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Potential Vector (potential + vector)
Selected AbstractsPotential vectors and hosts of rickettsia spp: epidemiological studies in the Vale do Paraíba, state of Rio de Janeiro/BrazilCLINICAL MICROBIOLOGY AND INFECTION, Issue 2009G. S. Gazeta No abstract is available for this article. [source] Are there Characteristics of Infectious Diseases that Raise Special Ethical Issues?1DEVELOPING WORLD BIOETHICS, Issue 1 2004Charles B. Smith ABSTRACT This paper examines the characteristics of infectious diseases that raise special medical and social ethical issues, and explores ways of integrating both current bioethical and classical public health ethics concerns. Many of the ethical issues raised by infectious diseases are related to these diseases' powerful ability to engender fear in individuals and panic in populations. We address the association of some infectious diseases with high morbidity and mortality rates, the sense that infectious diseases are caused by invasion or attack on humans by foreign micro-organisms, the acute onset and rapid course of many infectious diseases, and, in particular, the communicability of infectious diseases. The individual fear and community panic associated with infectious diseases often leads to rapid, emotionally driven decision making about public health policies needed to protect the community that may be in conflict with current bioethical principles regarding the care of individual patients. The discussion includes recent examples where dialogue between public health practitioners and medical-ethicists has helped resolve ethical issues that require us to consider the infected patient as both a victim with individual needs and rights and as a potential vector of disease that is of concern to the community. [source] The zoophilic fruitfly Phortica variegata: morphology, ecology and biological nicheMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2006D. OTRANTO Abstract Flies belonging to the subfamily Steganinae (Drosophilidae) display unusual zoophilic feeding habits at the adult and/or larval stage. Phortica variegata (Fallén) feeds on tears or eye liquid around the eyes of humans and carnivores. When feeding it is a potential vector of Thelazia callipaeda (Railliet and Henry) eyeworms. Adult and larval stages of this fly may be easily confused with other species belonging to the same genus, and little is known on the biology and ecology of P. variegata. In April,November 2005, a total of 969 P. variegata were collected in an area with a high prevalence of canine thelaziosis. The number of flies collected weekly was then related to climatic and environmental parameters (e.g. temperature, relative humidity and total rainfall) recorded daily at the collection site. The highest number of Phortica were collected during July,August. The sex ratio (number of males : females) rose from , 0.5 during May,July, to , 3.0 in August and 181 during September,October. Distributional data, representing 242 sites at which P. variegata has been collected in Europe, were analysed using a desktop implementation of the genetic algorithm for rule-set prediction (GARP) to model ecological requirements across Europe, as well as in Italy. P. variegata is shown to be mainly active at 20,25 °C and 50,75% RH. The ecological niche model suggests with a high degree of confidence that large areas of Europe are likely to represent suitable habitat for this species, mostly concentrated in central Europe. The results reported here contribute basic knowledge on the ecology and geographical distribution of P. variegata flies, which will be fundamental to gaining a better understanding of their role as vectors of human and animal pathogens. [source] Phlebotomus (Adlerius) halepensis vector competence for Leishmania major and Le. tropicaMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2003J. Sádlová Abstract., In Eurasia, phlebotomine sandflies of the subgenus Adlerius (Diptera: Psychodidae) comprise about 20 known species. Some are suspected vectors of visceral leishmaniasis (VL) and at least one species has been implicated as a vector of cutaneous leishmaniasis (CL). We tested Phlebotomus (Adlerius) halepensis Theodor (Jordan strain) for CL vector competence, compared with three standard vectors: Phlebotomus (Phlebotomus) duboscqi N-L. from Senegal, Phlebotomus (Paraphlebotomus) sergenti Parrot from Turkey and the Neotropical Lutzomyia longipalpis (L. & N) (Jacobina strain). Sandfly females were membrane-fed on amastigote suspensions of Leishmania major Y. & S. and Le. tropica (Wright) (Kinetoplastida: Trypanosomatidae) and examined for parasite development 3, 6 and 10 days post-infection. Phlebotomus halepensis showed high susceptibility to both leishmanias, supporting typical suprapylarian parasite development similar to the other vectors. Phlebotomus halepensis infection rates were ,90% for Le. major and ,80% for Le. tropica, with high parasite densities. Development of infections was relatively fast, colonizing the thoracic midgut by 6 days post-bloodmeal in every case and reaching the stomodeal valve in >80% of flies. In late-stage infections, 10 days post-bloodmeal, nearly all P. halepensis females had cardia and stomodeal valve filled with very high numbers of parasites and some Le. tropica -infected females had promastigotes in the pharynx and proboscis. Host choice experiments in the laboratory showed that P. halepensis females fed readily on rat or rabbit and preferred the human forearm. In view of its vector competence and partial anthropophily, we infer that P. halepensis is a potential vector of cutaneous as well as visceral leishmaniases. [source] African horse sickness epidemiology: vector competence of South African Culicoides species for virus serotypes 3, 5 and 8MEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2000G. J. Venter Summary The oral susceptibilities of 17 Culicoides species to infection with African horse sickness virus (AHSV) serotypes 3, 5 and 8 were determined by feeding field-collected midges on AHSV infected horse blood. The mean titres of virus in the bloodmeals for the three serotypes of AHSV were between 5.7 and 6.5 log10TCID50/ml. Virus was detected, after 10 days incubation at 23.5°C, in the Culicoides imicola Kieffer (Diptera: Ceratopogonidae) that had fed on blood containing AHSV 5 (8.5%) and 8 (26.8%), and in the Culicoides bolitinos Meiswinkel that had fed on AHSV 3 (3.8%), 5 (20.6%) and 8 (1.7%). Although 44.4% of the C. imicola were shown to have ingested AHSV 3 immediately after feeding, no virus was detected in 96 C. imicola after incubation. The relatively high titres of virus recorded in individual midges of both species after 10 days incubation suggested a fully disseminated infection. Previously, C. imicola was considered to be the only field vector of AHSV in Africa. Identifying C. bolitinos as a potential vector for AHSV is an important finding, which if proven will have a significant impact on our understanding of the epidemiology of AHS. No AHSVs could be detected in the other 15 species of Culicoides assayed, which suggests that some of the southern African Culicoides species are refractory to AHSV infection. However, further work with larger numbers of each species will be necessary to confirm this observation. [source] Fresh produce as a potential vector for bacterial human pathogensMICROBIAL BIOTECHNOLOGY, Issue 6 2009Gad Frankel [source] The inadvertent introduction into Australia of Trypanosoma nabiasi, the trypanosome of the European rabbit (Oryctolagus cuniculus), and its potential for biocontrolMOLECULAR ECOLOGY, Issue 10 2005P. B. HAMILTON Abstract Wild rabbits (Oryctolagus cuniculus) in Australia are the descendents of 24 animals from England released in 1859. We surveyed rabbits and rabbit fleas (Spilopsyllus cuniculi) in Australia for the presence of trypanosomes using parasitological and PCR-based methods. Trypanosomes were detected in blood from the European rabbits by microscopy, and PCR using trypanosome-specific small subunit ribosomal RNA (SSU rRNA) gene primers and those in rabbit fleas by PCR. This is the first record of trypanosomes from rabbits in Australia. We identified these Australian rabbit trypanosomes as Trypanosoma nabiasi, the trypanosome of the European rabbit, by comparison of morphology and SSU rRNA gene sequences of Australian and European rabbit trypanosomes. Phylogenetic analysis places T. nabiasi in a clade with rodent trypanosomes in the subgenus Herpetosoma and their common link appears to be transmission by fleas. Despite the strict host specificity of trypanosomes in this clade, phylogenies presented here suggest that they have not strictly cospeciated with their vertebrate hosts. We suggest that T. nabiasi was inadvertently introduced into Australia in the 1960s in its flea vector Spilopsyllus cuniculi, which was deliberately introduced as a potential vector of the myxoma virus. In view of the environmental and economic damage caused by rabbits in Australia and other islands, the development of a virulent or genetically modified T. nabiasi should be considered to control rabbits. [source] Are therapeutic ultrasound units a potential vector for nosocomial infection?PHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 2 2006Siobhan Schabrun Abstract Background and Purpose.,Nosocomial infections present a widespread problem in today's healthcare environment, with a significant number of patients acquiring an infection annually. With the contemporary transition of immunocompromised and high-risk patients to community-based care, therapeutic ultrasound has the potential to be a vector of infection in the physiotherapy setting. The purpose of the present study was to determine the degree of contamination on therapeutic ultrasound transducer heads and ultrasound gel after routine clinical use, and to evaluate the efficacy of recommended infection control procedures.,Method.,The study consisted of two phases. Using a prospective cross-sectional design, microbiological cultures were obtained from 44 transducer heads and 43 gels. Subjects were drawn from a variety of physiotherapy practice settings. All samples containing more than five colony forming units per cm2 were considered contaminated. Following these measurements, a repeated-measures design was used to re-evaluate the 44 transducer heads for the amount and type of bacteria present after cleaning with a 70% alcohol wipe.,Results.,Twenty-seven per cent of transducer heads and 28% of gels were contaminated. Transducer heads showed fairly low levels of contamination across the sample, with the majority of organisms isolated found in normal skin and environmental flora. Gels were heavily contaminated with opportunistic and potentially pathogenic organisms, including Stenotrophomonas maltophilia, Staphylococcus aureus, Acinetobacter baumannii and Rhodotorula mucilaginosa. No multi-resistant organisms were identified. Cleaning with 70% alcohol significantly reduced the level of contamination on transducer heads (p < 0.01).,Conclusions.,Therapeutic ultrasound equipment is a potential vector for nosocomial infection in physiotherapy patients. The risk of infection from transducer heads can be effectively removed by cleaning with 70% alcohol between patients. Further research into possible strategies to reduce the risk of infection from ultrasound gels is needed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Synthetic Diether-linked Cationic Lipids for Gene DeliveryCHEMICAL BIOLOGY & DRUG DESIGN, Issue 3 2006Dongliang Liu Quaternary ammonium lipids 2a,p, with diether linkages between hydrocarbon chains and their ammonium headgroups, were synthesized as potential vectors for cationic liposome-mediated gene delivery. Varying the length of carbon chains and quaternary ammonium heads as well as different anionic complexes will enable the study of the structure,function relationships of these cationic lipids in terms of gene delivery properties. [source] | |||||||||||||