White House spokesman Robert Gibbs said:
"The president’s trip to Mexico has not put his health in any danger. The incubation period is 24 to 48 hours and we have been back from Mexico for nine days now. The doctors say he was not at risk."
On Sunday, the DHS announced that the U.S. has declared a public health emergency over the swine flu.
This flu, while sickening 20 in the U.S., has killed at least 20 in Mexico with 61 more suspected. No one in the U.S. has died.
The flu is a unique combination of avian, human, and swine flus.