Refinar búsqueda
Resultados 401-410 de 586
Towards One Health disease surveillance: The Southern African Centre for Infectious Disease Surveillance approach Texto completo
2012
Esron D. Karimuribo | Kuya Sayalel | Eric Beda | Nick Short | Philemon Wambura | Leonard G. Mboera | Lughano J.M. Kusiluka | Mark M. Rweyemamu
Towards One Health disease surveillance: The Southern African Centre for Infectious Disease Surveillance approach Texto completo
2012
Esron D. Karimuribo | Kuya Sayalel | Eric Beda | Nick Short | Philemon Wambura | Leonard G. Mboera | Lughano J.M. Kusiluka | Mark M. Rweyemamu
Africa has the highest burden of infectious diseases in the world and yet the least capacity for its risk management. It has therefore become increasingly important to search for ‘fit-for- purpose’ approaches to infectious disease surveillance and thereby targeted disease control. The fact that the majority of human infectious diseases are originally of animal origin means we have to consider One Health (OH) approaches which require inter-sectoral collaboration for custom-made infectious disease surveillance in the endemic settings of Africa. A baseline survey was conducted to assess the current status and performance of human and animal health surveillance systems and subsequently a strategy towards OH surveillance system was developed. The strategy focused on assessing the combination of participatory epidemiological approaches and the deployment of mobile technologies to enhance the effectiveness of disease alerts and surveillance at the point of occurrence, which often lies in remote areas. We selected three study sites, namely the Ngorongoro, Kagera River basin and Zambezi River basin ecosystems. We have piloted and introduced the next-generation Android mobile phones running the EpiCollect application developed by Imperial College to aid geo-spatial and clinical data capture and transmission of this data from the field to the remote Information Technology (IT) servers at the research hubs for storage, analysis, feedback and reporting. We expect that the combination of participatory epidemiology and technology will significantly improve OH disease surveillance in southern Africa.
Mostrar más [+] Menos [-]Towards One Health disease surveillance: The Southern African Centre for Infectious Disease Surveillance approach Texto completo
2012
Karimuribo, Esron D.(Southern African Centre for Infectious Disease Surveillance) | Sayalel, Kuya(Ngorongoro Conservation Area Authority) | Beda, Eric(Southern African Centre for Infectious Disease Surveillance) | Short, Nick(Royal Veterinary College) | Wambura, Philemon(Southern African Centre for Infectious Disease Surveillance) | Mboera, Leonard G.(National Institute for Medical Research) | Kusiluka, Lughano J.M.(The Open University of Tanzania) | Rweyemamu, Mark M.(Southern African Centre for Infectious Disease Surveillance)
Africa has the highest burden of infectious diseases in the world and yet the least capacity for its risk management. It has therefore become increasingly important to search for 'fit-for-purpose' approaches to infectious disease surveillance and thereby targeted disease control. The fact that the majority of human infectious diseases are originally of animal origin means we have to consider One Health (OH) approaches which require inter-sectoral collaboration for custom-made infectious disease surveillance in the endemic settings of Africa. A baseline survey was conducted to assess the current status and performance of human and animal health surveillance systems and subsequently a strategy towards OH surveillance system was developed. The strategy focused on assessing the combination of participatory epidemiological approaches and the deployment of mobile technologies to enhance the effectiveness of disease alerts and surveillance at the point of occurrence, which often lies in remote areas. We selected three study sites, namely the Ngorongoro, Kagera River basin and Zambezi River basin ecosystems. We have piloted and introduced the next-generation Android mobile phones running the EpiCollect application developed by Imperial College to aid geo-spatial and clinical data capture and transmission of this data from the field to the remote Information Technology (IT) servers at the research hubs for storage, analysis, feedback and reporting. We expect that the combination of participatory epidemiology and technology will significantly improve OH disease surveillance in southern Africa.
Mostrar más [+] Menos [-]Natural hosts of the larvae of <i>Nuttalliella</i> sp. (<i>N. namaqua</i>?) (Acari: Nuttalliellidae) Texto completo
2012
Ivan G. Horak | Heike Lutermann | Katarina Medger | Dmitry A. Apanaskevich | Conrad A. Matthee
The first collection of unengorged and fully engorged larvae of Nuttalliella sp. (N. namaqua?) from the murid rodents Micaelamys namaquensis, Aethomys chrysophilus and Acomys spinosissimus in Limpopo Province and from M. namaquensis in the Northern Cape Province, South Africa, is documented. A total of nine larvae were collected from two M. namaquensis in the Soutpansberg mountain range in the Limpopo Province during April 2009. During the last week of September 2011, 221 larvae were collected from rodents at the same locality and 10 of 48 M. namaquensis, 6 of 12 Ae. chrysophilus and 3 of 14 Ac. spinosissimus were infested. One of the M. namaquensis harboured 53 larvae. Five larvae were collected from two M. namaquensis in the Northern Cape Province. Total genomic DNA was extracted from two larvae and a region of the 18S rRNA gene was sequenced for these. BLASTn searches revealed similarity between these specimens and the Nuttalliella sequences published on GenBank.
Mostrar más [+] Menos [-]Epidemiological aspects of bovine trypanosomosis in an endemic focus of eastern Zambia: The role of trypanosome strain variability in disease pattern Texto completo
2012
Justin Masumu | G. Tshilenge | V. Mbao
Epidemiological aspects of bovine trypanosomosis in an endemic focus of eastern Zambia: The role of trypanosome strain variability in disease pattern Texto completo
2012
Justin Masumu | G. Tshilenge | V. Mbao
Bovine trypanosomosis displays various epidemiological aspects in various areas. In some instances the disease has a high prevalence in animals with high impact on production whereas in other cases the disease has a low impact on production despite a high level of infection in animals. In addition epidemiological changes are frequently observed in various areas and are related to many factors including the vectors, the host, the parasites, the environment as well as the livestock management. However the implication of these factors in these changes is not fully elucidated. In eastern Zambia, factors predicting the establishment of severe infection in cattle are all present. However trypanosomosis occurring in cattle in this area has a low impact on livestock production. Several studies on the characterisation of trypanosome strains circulating in domestic and wild animals have been conducted in order to clarify the epidemiology of this disease in this area. These studies aimed at evaluating genetic and biological characteristics of these strains including their virulence profiles, their transmissibility by tsetse flies, their resistance to drugs and interference between different strains. In this review these findings are analysed in order to elucidate the implication of trypanosome strain variability in the distribution and the expression of this disease in the study area. The evolutionary trends of the situation occurring in this study area are also explained. Use of these findings is the context of disease control in the study area is further discussed.
Mostrar más [+] Menos [-]Epidemiological aspects of bovine trypanosomosis in an endemic focus of eastern Zambia: The role of trypanosome strain variability in disease pattern Texto completo
2012
Masumu, Justin(Southern African Centre for Infectious Disease Surveillance) | Tshilenge, G.(Southern African Centre for Infectious Disease Surveillance) | Mbao, V.(Centre for Ticks and Tick-borne Diseases)
Bovine trypanosomosis displays various epidemiological aspects in various areas. In some instances the disease has a high prevalence in animals with high impact on production whereas in other cases the disease has a low impact on production despite a high level of infection in animals. In addition epidemiological changes are frequently observed in various areas and are related to many factors including the vectors, the host, the parasites, the environment as well as the livestock management. However the implication of these factors in these changes is not fully elucidated. In eastern Zambia, factors predicting the establishment of severe infection in cattle are all present. However trypanosomosis occurring in cattle in this area has a low impact on livestock production. Several studies on the characterisation of trypanosome strains circulating in domestic and wild animals have been conducted in order to clarify the epidemiology of this disease in this area. These studies aimed at evaluating genetic and biological characteristics of these strains including their virulence profiles, their transmissibility by tsetse flies, their resistance to drugs and interference between different strains. In this review these findings are analysed in order to elucidate the implication of trypanosome strain variability in the distribution and the expression of this disease in the study area. The evolutionary trends of the situation occurring in this study area are also explained. Use of these findings is the context of disease control in the study area is further discussed.
Mostrar más [+] Menos [-]<i>Bartonella henselae</i> and <i>Bartonella quintana</i> seroprevalence in HIV-positive, HIV-negative and clinically healthy volunteers in Gauteng, South Africa Texto completo
2012
Anastasia N. Trataris | Lorraine Arntzen | Jennifer Rossouw | John Frean | Allan Karstaedt
Bartonella is a genus of opportunistic, Gram-negative bacilli transmitted from animals to human hosts. Bartonellae are newly emerging pathogens that can cause a variety of clinical manifestations in both immunocompromised and healthy persons. The aims were to determine the IgG and IgM seroprevalences of Bartonella henselae and Bartonella quintana in immunocompromised and immunocompetent individuals using an immunofluorescence assay (IFA). A total of 382 HIV-positive outpatients of the Chris Hani Baragwanth HIV-clinic, 382 retrospective residual samples from HIV-negative antenatal patients, and 42 clinically healthy volunteers were tested using a commercially available IFA kit to determine the prevalence of IgG and IgM antibodies to B. henselae and B. quintana. The IgM and IgG seroprevalences for the HIV-positive patients were 14% (53/382) and 32% (121/382), respectively, compared to 18% for both IgM (62/342) and IgG (63/342) in the HIV- negative antenatal patients. Similarly, the prevalence for IgM was 17% (7/42) and IgG was 19% (8/42) for the clinically healthy volunteers. HIV-positivity appears to be a significant risk factor for Bartonella infection, compared with healthy subjects. Although IFAs have a high sensitivity for Bartonella antibody detection, they have various limitations including cross-reactivity with other closely-related human pathogens.
Mostrar más [+] Menos [-]Acknowledgement to reviewers Texto completo
2012
Editorial Office
Detection of <i>Haemophilus parasuis</i> isolates from South China by loop-mediated isothermal amplification and isolate characterisation Texto completo
2012
Jian-min Zhang | Hai-yan Shen | Ming Liao | Tao Ren | Li-li Guo | Cheng-gang Xu | Sai-xiang Feng | Hui-ying Fan | Jing-yi Li | Ji-dang Chen | Bin Zhang
Haemophilus parasuis is the etiological agent of Glässer’s disease, which is characterised by fibrinous polyserositis, meningitis and polyarthritis, causing severe economic losses to the swine industry. In this study, a loop-mediated isothermal amplification (LAMP) test was developed to improve the specificity, facility and speed of diagnosis of H. parasuis isolates. The LAMP assay rapidly amplified the target gene within 50 min incubation at 63 °C in a laboratory water bath. The LAMP amplicon could be visualised directly in the reaction tubes following the addition of SYBR Green I dye. The detection limit of this LAMP method was 10 CFU/mL, which was 10 times more sensitive than the earlier 16S rRNA polymerase chain reaction (PCR) test conducted by Oliveira, Galina and Pijoan (2001), and no cross-reactivity was observed from other non-H. parasuis strains. This LAMP test was evaluated further on 187 clinical specimens from pigs suspected of being infected with H. parasuis. Forty-three were found positive by bacterial isolation of H. parasuis, as well as by the 16S rRNA PCR and LAMP tests. The 43 H. parasuis isolates were classified into 9 serovars and had 37 genetic patterns when analysed by pulsed-field gel electrophoresis (PFGE). This displayed that various H. parasuis serovars and genotypes were widely distributed in South China. Therefore, the speed, specificity and sensitivity of the LAMP test, the lack of a need for expensive equipment, and the visual readout showed great potential for a correct clinical diagnosis of H. parasuis in favour of controlling Glässer’s disease.
Mostrar más [+] Menos [-]A questionnaire survey of poultry layer farmers in Khartoum State, Sudan, to study their antimicrobial awareness and usage patterns Texto completo
2012
Mohamed M. Sirdar | Jackie Picard | Shahn Bisschop | Bruce Gummow
A questionnaire survey of poultry layer farmers in Khartoum State, Sudan, to study their antimicrobial awareness and usage patterns Texto completo
2012
Mohamed M. Sirdar | Jackie Picard | Shahn Bisschop | Bruce Gummow
An initial census of layer farms in Khartoum State, Sudan, was carried out in late 2007 and early 2008 and found that there were 252 layer farms with a total population of 2 221 800 birds. This paper reports the findings of the census. Based on this information, a structured questionnaire survey of 92 farms was then conducted in the state in April 2008 to collect data on antibiotic usage, demographic data and public health awareness. Ninety-eight per cent of participating farms comprised open-sided houses. It was found that 49% of the farms surveyed were on antibiotic treatment when the survey was conducted, whilst 59% of the farms had used antibiotics within the last 3 months. The study found that farmers and producers had a lack of knowledge about antimicrobial residues, their withdrawal periods and the risk posed by the consumption of these residues. The study also concluded that traditional farming systems in Sudan relied heavily on antimicrobial medication to control disease and almost half of the farms surveyed were treating their flocks with antimicrobials. In addition to this, there was a lack of disease control programmes which probably resulted in a massive use of antibiotics to control endemic diseases. This was further compounded by the absence of governmental supervision and control on the use of drugs.
Mostrar más [+] Menos [-]New technologies to diagnose and monitor infectious diseases of livestock: Challenges for sub-Saharan Africa Texto completo
2012
Donald P. King | Miki Madi | Valerie Mioulet | Jemma Wadsworth | Caroline F. Wright | Begoña Valdazo-González | Nigel P. Ferris | Nick J. Knowles | Jef Hammond
New technologies to diagnose and monitor infectious diseases of livestock: Challenges for sub-Saharan Africa Texto completo
2012
Donald P. King | Miki Madi | Valerie Mioulet | Jemma Wadsworth | Caroline F. Wright | Begoña Valdazo-González | Nigel P. Ferris | Nick J. Knowles | Jef Hammond
Using foot-and-mouth disease (FMD) as an example, this review describes new tools that can be used to detect and characterise livestock diseases. In recent years, molecular tests that can detect and characterise pathogens in a diverse range of sample types have revolutionised laboratory diagnostics. In addition to use in centralised laboratories, there are opportunities to locate diagnostic technologies close to the animals with suspected clinical signs. Work in this area has developed simple-to-use lateral-flow devices for the detection of FMD virus (FMDV), as well as new hardware platforms to allow molecular testing to be deployed into the field for use by non-specialists. Once FMDV has been detected, nucleotide sequencing is used to compare field strains with reference viruses. Transboundary movements of FMDV are routinely monitored using VP1 sequence data, while higher resolution transmission trees (at the farm-to-farm level) can be reconstructed using full-genome sequencing approaches. New technologies such as next-generation sequencing technologies are now being applied to dissect the viral sequence populations that exist within single samples. The driving force for the use of these technologies has largely been influenced by the priorities of developed countries with FMD-free (without vaccination) status. However, it is important to recognise that these approaches also show considerable promise for use in countries where FMD is endemic, although further modifications (such as sample archiving and strain and serotype characterisation) may be required to tailor these tests for use in these regions. Access to these new diagnostic and sequencing technologies in sub-Saharan Africa have the potential to provide novel insights into FMD epidemiology and will impact upon improved strategies for disease control. Effective control of infectious diseases is reliant upon accurate diagnosis of clinical cases using laboratory tests, together with an understanding of factors that impact upon the epidemiology of the infectious agent. A wide range of new diagnostic tools and nucleotide sequencing methods are used by international reference laboratories to detect and characterise the agents causing outbreaks of infectious diseases. In the past, high costs (initial capital expenses, as well as day-to-day maintenance and running costs) and complexity of the protocols used to perform some of these tests have limited the use of these methods in smaller laboratories. However, simpler and more cost-effective formats are now being developed that offer the prospect that these technologies will be even more widely deployed into laboratories particularly those in developing regions of the world such as sub-Saharan Africa.
Mostrar más [+] Menos [-]New technologies to diagnose and monitor infectious diseases of livestock: Challenges for sub-Saharan Africa Texto completo
2012
King, Donald P.(Institute for Animal Health) | Madi, Miki(Institute for Animal Health) | Mioulet, Valerie(Institute for Animal Health) | Wadsworth, Jemma(Institute for Animal Health) | Wright, Caroline F.(Institute for Animal Health) | Valdazo-González, Begoña(Institute for Animal Health) | Ferris, Nigel P.(Institute for Animal Health) | Knowles, Nick J.(Institute for Animal Health) | Hammond, Jef(Institute for Animal Health)
Using foot-and-mouth disease (FMD) as an example, this review describes new tools that can be used to detect and characterise livestock diseases. In recent years, molecular tests that can detect and characterise pathogens in a diverse range of sample types have revolutionised laboratory diagnostics. In addition to use in centralised laboratories, there are opportunities to locate diagnostic technologies close to the animals with suspected clinical signs. Work in this area has developed simple-to-use lateral-flow devices for the detection of FMD virus (FMDV), as well as new hardware platforms to allow molecular testing to be deployed into the field for use by non-specialists. Once FMDV has been detected, nucleotide sequencing is used to compare field strains with reference viruses. Transboundary movements of FMDV are routinely monitored using VP1 sequence data, while higher resolution transmission trees (at the farm-to-farm level) can be reconstructed using full-genome sequencing approaches. New technologies such as next-generation sequencing technologies are now being applied to dissect the viral sequence populations that exist within single samples. The driving force for the use of these technologies has largely been influenced by the priorities of developed countries with FMD-free (without vaccination) status. However, it is important to recognise that these approaches also show considerable promise for use in countries where FMD is endemic, although further modifications (such as sample archiving and strain and serotype characterisation) may be required to tailor these tests for use in these regions. Access to these new diagnostic and sequencing technologies in sub-Saharan Africa have the potential to provide novel insights into FMD epidemiology and will impact upon improved strategies for disease control. Effective control of infectious diseases is reliant upon accurate diagnosis of clinical cases using laboratory tests, together with an understanding of factors that impact upon the epidemiology of the infectious agent. A wide range of new diagnostic tools and nucleotide sequencing methods are used by international reference laboratories to detect and characterise the agents causing outbreaks of infectious diseases. In the past, high costs (initial capital expenses, as well as day-to-day maintenance and running costs) and complexity of the protocols used to perform some of these tests have limited the use of these methods in smaller laboratories. However, simpler and more cost-effective formats are now being developed that offer the prospect that these technologies will be even more widely deployed into laboratories particularly those in developing regions of the world such as sub-Saharan Africa.
Mostrar más [+] Menos [-]MSc: In One Health Molecular Biology Texto completo
2012
Philemon Wambura
Cysticercosis in the Democratic Republic Of Congo Texto completo
2012
P. Dorny | C. Kabwe | K. Kirezi | K. Lukanu | P. Lutumba | V. Maketa | P. Matondo | K. Polman | N. Praet | N. Speybroeck | J. Sumbu
Cysticercosis, caused by Taenia solium eggs, is a zoonotic disease whose consequences can be severe especially in the cerebral localisation (neuorcysticercosis). Indeed, neurocysticercosis is the first cause of epilepsy amongst the infectious etiology group. Following the increase of epilepsy cases in Kinshasa and Bas-Congo, it was important to assess the fraction attributable to neurocysticercosis especially as data on cysticercosis in Democratic Republic Of Congo (DRC) dating from 1970. A joint study between veterinary and human doctors was conducted in the provinces of Bas-Congo and Kinshasa between 2008 and 2010. Blood samples were collected from the general population, patients with epilepsy and pigs. These samples were analysed using ELISA antigen in the laboratory of the Institute of Tropical Medicine in Antwerp. Patients positive to ELISA antigen took the CT scan exam for the confirmation of neurocysticercosis. In the province of Kinshasa, of 530 epileptic patients, 6.3% were identified as neurocysticercosis cases. Out of a total of 498 pigs, 38.9% were positive for cysticercosis. In the province of Bas- Congo, of 943 inhabitants from Malanga village, 21.6% were positive with predominance in males (26.4% versus 17.5%). A total of 145 pigs from 5 villages were examined and 41.2% found positive. We can conclude that cysticercosis in the DRC has been neglected for a long time and cysticercosis could be a real major public health problem. Prospective studies addressing the consequences of cysticercosis in communities are needed in order to prevent epilepsy due to neurocysticercosis.
Mostrar más [+] Menos [-]