And The Early Show National Correspondent Hattie Kauffman reports one way people are getting there is on a ship known as the "flu ferry."
From the very young to the very old, Kauffman reports, people are getting to a pier before dawn, boarding the ferry that will guarantee them a flu shot once they reach Canada.
"Normally," says Kauffman, "the cruise between Seattle and Victoria, British Columbia, would be empty at this time of year. But the flu cruise has the boat completely sold out, and more runs have been added."
Ever since the Victoria Clipper announced its flu shot special ($105 round trip, including the shot), phones have been ringing off the hook.
"We're getting calls from people in Arizona, Iowa, Colorado," exclaims Darrell Bryan, general manager of Clipper Navigation.
To passenger Marlaina Lieberg, who is both blind and asthmatic, the trip is something to celebrate: ""I'm just not willing to take the risk of standing in a line and getting up to the front and having them say, 'Sorry, we don't have any!'"
Cruising into Victoria Harbor means instant relief, Kauffman notes. Just off the boat, right next to Customs, is the impromptu flu clinic.
"I'm very relieved, because the doctor said I absolutely had to have (a flu shot)," Sherry Thun told Kauffman. "He said, 'I don't care how you get it, just get it.'"
It was nurse Shirley Connelly's idea to offer some of the surplus flu shots to Americans traveling on the ferry. "It isn't political," says Connelly, who works for Vancouver Island Vaccines. "It's just humanitarian."
"Do you have any concern that the floodgates are opening, that people might be thinking, 'Oh, we can all go to Canada'?" Kauffman asked.
"Yes, there's concern," Connelly replied. "It isn't endless. It's not an endless supply. But we're managing for now."