is a direct link to the update on the CDC page. As it is an update, it is highly possible that the last sentence was added after f-mattox referenced it -- perhaps one of those daily updates mentioned earlier.
Nowhere in the current release does it say that more than 12% of pax currently onboard are suspected to have symptoms consistent with norovirus -- it just says "higher than expected" levels, whatever that means.
In any case, I wouldn't be concerned about your cruise on March 9. By looking further into the site, I found this
, indicating that I was on a ship soon after a norovirus (and e.coli) incident a couple of weeks prior, and we had no issues.
Just take the usual precautions yourself. Remember, it's also possible to contract norovirus just about anywhere. One of our huge, respected teaching hospitals in Boston just reported an outbreak in one of its wards.