What I'm gathering is there's a breakdown in communication between medical/lab types and law enforcement types. Not surprising, they speak entirely different languages, and we haven't been testing everything in sight for Anthrax before.
http://www.msnbc.com/news/643295.asp
"ANTHRAX is a member of the large Bacillus family of bacteria. So are germs that cause mild food poisoning and others that are harmless to people. Emergency workers checking suspicious letters like the one Senate Majority Leader Tom Daschle got Monday can do quick tests to determine if signs of the large Bacillus family exist to give reason to worry about anthrax. But this rapid first test is very often wrong because it cannot tell if B. anthracis, the specific anthrax germ, is the culprit or if less harmful Bacillus bugs are present, say biologists."