The Brazilians and Argentines understand the conditions under which this organism does well (requiring long periods of free water on the leaf overnight, etc).  We don't have those in the U.S., except maybe along the Gulf Coast -- sorta.

Here's a short article on it -- note the publication date (March '05) was precisely during the timeframe that nearly all the other farm publications in the U.S. were preparing us for an epidemic onslaught.