The time-course of a scrapie outbreak

被引：5

作者：

McIntyre K.M. ^{[1
]}

Gubbins S. ^{[1
]}

Goldmann W. ^{[2
]}

Stevenson E. ^{[1
]}

Baylis M. ^{[1
,3
]}

机构：

[1] Institute for Animal Health, Pirbright Laboratory, Pirbright, Surrey, Ash Road

[2] Institute for Animal Health, Neuropathogenesis Unit, Ogston Building, Edinburgh, West Mains Road

[3] University of Liverpool Veterinary Teaching Hospitals, Leahurst, Neston, South Wirral, Chester High Road

来源：

BMC Veterinary Research | / 2卷 / 1期

关键词：

Adjust Odds Ratio; Scrapie; Binary Logistic Regression Model; Susceptible Animal; Longe Incubation Period;

D O I：

10.1186/1746-6148-2-20

中图分类号：

学科分类号：

摘要：

Background: Because the incubation period of scrapie has a strong host genetic component and a dose-response relationship, it is possible that changes will occur during an outbreak, especially in the genotypes of cases, age-at-onset of disease and, perhaps, the clinical signs displayed. We investigated these factors for a large outbreak of natural scrapie, which yielded sufficient data to detect temporal trends. Results: Cases occurred mostly in two genotypes, VRQ/VRQ and VRQ/ARQ, with those early in the outbreak more likely to be of the VRQ/VRQ genotype. As the epidemic progressed, the age-at-onset of disease increased, which reflected changes in the genotypes of cases rather than changes in the age-at-onset within genotypes. Clinical signs of cases changed over the course of the outbreak. As the epidemic progressed VRQ/VRQ and VRQ/ARQ sheep were more likely to be reported with behavioural changes, while VRQ/VRQ sheep only were less likely to be reported with loss of condition. Conclusion: This study of one of the largest scrapie outbreaks in the UK allowed investigation of the effect of PrP genotype on other epidemiological parameters. Our analysis indicated that, although age-at-onset and clinical signs changed over time, the observed changes were largely, but not exclusively, driven by the time course of the PrP genotypes of cases. © 2006 McIntyre et al; licensee BioMed Central Ltd.

引用

共 18 条

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