Hasn't happened yet, so I don't worry about it. The biggest cases of widespread milk poisoning have been from commercial pasteurized milk, not small production raw milk, just to put the persecution from the dairy board in perspective. Here is an interesting quote from someone in support of pasteurization:
"Many bacteria are not killed by pasteurization. Rod-shaped
bacteria form a "spore" at the first sign of heat ("spore"
is the Greek word for "seed"). When the milk cools, the
spore re-emerges into its original form."
"Since 1973, 394 cases of salmonella have been
reported in Los Angeles County. Of these, 101 (25.6%)
were consumers of raw milk. Molecular fingerprinting
identified the strain of bacteria in ill persons as
the same as that found in raw milk samples."
Compare those figures and facts to the info in this article:
http://www.townsendletter.com/Oct_2002/milk1002.htm