NR AXSA
AU Maluquer de Motes,C.; Torres,J.M.; Pumarola,M.; Girones,R.
TI Survival of Prion Proteins in Environmental Matrices
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Epidemiology, Risk Assessment and Transmission P04.104
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
Several publications have suggested the environment as a possible route of transmission, especially for sheep scrapie and cervid Chronic Wasting Disease (CWD). The role of the environment as a reservoir for these disorders is difficult to prove and faces a considerable lack of information. In this work, different methodologies have been developed to evaluate the survival and inactivation of TSE agents in environmental matrices.
Different slaughterhouse and urban sewage samples were spiked with diverse strains of either scrapie or BSE agents and kept under controlled conditions for extended periods of time. Aliquots of every experiment were sequentially collected and concentrated according to a methodology specifically selected for each type of matrix. Sensitivity of the methods developed was estimated among 2-10 µg of infected tissue. PrPres was finally detected by western blot. Films were then transformed into digital pictures, signal intensities were quantified and regression models were computed.
According to the results obtained, scrapie agent showed higher stability than BSE in all the environments studied. However, no significant differences were observed among mouse-passaged scrapie strains and sheep scrapie. The regression models provided t90 and t99 values (times of incubation necessaries for 90% and 99% reduction of PrPres levels). In urban sewage, i.e., t99 was estimated as about 50 and 22 days for scrapie and BSE respectively. In general, the effect of the matrix was clearly observed in all the experiments, showing up to a 6-8 fold higher reduction of PrPres levels in comparison to PBS controls.
As some of the inocula were titrated in terms of infectious doses, we approximated the decay of PrPres levels to the reduction of infectivity for both agents. In slaughterhouse wastewater, i.e., two-log reduction was observed for both agents after 30-35 days of incubation. Data on infectivity will be confirmed by a series of bioassay experiments.
AD C. Maluquer de Motes, R. Girones, University of Barcelona, Spain; J.M. Torres, Centro de Investigación en Sanidad Animal, Spain; M. Pumarola, Autonomous University of Barcelona, Spain
SP englisch
PO Schottland