First Mad Cow Disease, then the Avian Bird Flu, now the Swine Flu?

What is with all these diseases being contracted from all these animals? First we had to worry about the mad cow disease. Then, a couple years ago, it was the Avian Bird Flu. Now, the pigs are getting in on it. Why don't we just spread the wealth to all the farm animals- horses, sheep, geese, and on my grandpa's farm, emu's. I am not trying to sound like I am making a joke out of it because I am taking it seriously and aware that it has the potential to turn into another possible pandemic. I just think it's so weird how all these crazy fatal diseases are being contracted through farm animals. The depressing thing is that they are saying that the people in Mexico that got it were in their 20's, 30's and 40's. I guess the best thing we can do to prevent ourselves from getting the Swine Flu is do we do to keep ourselves from getting infected with any other kind of sickness- washing your hands, not touching your face, etc.