Selected pieces of wax-embedded spinal cord tissue from the sentinel animal were extracted and postfixed in 2.
Results of Metagenomic and Phylogenetic Analysis of BoAstV-NeuroS1 in Sentinel Animal
On May 3, 2007, the first sentinel animal in the program (4-year-old Holstein Friesian cow, North-Rhine Westphalia, Germany) tested positive for BTV antibodies and genomes in a regional laboratory (Krefeld, Germany).
Because of the low number of sentinel animals in 2007, or double-tested cattle destined for export in January and February 2008, substantially more new infections may have occurred in winter 2007 and early spring 2008.
dagger]) Day 0 was defined as the day the sentinel animals
arrived at the farm in Nyakatonzi (Kasese District).
Sheepdogs that lived in the study areas were also used as sentinel animals
Virus isolations from sentinel animals
and genetic characterizations of these strains indicated continuing circulation of a subtype IE genotype, which was isolated from equines during the recent VEE outbreaks.
These findings in turn raised questions about factors involved in human susceptibility, risks of pesticide exposure, efficacy of mosquito control, the value of sentinel animals
in surveillance, and the roles played by various species in virus transmission and amplification.
These data include reports of WNV-infected mosquitoes, sentinel animals
, dead birds, and ill humans and horses (5).
Captive sentinel animals
, compared to all other arbovirus surveillance systems, provide more precise data on the location and time in which virus transmission has occurred.