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Surveillance and molecular epidemiology of avian influenza viruses from birds in zoos, backyard flocks and live bird markets in Korea
2012
Jang, J.W., Seoul National University, Seoul, Republic of Korea | Kim, I.H., Seoul National University, Seoul, Republic of Korea | Kwon, H.J., Seoul National University, Seoul, Republic of Korea | Hong, S.M., Seoul National University, Seoul, Republic of Korea | Kim, J.H., Seoul National University, Seoul, Republic of Korea
The circulation and infection of avian influenza virus (AIV) in zoos and backyard flocks has not been systematically investigated. In the present study, we surveyed the birds including those in live bird markets (LBMs) and evaluated co-circulation of AIVs among them. Overall, 26 H9N2 AIVs and one H6N2 AIV were isolated from backyard flocks and LBMs, but no AIVs were isolated from zoo birds. Genetic analysis of the HA and NA genes indicated that most of the H9N2 AIVs showed higher similarities to AIVs circulating in domestic poultry than to those in wild birds, while the H6N2 AIV isolate from an LBM did to AIVs circulating in migratory wild birds. In serological tests, 15% (391/2619) of the collected sera tested positive for AIVs by competitive-ELISA. Among them, 34% (131/391) of the sera tested positive for AIV H9 antigen by HI test, but only one zoo sample was H9 positive. Although AIVs were not isolated from zoo birds, the serological results indicated that infection of AIVs might occur in zoos. It was also confirmed that H9N2 AIVs continue to circulate and evolve between backyard flocks and LBMs. Therefore, continuous surveillance and monitoring of these flocks should be conducted to control further epidemics.
Mostrar más [+] Menos [-]Prevalence and antimicrobial susceptibility of Brachyspira species in pigs in Korea
2012
Lim, S.K., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Lee, H.S., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Nam, H.M., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Cho, Y.S., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Jung, S.C., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Joo, Y.S., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea
The purpose of this study was to investigate the prevalence of Brachyspira species and antimicrobial susceptibility of Brachyspira (B.) hyodysenteriae isolates in Korea. A total of fifty-five Brachyspira species were isolated; five (1.0%) beta-hemolytic Brachyspira species and 50 (10.4%) weak hemolytic Brachyspira species from 116 different diarrheic pig samples and 367 apparently normal pig samples. In farm level, beta hemolytic and weak hemolytic Brachyspira species were detected in 7.4% (5/68) and 19.1% (13/68) of tested pig farms, respectively. By phenotypic and genotypic characterization, all beta hemolytic Brachyspira isolates was classified as group Ⅰ (B. hyodysenteriae), whereas weak hemolytic Brachyspira species isolates were group Ⅲ (B. innocens or B. murdochii). B. hyodysenteriae isolates showed high level of minimum inhibition concentrations to macrolide antimicrobials. This study shows that the prevalence of pathogenic B. hyodysenteriae in pigs is low but antimicrobial resistance of the pathogens is high in Korea. This is the first report of the prevalence of Brachyspira group Ⅲ and antimicrobial susceptibility of B. hyodysenteriae in pigs in Korea. Our results could provide basic data for the management and treatment guidelines of Brachyspira infection.
Mostrar más [+] Menos [-]Expression of ErbB receptors in the pre-pubertal and pubertal virgin mammary glands of dairy cows
2012
Lee, B.W., Kangwon National University, Chuncheon, Republic of Korea | Kim, Y.H., Kangwon National University, Chuncheon, Republic of Korea | Jeon, B.S., Kangwon National University, Chuncheon, Republic of Korea | Naresh Kumar Singh, Kangwon National University, Chuncheon, Republic of Korea | Kim, W.H., Jeonnam Livestock Research Institute, Gangjin, Republic of Korea | Kim, M.J., National Institute of Animal Science, RDA, Cheonan, Republic of Korea | Yoon, B.I., Kangwon National University, Chuncheon, Republic of Korea
In the present study, we investigated the expression patterns of ErbB family proteins in the pre-pubertal and pubertal mammary glands of dairy cows in association with gland development. For this study, we performed immunohistochemistry for ErbB-1-4 and Ki-67 cell proliferation marker. We found that the pre-pubertal and pubertal mammary glands had typical structures, including ducts and terminal end buds embedded in the stroma, and no development of lobuloalveolar structures. On immunohistochemistry, ErbB-2 and ErbB-3 were strongly expressed in the cytoplasm and nuclei in the epithelial cells of mammary ducts and terminal end buds, and stromal cells, whereas ErbB-1 and ErbB-4 were weakly expressed only in the cytoplasm of gland epithelium and stromal cells, irrespective of the developmental stage. Cell proliferation was inactive in the mammary gland cell compartments in both phases. Thus, expression of the ErbB family in the developing mammary glands was not associated with their functional effects, such as cell proliferation and lobuloalveolar development. In conclusion, ErbB receptors were differentially expressed in the epithelial and stromal cells of virgin mammary glands of dairy cows. Compared with rodent mammary glands, ErbB-3 and ErbB-4 were found to be highly expressed in bovine mammary glands.
Mostrar más [+] Menos [-]Towards one Africa, one health: The Southern African Centre for Infectious Disease Surveillance One Health focus on infectious diseases
2012
Rweyemamu, Mark M.(Sokoine University of Agriculture Southern African Centre for infectious diseases surveillance) | Paweska, Janusz(Sokoine University of Agriculture Southern African Centre for infectious diseases surveillance) | Kambarage, Dominic(Sokoine University of Agriculture Southern African Centre for infectious diseases surveillance) | Namuba, Filomena(Sokoine University of Agriculture Southern African Centre for infectious diseases surveillance)
Ebola virus outbreaks in Africa: Past and present
2012
Muyembe-Tamfum, J.J.(Institut national de Recherche Biomédicale) | Mulangu, S.(Southern African Centre for Infectious Disease Surveillance) | Masumu, Justin(Institut national de Recherche Biomédicale) | Kayembe, J.M.(Université de Kinshasa) | Kemp, A.(National Institute for Communicable Diseases of the National Health Laboratory Service) | Paweska, Janusz T(National Institute for Communicable Diseases of the National Health Laboratory Service)
Ebola haemorrhagic fever (EHF) is a zoonosis affecting both human and non-human primates (NHP). Outbreaks in Africa occur mainly in the Congo and Nile basins. The first outbreaks of EHF occurred nearly simultaneously in 1976 in the Democratic Republic of the Congo (DRC, former Zaire) and Sudan with very high case fatality rates of 88% and 53%, respectively. The two outbreaks were caused by two distinct species of Ebola virus named Zaire ebolavirus (ZEBOV) and Sudan ebolavirus (SEBOV). The source of transmission remains unknown. After a long period of silence (1980-1993), EHF outbreaks in Africa caused by the two species erupted with increased frequency and new species were discovered, namely Cote d'lvoire ebolavirus (CIEBOV) in 1994 in the Ivory Coast and Bundibugyo ebolavirus (BEBOV) in 2007 in Uganda. The re-emergence of EHF outbreaks in Gabon and Republic of the Congo were concomitant with an increase in mortality amongst gorillas and chimpanzees infected with ZEBOV. The human outbreaks were related to multiple, unrelated index cases who had contact with dead gorillas or chimpanzees. However, in areas where NHP were rare or absent, as in Kikwit (DRC) in 1995, Mweka (DRC) in 2007, Gulu (Uganda) in 2000 and Yambio (Sudan) in 2004, the hunting and eating of fruit bats may have resulted in the primary transmission of Ebola virus to humans. Human-to-human transmission is associated with direct contact with body fluids or tissues from an infected subject or contaminated objects. Despite several, often heroic field studies, the epidemiology and ecology of Ebola virus, including identification of its natural reservoir hosts, remains a formidable challenge for public health and scientific communities.
Mostrar más [+] Menos [-]The African buffalo: A villain for inter-species spread of infectious diseases in southern Africa
2012
Michel, Anita L.(University of Pretoria Department of Veterinary Tropical Diseases) | Bengis, Roy G(Directorate Veterinary Services)
The African buffalo (Syncerus caffer) is a large wild bovid which until recently ranged across all but the driest parts of sub-Saharan Africa, and their local range being limited to about 20 km from surface water. They are of high ecological value due to their important role as bulk feeders in the grazing hierarchy. They also have high economic value, because they are one of the sought after 'Big Five' in the eco-tourism industry. In Africa, buffaloes have been recognised for some time as an important role player in the maintenance and transmission of a variety of economically important livestock diseases at the wildlife and/or livestock interface. These include African strains of foot-and-mouth disease (FMD), Corridor disease (theileriosis), bovine tuberculosis and bovine brucellosis. For a number of other diseases of veterinary importance, African buffaloes may also serve as amplifier or incidental host, whereby infection with the causative pathogens may cause severe clinical signs such as death or abortion as in the case of anthrax and Rift Valley fever, or remain mild or subclinical for example heartwater. The long term health implications of most of those infections on the buffalo at a population level is usually limited, and they do not pose a threat on the population's survival. Because of their ability to harbour and transmit important diseases to livestock, their sustainable future in ecotourism, trade and transfrontier conservation projects become complex and costly and reliable diagnostic tools are required to monitor these infections in buffalo populations.
Mostrar más [+] Menos [-]Electronic Integrated Disease Surveillance System and Pathogen Asset Control System
2012
Wahl, Tom G.(MosAlarko Plaza One) | Burdakov, Aleksey V.(MosAlarko Plaza One) | Oukharov, Andrey O.(MosAlarko Plaza One) | Zhilokov, Azamat K.(MosAlarko Plaza One)
Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS. Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA).
Mostrar más [+] Menos [-]New technologies to diagnose and monitor infectious diseases of livestock: Challenges for sub-Saharan Africa
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 [-]One Health - 'joining the dots'
2012
Dockrell, Hazel M(London School of Hygiene & Tropical Medicine Department of Immunology and Infection)
A socio-economic approach to One Health policy research in southern Africa
2012
Kayunze, Kim A.(Sokoine University of Agriculture Development Studies Institute) | Kiwara, Angwara D.(Muhimbili University of Health and Allied Sciences Institute of Development Studies) | Lyamuya, Eligius(Muhimbili University of Health and Allied Sciences) | Kambarage, Dominic M.(Sokoine University of Agriculture) | Rushton, Jonathan(Royal Veterinary College) | Coker, Richard(Mahidol University) | Kock, Richard(Royal Veterinary College) | Rweyemamu, Mark M.(Sokoine University of Agriculture)
One-health approaches have started being applied to health systems in some countries in controlling infectious diseases in order to reduce the burden of disease in humans, livestock and wild animals collaboratively. However, one wonders whether the problem of lingering and emerging zoonoses is more affected by health policies, low application of one-health approaches, or other factors. As part of efforts to answer this question, the Southern African Centre for Infectious Disease Surveillance (SACIDS) smart partnership of human health, animal health and socio-economic experts published, in April 2011, a conceptual framework to support One Health research for policy on emerging zoonoses. The main objective of this paper was to identify which factors really affect the burden of disease and how the burden could affect socio-economic well-being. Amongst other issues, the review of literature shows that the occurrence of infectious diseases in humans and animals is driven by many factors, the most important ones being the causative agents (viruses, bacteria, parasites, etc.) and the mediator conditions (social, cultural, economic or climatic) which facilitate the infection to occur and hold. Literature also shows that in many countries there is little collaboration between medical and veterinary services despite the shared underlying science and the increasing infectious disease threat. In view of these findings, a research to inform health policy must walk on two legs: a natural sciences leg and a social sciences one.
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