Known for speaking freely, Biden told NBC's "Today" show on Thursday that he had urged family members to avoid airplanes and subways for fear of contracting the H1N1 flu virus.
"I wouldn't go anywhere in confined places now," Biden said.
The comments infuriated the travel industry and triggered several revisions from the Obama administration, whose official advice is less severe.
Homeland Security Secretary Janet Napolitano commented, "If he could say that over again, he would say if they're feeling sick, they should stay off of public transit or confined spaces."
By Friday night, Biden seemed ready for his own do-over. A longtime rider of Amtrak, he took a train from Union Station to his Delaware home, his office said.