Since the isolation of Helicobacter pylori, many new Helicobacter species have been identified from the gastrointestinal tract in humans and animals. Morphological, epidemiological and genotypic data suggest the involvement of animal helicobacters in these infections. In this paper, a review of the literature addressing the current knowledge about epidemiology, diagnosis, pathogenesis and therapy of these infections is given. After an incubation period lasting a few weeks to several months, BDV-infection causes locomotor and sensory dysfunctions followed by paralysis and death.
Natural infections seem to be subclinical in most cases.
Harcourt Publishers Ltd. Micro-evolution and emergence of pathogens. Rott R. De Groote D. Ducatelle R. Haesebrouck F. Changes in the epidemiology of infectious diseases are the direct result of ecological and evolutionary changes in hosts and parasites. Precisely what the causal processes are is rarely known in any particular case, and this hinders the design of appropriate control strategies. This is particularly so for emerging infections, as opportunity is rapidly lost to study the ecological parameters which might have affected initial emergence. However, molecular evolutionary studies of the pathogens can yield data which discriminate between possible causes.