Prevalence of gastrointestinal bacterial pathogens in a population of zoo animals.

Faecal prevalence of gastrointestinal bacterial pathogens, including Campylobacter, Escherichia coli O157:H7, Salmonella, Shigella, Yersinia, as well as Arcobacter, were examined in 317 faecal specimens from 44 animal species in Belfast Zoological Gardens, during July-September 2006. Thermophilic campylobacters including Campylobacter jejuni, Campylobacter coli and Campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (11 of 44; 25%). Yersinia spp. were isolated from seven animal species (seven of 44; 15.9%) and included, Yersinia enterocolitica (five of seven isolates; 71.4%) and one isolate each of Yersinia frederiksenii and Yersinia kristensenii. Only one isolate of Salmonella was obtained throughout the entire study, which was an isolate of Salmonella dublin (O 1,9,12: H g, p), originating from tiger faeces after enrichment. None of the animal species found in public contact areas of the zoo were positive for any gastrointestinal bacterial pathogens. Also, water from the lake in the centre of the grounds, was examined for the same bacterial pathogens and was found to contain C. jejuni. This study is the first report on the isolation of a number of important bacterial pathogens from a variety of novel host species, C. jejuni from the red kangaroo (Macropus rufus), C. lari from a maned wolf (Chrysocyon brachyurus), Y. kristensenii from a vicugna (Vicugna vicugna) and Y. enterocolitica from a maned wolf and red panda (Ailurus fulgens). In conclusion, this study demonstrated that the faeces of animals in public contact areas of the zoo were not positive for the bacterial gastrointestinal pathogens examined. This is reassuring for the public health of visitors, particularly children, who enjoy this educational and recreational resource.

The cascade model: an alternative to comorbidity in the pathogenesis of posttraumatic stress disorder.

Comorbidity has been used extensively to explain the numerous co-occurring psychiatric syndromes accompanying chronic posttraumatic stress disorder (PTSD). A cascade model is proposed as an alternative to comorbidity for the pathogenesis and clinical course of the condition. This model allows for a dynamic, integrated conceptualization of disease progression in PTSD. Findings in the clinical, epidemiological, neurobiological, and psychosocial literature which might support this model are described. Conceptual and heuristic difficulties and/or potential objections to the model are also examined. Finally, diagnostic and treatment implications as well as potential research applications of the model are discussed.

Should there be a clinical typology of posttraumatic stress disorder?

OBJECTIVE: The current classification of posttraumatic stress disorder in acute, chronic and delayed-onset types is incomplete and of limited usefulness. The present paper explores the possibilities of a clinically-based typology that would reflect both the patients' syndromic presentation and modern research findings. METHOD: Review of current clinical and research literature, with a critical examination of proposed typologies, parameters utilised, applicability and relevance; elaboration of theoretical and practical bases of a clinical typology of posttraumatic stress disorder. RESULTS: None of the existing posttraumatic stress disorder typologies presents a clinically comprehensive scope. A typology supported by literature findings and clinical observations is proposed. The six clinical types are depressive, dissociative, somatomorphic, psychotomorphic, organomorphic and 'neurotic-like'. Substance abuse and personality disorder-like variants remain as areas of investigation. CONCLUSIONS: The proposed typology, while accepting the nuclear manifestations of posttraumatic stress disorder, highlights prominent coexisting symptoms that define the clinical appearance of different patients. The typological approach in posttraumatic stress disorder does not carry the ambiguities of comorbidity, and facilitates a more specific and appropriate management of the cases.

Unique patterns of comorbidity in posttraumatic stress disorder from different sources of trauma.

While there are many studies of comorbidity in combat veterans with posttraumatic stress disorder (PTSD), studies of PTSD from other sources of trauma (e.g., disasters, crimes, and civil violence) are just beginning to emerge. This is the first formal review comparing patterns of comorbidity in PTSD from different sources of trauma. Specific attention is given to the relative frequencies of substance abuse, depression, generalized anxiety, phobic, panic, somatization, psychotic, and personality disorders. The findings reveal that although similarities exist, the comorbidity profiles differ according to the type of trauma experienced and the population studied. Additionally, the evidence suggests that the associated psychiatric disorders are not truly comorbid, but are interwoven with the PTSD.