis (pH = 7.23 ± 0.05, PaCO2 = 34 ± 4 mmHg, HCO3- = 12.9 ± 1.2 mmol/l). Minor startle response occurred, while higher induction-induced excitement correlated to longer inductions, worse restraint, and decreased HCO3-. After 19 ± 3.5 min of restraint, giraffes were allowed to stand and were loaded onto a chariot. Immobilisations were good and scored 2 (1-3). Inductions and recoveries were smooth and scored 1 (1-2). Translocations were uneventful and no complications occurred in 14-days boma follow-up.

19.
Transbound Emerg Dis ; 67(5): 2206-2221, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32303117

RESUMEN

Quantitative knowledge on the contribution of African buffalo to the epidemiology of foot-and-mouth disease virus (FMDV) in East Africa is lacking, and this information is essential for the design of control programs in the region. The objective of this study was to investigate the epidemiology of FMDV in buffalo, including the role of buffalo in the circulation of FMDV in livestock populations. We collected blood and oropharyngeal fluids from 92 wild buffalo and 98 sympatric cattle in central Kenya and sequenced the virus' VP1 coding region. We show that FMDV has a high seroprevalence in buffalo (~77%) and targeted cattle (~93%). In addition, we recovered 80 FMDV sequences from buffalo, all of which were serotype SAT1 and SAT2, and four serotype O and A sequences from sympatric cattle. Notably, six individual buffalo were co-infected with both SAT1 and SAT2. Amongst sympatric buffalo and cattle, the fact that no SAT1 or 2 sequences were found in cattle suggests that transmission of FMDV from buffalo to sympatric cattle is rare. Similarly, there was no evidence that serotype O and A sequences found in cattle were transmitted to buffalo. However, viruses from FMDV outbreaks in cattle elsewhere in Kenya were closely related to SAT1 and SAT2 viruses found in buffalo in this study, suggesting that FMDV in cattle and buffalo do not constitute independently evolving populations. We also show that fine-scale geographic features, such as rivers, influence the circulation of FMDV in buffalo and that social segregation amongst sympatric herds may limit between-herd transmission. These results significantly advance our understanding of the ecology and molecular epidemiology of FMDV at wildlife-livestock interfaces in East Africa and will help to inform the design of control and surveillance strategies for this disease in the region.

20.
Microbiol Resour Announc ; 8(35)2019 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-31467103

RESUMEN

This is the first report of two near-complete genome sequences of foot-and-mouth disease virus (FMDV) serotype O from Kenya. The viruses were isolated from bovine epithelium collected in 2014 and 2016 from local FMD outbreaks. These full-genome sequences are critical for improving the understanding of regional FMDV molecular epidemiology.

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