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1.
Parasitol Res ; 123(8): 298, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141116

RESUMO

Bovine neosporosis is a widespread parasitic disease associated with significant economic losses. Its effects on the reproductive performance of cows have resulted in losses that run into the hundreds of millions of US dollars in dairy industries in various countries (Reichel et al., Int J Parasitol 43:133-142, 2013). Due to outdated and scant information on the occurrence of Neospora caninum infection in South Africa, the study aimed to determine the seroprevalence and risk factors associated with infection in dairy cattle in South Africa. A total of 1401 blood samples were randomly collected from cattle on 48 dairy farms in seven of the nine provinces in South Africa. A close-ended questionnaire was used in a cross-sectional study to obtain farm-level and animal-level data. Serological testing was done using a commercial IDvet Screen® Neospora caninum Indirect ELISA. An overall seroprevalence, adjusted for test sensitivity and specificity, of 2.3% (95% CI, 1.3-4.1) was detected and 48% (23/48) of sampled farms had at least one animal testing positive. The highest seroprevalence of N. caninum was in the KwaZulu-Natal province with 7.5% (95% CI, 3.8-14.3), and the lowest in Western Cape with 0.1% (95% CI, 0-1.2). The highest within-farm seroprevalence of 25% was detected on a farm in the North West Province. In a multivariable logistic regression model, the odds of N. caninum seropositivity were higher in Holstein-Friesian cattle when compared to other breeds. Good hygiene was identified as a protective factor. Cattle left out on pasture had increased odds of testing positive for N. caninum compared to those that were penned. The odds of testing seropositive for N. caninum was higher on farms that practised segregation of cattle into different age groups. The purchase of replacement animals was a significant risk factor, as open herds had increased odds of N. caninum seropositivity. Cattle on farms that did not have a specific calving location were more likely to be seropositive. This is the first such study in South Africa and shows that N. caninum is widely distributed in the country at a low seroprevalence, but it may be a cause of concern on certain farms.


Assuntos
Anticorpos Antiprotozoários , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Bovinos , Coccidiose/epidemiologia , Coccidiose/veterinária , Coccidiose/parasitologia , África do Sul/epidemiologia , Estudos Soroepidemiológicos , Neospora/imunologia , Neospora/isolamento & purificação , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Fatores de Risco , Estudos Transversais , Anticorpos Antiprotozoários/sangue , Feminino , Ensaio de Imunoadsorção Enzimática/veterinária , Indústria de Laticínios , Inquéritos e Questionários
2.
Artigo em Inglês | MEDLINE | ID: mdl-35819404

RESUMO

A Gram-negative rod with a single polar flagellum was isolated from a freshwater reservoir used for household purposes in Boane District, near Maputo, Mozambique, and designated as strain DB1T. Growth was observed at 30-42 °C (optimum, 30-37 °C) and with 0.5-1.5 % NaCl. Whole-genome-, rpoD- and 16S rRNA-based phylogenies revealed this isolate to be distant from other Pseudomonas species with Pseudomonas resinovorans, Pseudomonas furukawaii and Pseudomonas lalkuanensis being the closest relatives. Phenotypic analyses of strain DB1T showed marked differences with respect to type strains P. resinovorans CCUG 2473T, P. lalkuanensis CCUG 73691T, P. furukawaii CCUG 75672T and Pseudomonas otiditis CCUG 55592T. Taken together, our results indicate that strain DB1T is a representative of a novel species within the genus Pseudomonas for which the name Pseudomonas boanensis is proposed. The type strain is DB1T (=CCUG 62977T=CECT 30359T).


Assuntos
Ácidos Graxos , Rios , Bactérias , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Moçambique , Hibridização de Ácido Nucleico , Filogenia , Pseudomonas , RNA Ribossômico 16S/genética , Rios/microbiologia , Análise de Sequência de DNA , Água
3.
Exp Appl Acarol ; 86(3): 407-418, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35212871

RESUMO

Rickettsia africae is a gram-negative bacterium, which causes African tick bite fever (ATBF) in humans. ATBF is a febrile disease mainly affecting travellers to southern Africa. This bacterium is known to be transmitted by Amblyomma hebraeum and Amblyomma variegatum ticks. In southern Africa, the principal vector is A. hebraeum. Febrile disease is a serious issue in the study area. There is a high prevalence of non-malaria illness caused by Rickettsia, so there is a need to have more knowledge on these species. Infection rates and transovarial transmission efficiency of R. africae in A. hebraeum ticks were investigated in a rural area of Mpumalanga province, South Africa. Adult and engorged A. hebraeum female ticks were collected from cattle. Larvae were collected by dragging a cloth at ground level using 100 steps, equivalent to an area of 100 m2. Tick identification was performed according to standard taxonomic keys using a microscope. Engorged ticks were incubated to oviposit and egg masses were collected. DNA was extracted from the ticks, larvae and egg masses, and screened for gltA and ompA genes, using quantitative real-time PCR and conventional PCR, respectively. Positive ompA amplicons were sequenced and phylogenetic analysis showed 99.8-100% identity with R. africae. Infection rates were 13.7 and 12.7% for adults and larvae, respectively. Transovarial transmission of R. africae in A. hebraeum from this study was 85.7%. The results provide a clear indication that people living in the study area and travellers that visit the area are at risk of contracting ATBF.


Assuntos
Doenças dos Bovinos , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Amblyomma , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Humanos , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Rickettsia/genética , África do Sul/epidemiologia , Carrapatos/microbiologia
4.
Trop Anim Health Prod ; 55(1): 28, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36574053

RESUMO

This study assessed the knowledge, attitudes and practices of livestock farmers in Namibia's Khomas region and animal health practitioners (veterinarians and animal health technicians) in the whole country concerning neosporosis and toxoplasmosis. Structured questionnaires were used, and a total of 63 farmers and 51 animal health practitioners responded out of an estimated 560 farmers in the Khomas region and 300 veterinarians and veterinary technicians in the country. Only 15.9% of the livestock farmers (n = 63) had heard about neosporosis or toxoplasmosis or knew how animals get infected (p < 0.0001). Only 5% of the farmers knew the risks associated with keeping dogs and cats concerning neosporosis and toxoplasmosis, respectively (p < 0.0001). None of the 51 animal health practitioners routinely requested Neospora caninum or Toxoplasma gondii laboratory tests in cases of cattle, sheep or goat abortions. Although all animal health practitioners indicated they routinely interacted with livestock farmers, none regularly discussed neosporosis or toxoplasmosis. Only 3.9% of animal health practitioners (n = 51) indicated that they had ever discussed either neosporosis or toxoplasmosis at a farmers' gathering (p < 0.0001), and only 21.6% had talked to at least one cat owner about toxoplasmosis in the previous 12 months (p < 0.0001). The authors concluded that farmers in the Khomas region were generally unaware of neosporosis and toxoplasmosis but could change their attitudes and practices if educated. The animal health practitioners lacked a deeper understanding and appreciation of the two diseases, which is required to cultivate enough confidence to educate farmers. Sharing this research and other relevant information on the two diseases at farmers' meetings, veterinary congresses, journals and newsletters could help educate farmers and animal health practitioners. Such platforms are likely to succeed because both these groups use these forums to get new information.


Assuntos
Doenças do Gato , Coccidiose , Doenças do Cão , Doenças das Cabras , Neospora , Toxoplasma , Toxoplasmose Animal , Gravidez , Feminino , Animais , Bovinos , Ovinos , Gatos , Cães , Humanos , Namíbia/epidemiologia , Doenças do Gato/epidemiologia , Fazendeiros , Conhecimentos, Atitudes e Prática em Saúde , Coccidiose/veterinária , Estudos Soroepidemiológicos , Doenças do Cão/epidemiologia , Cabras , Doenças das Cabras/epidemiologia , Doenças das Cabras/prevenção & controle
5.
Parasitol Res ; 120(3): 1097-1102, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33415400

RESUMO

The diversity of ticks and tick-borne pathogens (TBPs) infesting domestic animals in Tchicala-Tcholoanga, Angola, in 2016 was investigated. Seventeen tick species were recorded, Amblyomma pomposum being the most abundant on cattle (40%), goats (38%) and sheep (35%); Rhipicephalus turanicus was the most abundant on dogs (46%). This study presents new records of Haemaphysalis paraleachi, R. compositus, R. kochi and R. sulcatus in Angola, the first georeferenced population of Ha. leachi in southern Africa and the second record of R. microplus in Angola. Using the reverse line blot (RLB) hybridisation assay, fifteen TBP species were detected in blood samples from cattle (n = 88), goats (n = 82), sheep (n = 85) and dogs (n = 85). F The most frequently detected species were Theileria velifera in cattle (78%), Theileria ovis in sheep (80%) and Babesia vogeli in dogs (35%). Species-specific quantitative PCR assays detected Babesia bigemina in 43% (35/80) of blood samples of cattle, while E. ruminantium was detected in 4% (3/70) of blood samples and in 7% of A. pomposum ticks. Anaplasma platys was detected from cattle (18%) and sheep (6%) during RLB analysis. These findings constitute pioneering research in Angola.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças do Cão/epidemiologia , Doenças das Cabras/epidemiologia , Doenças dos Ovinos/epidemiologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Anaplasma/genética , Anaplasma/isolamento & purificação , Angola/epidemiologia , Animais , Babesia/genética , Babesia/isolamento & purificação , Bovinos , Doenças dos Bovinos/parasitologia , Estudos Transversais , Doenças do Cão/parasitologia , Cães , Feminino , Doenças das Cabras/parasitologia , Cabras , Ixodidae/classificação , Ixodidae/fisiologia , Gado , Masculino , Ovinos , Doenças dos Ovinos/parasitologia , Theileria/genética , Theileria/isolamento & purificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/classificação , Carrapatos/fisiologia
6.
BMC Microbiol ; 20(1): 225, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32723369

RESUMO

BACKGROUND: Mosquito-borne diseases involving arboviruses represent expanding threats to sub-Saharan Africa imposing as considerable burden to human and veterinary public health. In Mozambique over one hundred species of potential arbovirus mosquito vectors have been identified, although their precise role in maintaining such viruses in circulation in the country remains to be elucidated. The aim of this study was to screen for the presence of flaviviruses, alphaviruses and bunyaviruses in mosquitoes from different regions of Mozambique. RESULTS: Our survey analyzed 14,519 mosquitoes, and the results obtained revealed genetically distinct insect-specific flaviviruses, detected in multiple species of mosquitoes from different genera. In addition, smaller flavivirus-like NS5 sequences, frequently detected in Mansonia seemed to correspond to defective viral sequences, present as viral DNA forms. Furthermore, three lineages of putative members of the Phenuiviridae family were also detected, two of which apparently corresponding to novel viral genetic lineages. CONCLUSION: This study reports for the first-time novel insect-specific flaviviruses and novel phenuiviruses, as well as frequent flavivirus-like viral DNA forms in several widely known vector species. This unique work represents recent investigation of virus screening conducted in mosquitoes from Mozambique and an important contribution to inform the establishment of a vector control program for arbovirus in the country and in the region.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Vírus de RNA/genética , Alphavirus/classificação , Alphavirus/genética , Alphavirus/isolamento & purificação , Animais , Arbovírus/classificação , Arbovírus/genética , Arbovírus/isolamento & purificação , Bunyaviridae/classificação , Bunyaviridae/genética , Bunyaviridae/isolamento & purificação , Linhagem Celular , Culicidae/classificação , DNA Viral/genética , Flavivirus/classificação , Flavivirus/genética , Flavivirus/isolamento & purificação , Mosquitos Vetores/classificação , Moçambique , Filogenia , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , RNA Viral/genética , Proteínas Virais/genética
7.
Parasitol Res ; 117(2): 429-436, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29264718

RESUMO

African animal trypanosomosis is a debilitating tsetse-transmitted parasitic disease of sub-Saharan Africa. Therapeutic and prophylactic drugs were introduced more than 50 years ago, and drug resistance is increasingly reported. In a cross-sectional study, 467 cattle were microscopically screened for trypanosomes. Samples were collected in May-July 2014 from five villages (Botao, Mungama, Zalala-Electrosul, Zalala-Madal, and Namitangurine) in Nicoadala district, Zambezia province. To evaluate treatment efficacy, trypanosome-positive animals in each village were randomly assigned to two groups, one treated with 0.5 mg/kg b.w. isometamidium (Inomidium®), the second with 3.5 mg/kg b.w. diminazene (Inomazene®). Cattle were microscopically monitored at days 0, 14, and 28 post-treatment. At day 28, trypanocides were swapped to investigate single or multiple resistance. Microscopically negative samples from the monitoring days were tested using 18S-PCR-RFLP. 22.9% (107/467) was found positive on day 0. On day 14, nine animals in Botao and seven in Mungama were positive. On day 28, in Botao, four animals from the diminazene group and four from the isometamidium group were positive. In Mungama, four animals from the diminazene group were positive on day 28. On day 42, six animals (9%) in Botao and two (9.5%) in Mungama remained positive after drug swap. No relapses occurred in Namitangurine. The 18S-PCR-RFLP consistently detected more positive than microscopy: indeed, positives reached 12, 13, and 8 in Botao and 9, 7, and 4 in Mungama, at days 14, 28, and 42, respectively. Single- and multi-drug resistance in Nicoadala district, Zambezia province, is thus here confirmed. This should be considered when choosing control options.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Diminazena/farmacologia , Fenantridinas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma congolense/efeitos dos fármacos , Tripanossomíase Africana/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Estudos Transversais , Resistência a Múltiplos Medicamentos , Moçambique , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Tripanossomíase Africana/tratamento farmacológico
8.
Exp Appl Acarol ; 74(1): 117-122, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29380168

RESUMO

Livestock constitutes a fundamental asset for the livelihood of rural communities in Angola. Rhipicephalus microplus (Acarina, Ixodidae) is considered to be the most important external parasite impacting the cattle industry in the world. The present work used a cross-sectional study on tick species infesting cattle in smallholder and commercial farms, to investigate the presence of R. microplus in Angola. This species was found to be recently established in certain areas of Cuanza-Sul and Benguela provinces. Furthermore, taking the current understanding of the pattern of dispersal of R. microplus into account, it is probable that this species is already present in other areas of the country. Animal movement without the necessary control measures facilitates the dispersal of this tick species. Consequently, R. microplus is causing rapid displacement of the native tick species, Rhipicephalus decoloratus. The presence of R. microplus in Angola constitutes a serious problem and poses a potential threat to the livestock sector as well as being an important risk factor for the sustainability of the livelihood strategies developed by smallholders.


Assuntos
Distribuição Animal , Doenças dos Bovinos/epidemiologia , Rhipicephalus/fisiologia , Infestações por Carrapato/veterinária , Angola/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Estudos Transversais , Feminino , Masculino , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
9.
Exp Appl Acarol ; 73(1): 91-102, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28856544

RESUMO

Ticks are ectoparasites that can act as vectors of a large number of pathogens in wild and domestic animals, pets, and occasionally humans. The global threat of emerging or re-emerging tick-borne diseases supports the need for research focused in the zoonotic transmission, especially in countries like Mozambique where rural populations are in close contact with domestic animals. The present study aims to: (1) identify tick species infesting cattle from Monapo and Nacala Porto, districts of Nampula province, Mozambique; and (2) investigate the presence of pathogens in the collected ticks. A total of 646 ticks were collected from cattle and morphologically identified as Amblyomma variegatum, Rhipicephalus microplus, and R. evertsi evertsi. For convenience, 72 A. variegatum and 15 R. microplus from Monapo, and 30 A. variegatum from Nacala Porto were screened for the presence of the selected pathogens: Rickettsia spp. (A. variegatum), and Babesia/Theileria spp. and Anaplasma/Ehrlichia spp. (R. microplus). Rickettsia africae was detected in four of the 72 A. variegatum collected in Monapo (5.6%). Additionally, one R. microplus tick (6.7%) was positive for Theileria velifera, one positive for Colpodella spp., one positive for Candidatus Midichloria mitochondrii, and another one positive for Anaplasma ovis. Using the present approach, no microorganisms were detected in tick samples from Nacala Porto. These findings expand our knowledge about the repertoire of tick-borne microorganisms in ticks in Nampula province, Mozambique.


Assuntos
Doenças dos Bovinos/epidemiologia , Ixodidae/microbiologia , Ixodidae/parasitologia , Infestações por Carrapato/veterinária , Anaplasma/isolamento & purificação , Animais , Babesia/isolamento & purificação , Bovinos , Doenças dos Bovinos/parasitologia , Ehrlichia/isolamento & purificação , Ixodidae/classificação , Ixodidae/fisiologia , Moçambique/epidemiologia , Rickettsia/isolamento & purificação , Theileria/isolamento & purificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/veterinária
10.
Int J Life Cycle Assess ; 22(6): 972-985, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32063683

RESUMO

PURPOSE: Although the impact of road pavement surface condition on rolling resistance has been included in the life cycle assessment (LCA) framework of several studies in the last years, there is still a high level of uncertainty concerning the methodological assumptions and the parameters that can affect the results. In order to adopt pavement carbon footprint/LCA as a decision-making tool, it is necessary to explore the impact of the chosen methods and assumptions on the LCA results. METHODS: This paper provides a review of the main models describing the impact of the pavement surface properties on vehicle fuel consumption and analyses the influence of the methodological assumptions related to the rolling resistance on the LCA results. It compares the CO2 emissions, calculated with two different rolling resistance models existing in literature, and performs a sensitivity test on some specific input variables (pavement deterioration rate, traffic growth, and emission factors/fuel efficiency improvement). RESULTS AND DISCUSSION: The model used to calculate the impact of the pavement surface condition on fuel consumption significantly affects the LCA results. The pavement deterioration rate influences the calculation in both models, while traffic growth and fuel efficiency improvement have a limited impact on the vehicle CO2 emissions resulting from the pavement condition contribution to rolling resistance. CONCLUSIONS AND RECOMMENDATIONS: Existing models linking pavement condition to rolling resistance and hence vehicle emissions are not broadly applicable to the use phase of road pavement LCA and further research is necessary before a widely-used methodology can be defined. The methods of modelling and the methodological assumptions need to be transparent in the analysis of the impact of the pavement surface condition on fuel consumption, in order to be interpreted by decision makers and implemented in an LCA framework. This will be necessary before product category rules (PCR) for pavement LCA can be extended to include the use phase.

11.
Emerg Infect Dis ; 22(12): 2165-2167, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27869589

RESUMO

In early 2014, abortions and death of ruminants were reported on farms in Maputo and Gaza Provinces, Mozambique. Serologic analysis and quantitative and conventional reverse transcription PCR confirmed the presence of Rift Valley fever virus. The viruses belonged to lineage C, which is prevalent among Rift Valley fever viruses in southern Africa.


Assuntos
Gado/virologia , Febre do Vale de Rift/epidemiologia , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift , Animais , Anticorpos Antivirais , Surtos de Doenças , Cabras , Humanos , Moçambique/epidemiologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/classificação , Vírus da Febre do Vale do Rift/genética , Vírus da Febre do Vale do Rift/imunologia , Vírus da Febre do Vale do Rift/isolamento & purificação , Estudos Soroepidemiológicos , Testes Sorológicos , Ovinos
12.
J Microencapsul ; 33(4): 391-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27530524

RESUMO

Drug delivery to corneal epithelial cells is challenging due to the intrinsic mechanisms that protect the eye. Here, we report a novel liposomal formulation to encapsulate and deliver a short sequence peptide into human corneal epithelial cells (hTCEpi). Using a mixture of Phosphatidylcholine/Caproylamine/Dioleoylphosphatidylethanolamine (PC/CAP/DOPE), we encapsulated a fluorescent peptide, resulting in anionic liposomes with an average size of 138.8 ± 34 nm and a charge of -18.2 ± 1.3 mV. After 2 h incubation with the peptide-encapsulated liposomes, 66% of corneal epithelial (hTCEpi) cells internalised the FITC-labelled peptide, demonstrating the ability of this formulation to effectively deliver peptide to hTCEpi cells. Additionally, lipoplexes (liposomes complexed with plasmid DNA) were also able to transfect hTCEpi cells, albeit at a modest level (8% of the cells). Here, we describe this novel anionic liposomal formulation intended to enhance the delivery of small cargo molecules in situ.


Assuntos
DNA Complementar , Epitélio Corneano/metabolismo , Peptídeos , Transfecção/métodos , Células Cultivadas , DNA Complementar/química , DNA Complementar/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Epitélio Corneano/citologia , Humanos , Lipossomos , Peptídeos/química , Peptídeos/farmacologia , Plasmídeos/química , Plasmídeos/farmacologia
13.
Curr Top Microbiol Immunol ; 366: 73-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22820706

RESUMO

Among the many challenges to health, infectious diseases stand out for their ability to have a profound impact on humans and animals. The recent years have witnessed an increasing number of novel infectious diseases. The numerous examples of infections which originated from animals suggest that the zoonotic pool is an important and potentially rich source of emerging diseases. Since emergence and re-emergence of pathogens, and particularly zoonotic agents, occur at unpredictable rates in animal and human populations, infectious diseases will constitute a significant challenge for the public health and animal health communities in the twenty-first century. The African continent suffers from one of the highest burdens of infectious diseases of humans and animals in the world but has the least capacity for their detection, identification and monitoring. Lessons learnt from recent zoonotic epidemics in Africa and elsewhere clearly indicate the need for coordinated research, interdisciplinary centres, response systems and infrastructures, integrated surveillance systems and workforce development strategies. More and stronger partnerships across national and international sectors (human health, animal health, environment) and disciplines (natural and social sciences) involving public, academic and private organisations and institutions will be required to meet the present and future challenges of infectious diseases. In order to strengthen the efficiency of early warning systems, monitoring trends and disease prediction and timely outbreak interventions for the benefit of the national and international community, it is essential that each nation improves its own capacity in disease recognition and laboratory competence. The SACIDS, a One Health African initiative linking southern African academic and research institutions in smart partnership with centres of science excellence in industrialised countries as well as international research centres, strives to strengthen Africa's capacity to detect, identify and monitor infectious diseases of humans and animals, to better manage health and socio-economic risks posed by them, and to improve research capacity in investigating the biologic, socio-economic, ecologic and anthropogenic factors responsible for emergence and re-emergence of infectious diseases.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Emergentes/prevenção & controle , Saúde Global , Zoonoses/prevenção & controle , Animais , Comportamento Cooperativo , Surtos de Doenças/prevenção & controle , Abastecimento de Alimentos , Humanos , África do Sul
14.
Onderstepoort J Vet Res ; 91(1): e1-e8, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38708768

RESUMO

Interface areas shared by humans, domestic and wild animals may serve as high transmission contexts for Toxoplasma gondii. However, knowledge about the epidemiology of T. gondii in such areas is currently limited. The present study assessed the seroprevalence of T. gondii in different hosts from Mpumalanga, South Africa. Furthermore, we investigated the local knowledge and related practices about T. gondii by conducting a questionnaire study in the community. Blood samples were obtained and analysed for T. gondii antibodies using a commercial multispecies latex agglutination kit. The seroprevalence detected in humans (n = 160; patients showing signs of acute febrile illness), cats (n = 9), chickens (n = 336) and goats (n = 358) was 8.8%, 0.0%, 4.2% and 11.2%, respectively. Seroprevalence in impalas (n = 97), kudus (n = 55), wild dogs (n = 54), wildebeests (n = 43), warthogs (n = 97) and zebras (n = 68) was calculated at 5.2%, 7.3%, 100.0%, 20.9%, 13.4% and 9.1%, respectively. The questionnaire revealed that 63.0% of household owners were subsistence farmers, and 35.9% were pet owners. A high level of female participation was found (75.3%) when compared to male participation (24.7%). The results show a low circulation of T. gondii in the domestic cycle and suggest the presence of possible bridges between the wildlife cycle and the surrounding domestic cycle.Contribution: The study contributes to identifying transmission patterns and risk factors of T. gondii within human and animal populations. This topic fits within the scope of the journal presenting original research in veterinary science, with the focus on wild and domestic populations on the African continent on a topic of universal importance.


Assuntos
Animais Selvagens , Toxoplasma , Toxoplasmose Animal , Animais , África do Sul/epidemiologia , Humanos , Estudos Soroepidemiológicos , Toxoplasmose Animal/epidemiologia , Feminino , Masculino , Toxoplasmose/epidemiologia , Gatos , Gado/parasitologia , Anticorpos Antiprotozoários/sangue , Zoonoses , Cabras , Inquéritos e Questionários
15.
MethodsX ; 13: 102815, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39040215

RESUMO

Radon gas (Rn-222) in water poses health risks due to radiation exposure, yet it's also an important tracer for studying natural systems. Sampling procedures for Rn-222 analysis are very sensitive to potential losses of the gas to the atmosphere. It requires a well-defined and properly validated protocol to ensure accuracy and reliability. A novel sampler was developed to collect surface water from a distance (e.g. from bridges), addressing logistic challenges posed by topography. The sampler, manually operated, ensures precise depth-specific sampling throughout the water column. A three-stage validation process (technical performance test, uncertainty estimations and preliminary test) was followed to validate the protocol.•The comparison of the technical procedure for analysis and measurement through Liquid Scintillation Counting is statistically robust (one-way ANOVA p-value = 0.96).•For the protocol proposed for Rn-222 determination, the estimated sampling and measurement uncertainties (k = 2) are respectively 5% and 15%. These are compatible with the literature and the laboratory's precision.•Preliminary tests, with meaningful patterns identified and possibly related to the river's hydrodynamics, revealed a very reliable protocol, even in low Rn-222 concentrations.Therefore, the sampler has demonstrated a good analytical reproducibility and was considered validated for Rn-222 determination in surface waters.

16.
BMC Ecol Evol ; 24(1): 29, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433185

RESUMO

The African buffalo, Syncerus caffer, is a key species in African ecosystems. Like other large herbivores, it plays a fundamental role in its habitat acting as an ecosystem engineer. Over the last few centuries, African buffalo populations have declined because of range contraction and demographic decline caused by direct or indirect human activities. In Mozambique, historically home to large buffalo herds, the combined effect of colonialism and subsequent civil wars has created a critical situation that urgently needs to be addressed. In this study, we focused on the analysis of genetic diversity of Syncerus caffer caffer populations from six areas of Mozambique. Using genome-wide SNPs obtained from ddRAD sequencing, we examined the population structure across the country, estimated gene flow between areas under conservation management, including national reserves, and assessed the inbreeding coefficients. Our results indicate that all studied populations of Syncerus caffer caffer are genetically depauperate, with a high level of inbreeding. Moreover, buffaloes in Mozambique present a significant population differentiation between southern and central areas. We found an unexpected genotype in the Gorongosa National Park, where buffaloes experienced a dramatic population size reduction, that shares a common ancestry with southern populations of Catuane and Namaacha. This could suggest the past occurrence of a connection between southern and central Mozambique and that the observed population structuring could reflect recent events of anthropogenic origin. All the populations analysed showed high levels of homozygosity, likely due to extensive inbreeding over the last few decades, which could have increased the frequency of recessive deleterious alleles. Improving the resilience of Syncerus caffer caffer in Mozambique is essential for preserving the ecosystem integrity. The most viable approach appears to be facilitating translocations and re-establishing connectivity between isolated herds. However, our results also highlight the importance of assessing intraspecific genetic diversity when considering interventions aimed at enhancing population viability such as selecting suitable source populations.


Assuntos
Bison , Búfalos , Humanos , Animais , Búfalos/genética , Ecossistema , Endogamia , Moçambique
17.
Microorganisms ; 12(8)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39203504

RESUMO

Tick-borne rickettsioses are considered among the oldest known vector-borne zoonotic diseases. Among the rickettsiae, Rickettsia africae is the most reported and important in Africa, as it is the aetiological agent of African tick bite fever (ATBF). Studies describing the prevalence of R. africae in southern Africa are fragmented, as they are limited to small geographical areas and focused on Amblyomma hebraeum and Amblyomma variegatum as vectors. Amblyomma spp. ticks were collected in Angola, Mozambique, South Africa, Zambia and Zimbabwe during the sampling period from March 2020 to September 2022. Rickettsia africae was detected using the ompA gene, while characterisation was conducted using omp, ompA, ompB and gltA genes. In total, 7734 Amblyomma spp. ticks were collected and were morphologically and molecularly identified as Amblyomma eburneum, A. hebraeum, Amblyomma pomposum and A. variegatum. Low levels of variability were observed in the phylogenetic analysis of the R. africae concatenated genes. The prevalence of R. africae ranged from 11.7% in South Africa to 35.7% in Zambia. This is one of the largest studies on R. africae prevalence in southern Africa and highlights the need for the inclusion of ATBF as a differential diagnosis when inhabitants and travellers present with flu-like symptoms in the documented countries.

18.
Parasit Vectors ; 17(1): 364, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198812

RESUMO

BACKGROUND: Amblyomma spp. ticks, known for their long mouthparts, bright ornate appearance and aggressive hunting behaviour, are vectors of a number of important pathogens. In southern Africa, 17 Amblyomma spp. are currently documented. Of these species, Amblyomma hebraeum and Amblyomma variegatum have been well studied due to their wide geographical range and their status as competent vectors of pathogens that are of veterinary and medical importance. Studies on other Amblyomma spp. in southern Africa have been neglected, fostering ongoing debates on the validity of certain species such as Amblyomma pomposum. This study investigated the inter- and intra-species variation of Amblyomma ticks collected in southern Africa, focusing on resolving the dispute about A. pomposum and A. variegatum being distinct species. METHODS: Four Amblyomma tick species were collected from Angola, Mozambique, South Africa, Zambia and Zimbabwe, and were identified morphologically as Amblyomma eburneum (208), A. hebraeum (4758), A. pomposum (191) and A. variegatum (2577) using identification keys. Gene amplification targeting the 12S and 16S rRNA, cytochrome oxidase I, cytochrome B and internal transcribed spacer-2 genes was conducted for 204 ticks, for which varying success was achieved during amplification for each of the markers. Maximum likelihood analyses were performed in IQ-TREE. RESULTS: The phylogenetic topologies and ABGD analyses of each individual gene clustered A. pomposum within the A. variegatum clade, while clearly separating A. eburneum and A. hebraeum from all other species. None of the genetic markers indicated intraspecific structuring on the basis of geographical origin, despite great distances between sampling sites. CONCLUSION: Our study concludes that there is insufficient molecular evidence to differentiate A. pomposum and A. variegatum from each other. We highlight the need for whole mitochondrial genome sequencing of these two species to resolve the ongoing controversies. Furthermore, we propose mating and hybrid viability studies between the two species to confirm their reproductive isolation.


Assuntos
Amblyomma , Variação Genética , Filogenia , Animais , Amblyomma/genética , Amblyomma/classificação , Amblyomma/anatomia & histologia , África Austral , Feminino , África do Sul , Masculino , Moçambique , Análise de Sequência de DNA
19.
Ticks Tick Borne Dis ; 15(6): 102387, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39116621

RESUMO

Migratory birds play an important role in transporting ixodid ticks and tick-borne pathogens between continents. During the Boreal spring, migratory birds reach Europe, mainly from sub-Saharan Africa or from northern African countries but not much is known about the diversity and ecology of the ticks they spread. From 2017 to 2022, in the framework of two consecutive projects focused on sampling migratory birds from Africa to Europe, a total of 27 immature Amblyomma ticks were collected from migratory birds, belonging to 8 species, captured on the Island of Ventotene, an important stop-over site in the Mediterranean Sea. In the absence of adult specimens, morphological identification was limited to assigning these ticks to the Amblyomma genus. In this study, sequencing and comparative analysis of three mitochondrial molecular markers (12S rDNA, 16S rDNA, COI) were performed to achieve taxonomic identification. Sequences obtained from Ventotene specimens matched at 100% identity with Amblyomma sparsum. In conclusion, this study documented that immature stages of this species belonging to the Amblyomma marmoreum complex reached the Pontine Islands for six consecutive years. The entry of alien tick species and their potentially transmitted pathogens deserves further study, also in light of the globally ongoing climate change.

20.
Nanotechnology ; 24(37): 375104, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23975064

RESUMO

This paper focuses on the targeting of single-walled carbon nanotubes (SWNTs) for the treatment of breast cancer with minimal side effects using photothermal therapy. The human protein annexin V (AV) binds specifically to anionic phospholipids expressed externally on the surface of tumour cells and endothelial cells that line the tumour vasculature. A 2 h incubation of the SWNT-AV conjugate with proliferating endothelial cells followed by washing and near-infrared (NIR) irradiation at a wavelength of 980 nm was enough to induce significant cell death; there was no significant cell death with irradiation or the conjugate alone. Administration of the same conjugate i.v. in BALB/c female mice with implanted 4T1 murine mammary at a dose of 0.8 mg SWNT kg(-1) and followed one day later by NIR irradiation of the tumour at a wavelength of 980 nm led to complete disappearance of implanted 4T1 mouse mammary tumours for the majority of the animals by 11 days since the irradiation. The combination of the photothermal therapy with the immunoadjuvant cyclophosphamide resulted in increased survival. The in vivo results suggest the SWNT-AV/NIR treatment is a promising approach to treat breast cancer.


Assuntos
Hipertermia Induzida , Neoplasias Mamárias Animais/terapia , Nanotubos de Carbono/química , Fototerapia , Animais , Anexina A5/isolamento & purificação , Anexina A5/metabolismo , Biotinilação , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Fluoresceína-5-Isotiocianato/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Maleimidas/química , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Força Atômica , Microscopia de Fluorescência , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Proteínas Recombinantes/isolamento & purificação , Espectroscopia de Luz Próxima ao Infravermelho , Coloração e Rotulagem , Suspensões
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