I have an update from the Center for Disease Control:
CDC Travel Health Warning for Novel H1N1 Flu in Mexico Removed
Updated: May 15, 2009
CDCís Travel Health Warning recommending against non-essential travel to Mexico, in effect since April 27, 2009, has now been downgraded to a Travel Health Precaution for Mexico.
CDC has been monitoring the ongoing outbreak of novel H1N1 flu in Mexico and, with the assistance of the Mexican authorities, has obtained a more complete picture of the outbreak. There is evidence that the Mexican outbreak is slowing down in many cities though not all. In addition, the United States and other countries are now seeing increasing numbers of cases not associated with travel to Mexico. Finally, the risk of severe disease from novel H1N1 virus infection now appears to be less than originally thought.
At this time, CDC has removed its recommendation that U.S. travelers avoid travel to Mexico.
CDC continues to recommend that travelers visiting Mexico take steps to protect themselves from getting novel H1N1 flu.
CDC recommends that travelers at high risk for complications from any form of influenza discuss with their physicians the risks and benefits of travel in the context of their planned itinerary to Mexico, and may want to consider postponing travel.
It goes on to list categories of at-risk people. No AR15 racers passing a physical exam would be at-risk.
So this means that AR15 could safely visit Mexico.