Travel advisory Published April 30, 2009 ELMENDORF AIR FORCE BASE, Alaska -- Based on the increase in health risk, posed to military personnel traveling to Mexico, the commander of U.S. Northern Command has determined that official travel for U.S. military personnel to Mexico should be restricted to mission essential personnel travel only. A process has been established to accommodate special situations. The commander of U.S. Northern Command has taken this action to minimize risks to U.S. military personnel.