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One Health - ‘joining the dots’ Texto completo
2012
Hazel M. Dockrell
One Health - ‘joining the dots’
Mostrar más [+] Menos [-]Immunogeno: Protective mechanism for Rift Valley fever in the Democratic Republic of Congo Texto completo
2012
Georges Tshilenge
Rift Valley fever (RVF) is an acute, fever causing viral disease that affects domestic animals and humans. In Democratic Republic of Congo (DRC), this pathology is not well documented. No epidemic of the RVF has not been reported but sera samples collected in six provinces surveyed from 2005 to 2006 revealed 14% of apparent prevalence and, high apparent prevalence (20%) of antibodies against RVF virus was reported in Katanga Province during the same survey; this serological evidence was associated with abortions cases in Cattle (Mulumba et al. 2009). Livestock immunisation is important for control of Rift Valley fever virus (RVFV) epidemics; however immunisation of susceptible domestic animals in endemic countries does not protect animals against the clinical disease but prevents the propagation of virus to human population through reduction of the amplification degree in host animals. The humoral immunity is sufficient for protection for animals as well as for humans. The infection caused by RVFV leads to neutralisation of the immunity of the animal (Barnard 1979). Various immunological studies have been made on the characterisation of immune response during RVFV epidemics but, until now several studies have been concentrated on the response of the innate immune particularly based on signal interferon system than the response of the adaptive immune and cell mediated humoral immune. The available information on the immune response related to RVFV does not seem to provide enough information on various mechanisms of the response immune system. The aim of the study is based on mechanism of immune response system including protective effect of immunisation against RVFV. In addition, epidemiological and molecular studies will be assessed. As a matter of fact, following studies will be conducted: • evaluation of the immunological protection against Rift Valley fever in vaccinated and non- vaccinated cattle using IgG and IgM ELISAs in Katanga Province • assessment of cellular response to Rift Valley fever disease in vaccinated and naturally infected cattle • molecular characterisation of RVFV strains circulating in vaccinated and non vaccinated cattle • assessment of protective effect related to vaccinal strains in cattle, using a longitudinal survey. The studies will be carried out Northern Katanga Province within two areas, one with historyof circulation of RVFV and other without history RVFV circulation. Whole blood, spleen, liver, lymph node will be collected as target tissues from cattle carcasses. In addition, goats and sheeps samples will be collected alongside from each area in order to clarify the disease situation. Serological tests based on the detection of Ig M and Ig G will be used. DIVA tests, LAMP, and IHC techniques will be used. Within previously vaccinated areas in the above mentioned areas and those that are not vaccinated, the collected samples will be analysed using RT-PCR/RT-LAMP. In vitro experimental studies systems will be carried out using animal PMBCs that will be infected with wild type of RVF virus as well as with vaccinal strains, such as clones 13 and MP12 to characterise various cell types such as CD4 T cells, CD8 T cells, B-cells, NK cells and, macrophages will be studied with regard to activation and apoptosis signals on various post – infection days, using flow cytometry. A pool of animals will be vaccinated with the Clone 13 and another with the MP12 to determine the traceability. The monitoring of the immune response will be done through the measurement of immunoglobulin G (Ig G) and immunoglobulin M (Ig M). RT-PCR, spectrophotometer or Facs methods will be used for the dosage of cells T CD4 + and Cell T CD8+.
Mostrar más [+] Menos [-]Co-infections of malaria and soil-transmitted helminths in localities with different levels of urbanisation in the Mount Cameroon region Texto completo
2012
E. Lum | H.K. Kimbi | J. Mbuh | J. Ndamukong-Nyanga | A.L. Njunda | J. Lello
Malaria co-exists with intestinal helminths and they have different effects on infected individuals. A total of 235 and 208 children from Ekona and Great Soppo respectively of both sexes aged 4–14 years were enrolled into a cross-sectional study. Capillary blood was collected for detection and determination of malaria parasitaemia as well as PCV. Stool samples were collected for quantitative determination of helminth ova by Kato-Katz technique. The prevalence of malaria and helminths was higher in Ekona than Great Soppo. In Great Soppo, Trichuris was the most prevalent helminth than Great Soppo and an association was found between these co-infections. More children were co-infected in Ekona and co-infecting species were Ascaris and Plasmodium falciparum. The prevalence of malaria and intestinal helminths as well as co-infection was lower in Great Soppo than in Ekona, probably due to increased urbanization in Great Soppo than Ekona.
Mostrar más [+] Menos [-]A foresight vision for infectious diseases in Africa Texto completo
2012
Joe Brownlie
A foresight vision for infectious diseases in Africa
Mostrar más [+] Menos [-]Acknowledgements Texto completo
2012
Antony Musoke
The work in the papers and abstracts was supported by Wellcome Trust Grant WT087546MA to the Southern African Centre for Infectious Disease Surveillance (http://www.sacids.org) and its collaborating UK partner institutions, namely the London School of Hygiene and Tropical Medicine (http://www.lshtm.ac.uk), the Royal Veterinary College (http://www.rvc.ac.uk) and the London International Development Centre (http://www.lidc.org.uk). The work presented by Esron Karimuribo et al. was supported by Rockefeller Foundation.
Mostrar más [+] Menos [-]Economic benefits or drivers of a ‘One Health’ approach: Why should anyone invest? Texto completo
2012
Jonathan Rushton | Barbara Häsler | Nicoline de Haan | Ruth Rushton
One Health concepts and ideas are some of the oldest in the health discipline, yet they have not become main stream. Recent discussions of the need for One Health approaches require some reflection on how to present a case for greater investments. The paper approaches this problem from the perspective of the control and management of resources for health in general. It poses the following questions, (1) where do we need extra resources for One Health, (2) where can we save resources through a One Health approach and (3) who has control of the resources that do exist for One Health? In answering these questions three broad areas are explored, (1) The management and resources allocated for diseases, (2) The isolation of parts of the society that require human and animal health services and (3) The use of resources and skills that are easily transferable between human and animal health. The paper concludes that One Health approaches are applicable in many scenarios. However, the costs of getting people from different disciplines to work together in order to achieve a true One Health approach can be large. To generate tangible benefits requires careful management of specialist skills, knowledge and equipment, which can only be achieved by a greater openness of the human and animal health disciplines. Without this openness, policy makers will continue to doubt the real value of One Health. In summary the future success of One Health is about people working in the research, education and provision of health systems around the world embracing and managing change more effectively.
Mostrar más [+] Menos [-]Towards One Health Knowledge Networks: A Southern African Centre of Infectious Disease Surveillance case study Texto completo
2012
Eric Beda
The dynamic nature of new information and/or knowledge is a big challenge for information systems. Early knowledge management systems focused entirely on technologies for storing, searching and retrieving data; these systems have proved a failure. Juirsica and Mylopoulos1 suggested that in order to build effective technologies for knowledge management, we need to further our understanding of how individuals, groups and organisations use knowledge. As the focus on knowledge management for organisations and consortia alike is moving towards a keen appreciation of how deeply knowledge is embedded in people’s experiences, there is a general realisation that knowledge cannot be stored or captured digitally. This puts more emphasis in creating enabling environments for interactions that stimulate knowledge sharing. Our work aims at developing an un-obtrusive intelligent system that glues together effective contemporary and traditional technologies to aid these interactions and manage the information captured. In addition this system will include tools to aid propagating a repository of scientific information relevant to surveillance of infectious diseases to complement knowledge shared and/or acts as a point of reference. This work is ongoing and based on experiences in developing a knowledge network management system for the Southern African Centre of Infectious Disease Surveillance (SACIDS), A One Health consortium of southern African academic and research institutions involved with infectious diseases of humans and animals in partnership with world-renowned centres of research in industrialised countries.
Mostrar más [+] Menos [-]Investigation of water sources as reservoirs of <i>Vibrio cholerae</i> in Bepanda, Douala and determination of physico-chemical factors maintaining its endemicity Texto completo
2012
Akoachere J.-F.K. Tatah | Kwedjeu M.C. Pulcherie | Ndip L. Mande | Njom H. Akum
Cholera remains a significant cause of mortality in developing countries. Outbreaks of the disease are associated with poverty, lack of potable water and poor sanitation. The survival and persistence of Vibrio cholerae in water has been shown to depend on physico-chemical factors. We studied water sources in Bepanda, an overcrowded neighbourhood in Douala, Cameroon, with limited access to portable water and very poor sanitary conditions as reservoirs of V. cholerae. We analysed 318 samples from various sources (well, tap, stream) from February to July 2009 using standard microbiological techniques and characterised isolates serologically using the polyvalent O1/O139 antisera. Susceptibility to antibiotics previously used for cholera treatment in Douala was studied using the disk diffusion method. Physico-chemical factors (temperature, pH and salinity) that could maintain the endemicity of the organism were analysed using standard methods. Eighty-seven (27.4%) samples were contaminated, with high isolation rates being obtained from streams (52.4%) and wells (29.8%). The number of isolates was significantly higher (P < 0.05) in the rainy season (35.5%). We detected 23 (24%) O1 serogroup isolates in streams and wells, whilst 64 (66.6%) were non-O1/non-O139. Temperature and salinity correlated positively with the occurrence of the organisms. All isolates were susceptible to fluoroquinolones but high resistance rates to trimethoprim or sulfamethozaxole and tetracycline were observed. Vibrio cholerae is endemic in Bepanda with O1 and non-O1/non-O139 serogroups co-existing in the streams and wells hence the possibility of future outbreaks of cholera if sanitation and drinking water quality are not improved. Temperature and salinity are amongst the factors maintaining the endemicity of the organism.
Mostrar más [+] Menos [-]Infectious diseases of economic importance: Molecular biological characteristics of foot-and-mouth disease viruses collected in Tanzania from 1967 to 2009 Texto completo
2012
Christopher J. Kasanga | R. Sallu | C.A.R. Mpelumbe-Ngeleja | J. Wadsworth | N.P. Ferris | G.H. Hutchings | P.P. Wambura | M.G.S. Yongolo | N.J. Knowles | Donald P. King | M.M. Rweyemamu
Foot-and-mouth disease (FMD) is endemic in Tanzania. Since the first reports in 1954, FMD has caused significant economic losses in the country due to mortality and morbidity of livestock and costs associated with controlling the disease. The aim of this study was to review the serotype and genetic relationships of the FMD virus (FMDV) recovered from outbreaks in Tanzania, and compare them with viruses detected from elsewhere in the sub-Saharan region. At the World Reference Laboratory for foot-and-mouth disease (WRLFMD), a total of 106 FMD viruses have been isolated from samples collected between 1967 and 2009 from northern, southern, eastern and central parts of Tanzania. The presence of FMDV was determined by laboratory methods such as VI, CF, antigen ELISA and RT-PCR. Phylogenies of VP1 sequences were determined by the Neighbour-joining method. Foot-and-mouth disease virus SAT1 was the most frequent serotype (46.2%; n = 49) isolated in Tanzania followed by O (26.4%; n = 27), A (14.1%; n = 15) and SAT 2 (11.3%; n = 13). Genotyping showed that type O viruses fell into either the EAST AFRICA 1 (EA-1) or EA-2 topotypes, type A’s into the AFRICA topotype (genotype I), type SAT 1’s into topotype I and type SAT 2’s into topotype IV. This study reveals that serotypes A, O, SAT1 and SAT2 cause FMD outbreaks in Tanzania. Recent samples from outbreaks in 2008, 2009 and 2010 have been typed as serotypes A, O, SAT1 and SAT2. Phylogenetic analysis of FMDV isolates from Tanzania showed that they are genetically related to lineages and topotypes from West and East Africa. In Tanzania, lack of comprehensive animal movement records and inconsistent vaccination programs make it difficult to determine the exact source of FMD outbreaks or to trace the transmission of the disease over time. Therefore, further collection and analysis of samples from domestic and wild animals, together with improved local epidemiological investigation of FMD outbreaks is required to elucidate the complex epidemiology of FMD in the sub-Saharan region.
Mostrar más [+] Menos [-]Comparison of transcoelomic, contrast transcoelomic, and transesophageal echocardiography in anesthetized red-tailed hawks (Buteo jamaicensis) Texto completo
2012
Beaufrere, Hugues | Pariaut, Romain | Rodríguez, Daniel | Nevarez, Javier G. | Tully, Thomas N.
Objective: To assess the agreement and reliability of cardiac measurements obtained with 3 echocardiographic techniques in anesthetized red-tailed hawks (Buteo jamaicensis). Animals: 10 red-tailed hawks. Procedures: Transcoelomic, contrast transcoelomic, and transesophageal echocardiographic evaluations of the hawks were performed, and cineloops of imaging planes were recorded. Three observers performed echocardiographic measurements of cardiac variables 3 times on 3 days. The order in which hawks were assessed and echocardiographic techniques were used was randomized. Results were analyzed with linear mixed modeling, agreement was assessed with intraclass correlation coefficients, and variation was estimated with coefficients of variation. Results: Significant differences were evident among the 3 echocardiographic methods for most measurements, and the agreement among findings was generally low. Interobserver agreement was generally low to medium. Intraobserver agreement was generally medium to high. Overall, better agreement was achieved for the left ventricular measurements and for the transesophageal approach than for other measurements and techniques. Conclusions and Clinical Relevance: Echocardiographic measurements in hawks were not reliable, except when the left ventricle was measured by the same observer. Furthermore, cardiac morphometric measurements may not be clinically important. When measurements are required, one needs to consider that follow-up measurements should be performed by the same echocardiographer and should show at least a 20% difference from initial measurements to be confident that any difference is genuine.
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