Joel,Interesting observations in NWC. Just started looking at hygienic behavior as a defense against V. Though this will probably take several mech. of defense to knock, as well as some time. Please be patient. We've been concentrating efforts on Tracheal mites up to this point. Counts are almost undetectable in the breeders coming out of winter this year with no treatment. Susan Cobey Ohio State University Dept. of Entomology 1735 Neil Ave. Columbus, OH 43210 Tel.(614) 292-7928 Fax (614) 292 2180