NR AWCJ
AU Bona,M.C.; Pitti,M.; Possidente,R.; Maurella,C.; Caramelli,M.; Ru,G.
TI Incidence data to describe the Italian scrapie epidemic
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions EPI-02
PT Konferenz-Poster
AB While prevalence data of the Scrapie epidemic in Italy are promptly available since the implementation of active surveillance in 2002, incidence data have never been used to depict the descriptive epidemiology of the disease. The aim of this work is to quantify the incidence of Scrapie in outbreaks reported during the period 1995-2005. In order to collect information, farmers of 215 flocks were interviewed (97% outbreaks) using a standardised questionnaire, containing the following subjects: number of sheep and goats (stratified into three age classes: < 2 year old, 2 to 4 year old, >4 year old), number of suspected ill animals (with Scrapie-like symptoms) observed during the 12 months before the confirmation. Incidence was calculated both in the total population of Scrapie-affected flocks and within each flock. By each species and age, within flock specific incidence was also calculated. Within flock incidence density, during the 12 months preceding the confirmation of the positivity of the flock, was 2,1 cases per 100 animal/years in sheep (CI 95% 2,0-2,2) and 8,8 cases per 100 animal/years in goats (CI 95% 8,1-9,6).Remarkable differences in the age adjusted incidence were evident by time, place and characteristics of the affected animals. Incidence differences between the two species and in the geographical areas, could be due to the presence of specific risk factors, e.g. the use of a vaccine against M. agalactiae in the Central and Southern Italian regions in the mid 90's. The different type of surveillance (active vs passive) may explain the difference incidence as well. The study of age-specific incidence within flock indicates as expected, that the 2 to 4 years old small ruminants showed the highest incidence of Scrapie.
AD Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle D'Aosta, CEA, Turin, Italy. E-mail: cristina.bona@izsto.it
SP englisch
PO Italien