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Animal Reservoirs (animal + reservoir)
Selected AbstractsImmune response to leishmania: paradox rather than paradigmFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2007Parul Tripathi Abstract The leishmaniases are a group of diseases caused by protozoan parasites of the genus Leishmania. Various Leishmania species can cause human infection, producing a spectrum of clinical manifestations. It is estimated that 350 million people are at risk, with a global yearly incidence of 1,1.5 million for cutaneous and 500 000 for visceral leishmaniasis (VL). VL is a major cause of morbidity and mortality in East Africa and the Indian subcontinent. Coinfection with HIV enhances the risk of the disease. The only control measure currently available in India is case detection and treatment with antimonial drugs, which are expensive, not always available and cannot be self-administered. Newer drugs like oral miltefosine have not become widely available. Vector and reservoir control is difficult due to the elusive nature of the vector and the diversity of the animal reservoir. A detailed knowledge of immune response to the parasite would help in designing prophylactic and therapeutic strategies against this infection. [source] Water quality and Cryptosporidium distribution in an upland water supply catchment, Cumbria, UKHYDROLOGICAL PROCESSES, Issue 7 2007A. Sturdee Abstract Four micro-catchment (MC) areas were identified to represent the main terrain types of a remote, sparsely populated upland valley catchment of 18 km2 in Cumbria, UK. These were improved land with good grazing (IB), steeply sloping land with rough grazing (SG), wet moorland with sparse grazing (WM) and enclosed woodland that excluded livestock and deer (EW). Each MC contained the origin of a small stream that flowed into Swindale Beck, the river draining the valley. The water quality during the 14-month study, as judged by chemical and physical parameters, was excellent, but it could not be regarded as pristine because of the frequent presence of Cryptosporidium oocysts arising from livestock and wild mammal faeces. Oocysts (0·2,5·6 l,1) detected by genus-specific immunofluorescent antibody were found in 32% of 188 water samples tested: ranking order EW 44%, IB 34%, Beck 30%, SG and WM 26%. Similarly, oocysts were identified in 9·5% of 1730 faecal samples. Small wild mammals (28%), calves (15·7%) and lambs (8·1%) were the dominant sources, whereas adult livestock (1·8%) and large wild mammals (4·8%) were less important. Autumn showed the highest occurrence of oocysts for both water and faecal samples. No hydrological controls were found to have a significant impact on the occurrence or concentration of oocysts in the main river or in the MCs, suggesting that their presence is controlled by seasonal changes in pathogen prevalence in the animal reservoir. Copyright © 2006 John Wiley & Sons, Ltd. [source] Diversity of Escherichia coli O157 in a longitudinal farm study using multiple-locus variable-number tandem-repeat analysisJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2008A.M. Urdahl Abstract Aims:, To perform a longitudinal study of the diversity of Escherichia coli O157 from a ruminant pasture/stream environment using multiple-locus variable-number tandem-repeat analysis (MLVA). Methods and Results:, Samples of faecal droppings from grazing ruminants and from an adjacent stream were tested longitudinally for E. coli O157 by enrichment and immunomagnetic separation (IMS). Using MLVA, 24 different profiles were identified from a total of 231 E. coli O157 isolates, of which 80 were included in a similarity analysis. Four main clusters with several subclusters were observed. Although there was close contact between sheep and cattle during the study period, E. coli O157 was surprisingly not detected from cattle faeces. Conclusions:, The cluster analysis indicated both unrelated and closely related E. coli O157 strains. The choice of loci to target in MLVA is important for the subtyping result, as loci with high diversities are essential for discriminating between closely related isolates. Significance and Impact of the Study:, There is a lack of data available on the use of MLVA to describe E. coli O157 diversity and changes over time in the animal reservoirs and the environment. Such data are needed in order to further develop MLVA as a typing method. [source] Overview on SARS in Asia and the WorldRESPIROLOGY, Issue 2003WK LAM Severe Acute Respiratory Syndrome (SARS) is the first major novel infectious disease to hit the international community in the 21st century. It originated in southern China in November 2002, reached Hong Kong in February 2003 and spread rapidly thereafter to 29 countries/regions on five continents. At the end of the epidemic, the global cumulative total was 8098 with 774 deaths. Seven Asian countries/regions were among the top ten on the list. Mainland China and Hong Kong, SAR, accounted for 87% of all cases and 84% of all deaths. Severe acute respiratory syndrome is caused by a novel coronavirus. It has alarmed the world with its infectivity and significant morbidity and mortality, its lack of a rapid, reliable diagnostic test and lack of effective specific treatment and vaccination. The adverse impact on travel and business around the world, particularly in Asia, has been enormous. Some lessons learnt from this epidemic included: (1) any outbreak of infectious disease can rapidly spread around the world by air travel; (2) early reporting of the outbreak to neighbouring countries/regions and the World Health Organization is essential to prevent international spread; and (3) infection control, tracing and quarantine of contacts are essential to control the epidemic. Many questions remain unanswered, including the origin and pathogenesis of the novel coronavirus, the natural history and the best specific treatment of the disease. The SARS-CoV has probably jumped from an animal host to humans. There is an urgent need to evaluate the human,animal habitat in southern China and to remove animal reservoirs if found. [source] Cross-species transfer of viruses: implications for the use of viral vectors in biomedical research, gene therapy and as live-virus vaccinesTHE JOURNAL OF GENE MEDICINE, Issue 10 2005Derrick Louz Abstract Summary All living organisms are continuously exposed to a plethora of viruses. In general, viruses tend to be restricted to the natural host species which they infect. From time to time viruses cross the host-range barrier expanding their host range. However, in very rare cases cross-species transfer is followed by the establishment and persistence of a virus in the new host species, which may result in disease. Recent examples of viruses that have crossed the species barrier from animal reservoirs to humans are hantavirus, haemorrhagic fever viruses, arboviruses, Nipah and Hendra viruses, avian influenza virus (AI), monkeypox virus, and the SARS-associated coronavirus (SARS-CoV). The opportunities for cross-species transfer of mammalian viruses have increased in recent years due to increased contact between humans and animal reservoirs. However, it is difficult to predict when such events will take place since the viral adaptation that is needed to accomplish this is multifactorial and stochastic. Against this background the intensified use of viruses and their genetically modified variants as viral gene transfer vectors for biomedical research, experimental gene therapy and for live-vector vaccines is a cause for concern. This review addresses a number of potential risk factors and their implications for activities with viral vectors from the perspective of cross-species transfer of viruses in nature, with emphasis on the occurrence of host-range mutants resulting from either cell culture or tropism engineering. The issues are raised with the intention to assist in risk assessments for activities with vector viruses. Copyright © 2005 John Wiley & Sons, Ltd. 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