As the first cases of swine flu outside North America were confirmed Monday in Spain and Scotland, European health officials issued a series of contradictory public warnings and vacillated over whether it was safe to travel to the United States or Mexico.
In Luxembourg, Androulla Vassiliou, the European Union's health commissioner, told reporters she was "not worried at this stage" about a global pandemic spreading to Europe but nonetheless urged all travelers to avoid the United States and Mexico "unless it is very urgent for them."
The statement prompted a rebuke from U.S. health officials, who said there was no need to impose a ban on travel to the United States, where 40 cases of swine flu -- none of them fatal -- have been diagnosed. Richard E. Besser, acting director of the Centers for Disease Control and Prevention in Atlanta, called the E.U. travel warning "quite premature."
Vassiliou later backtracked and said she was simply advising Europeans to avoid "unnecessary travel" to areas in North America where there have been "serious outbreaks" of swine flu in humans.
"People should use their common sense," she told the BBC. "It's unreasonable to ban traveling, or to even advise travelers not to go to, let's say, Chicago or other places where there are no outbreaks. It's only that people should be more careful before they leave."
The European Union said it would hold an emergency meeting of health ministers from its 27 member countries to coordinate a response to the spread of swine flu. The meeting, however, is not scheduled to occur until Thursday.
Meanwhile, individual European countries have issued a melange of travel and health advisories, with some warning against travel to Mexico but others playing down the risk.
Robert Madelin, the European Union's director-general for health and consumer protection, said it was imperative for European countries to fashion a united response.
"If we do not coordinate, individual regions and countries take measures which are inconsistent and create huge economic and personal costs," he told reporters in Brussels.
In Germany, the foreign ministry issued an advisory Monday against nonessential travel to Mexico. It urged the public to monitor conditions in the United States but did not warn against travel there.
Two large German tourism companies, TUI and Thomas Cook, canceled flights to Mexico City until at least next week. They told customers it was still safe to travel directly to Mexican beach resorts, for the time being.
Officials at Frankfurt and Munich international airports, two of Europe's busiest, distributed swine-flu informational leaflets and instructed employees to watch for passengers who might be infected.
"I think we can assume that we will see the virus here soon," Michael Pfleiderer, a German government virologist, told Bavarian radio. "But that does not mean that we should paint the whole picture dark or even black." He said that normal hygiene measures were sufficient to guard against the virus and that local health agencies were well prepared.
In Spain, health officials confirmed that a 23-year-old university student who returned from Mexico last week had tested positive for the virus. The patient has been isolated in a hospital ward in the town of Almansa since Saturday, but his condition is not serious, said Trinidad Jimenez, the Spanish health minister.
Spanish officials said they were treating 20 other suspected but unconfirmed cases, all involving people who recently traveled to Mexico. Suspected cases were also reported in France, Sweden, Germany and Switzerland.
In Scotland, Health Secretary Nicola Sturgeon said late Monday that two people who returned Friday from Mexico had tested "conclusively" for swine flu. Officials said the two patients were being kept in isolation in a hospital in the town of Airdrie and were expected to recover.
Seven people who had been in contact with the travelers have displayed mild flu symptoms but are not being hospitalized, Sturgeon said. "We remain very encouraged by the fact that outside Mexico everyone who has contracted swine flu has experienced mild symptoms only," she said.
British officials said a Canadian tourist visiting Manchester also was suspected of having swine flu after a general test for influenza came back positive. Health officials are investigating 14 other cases involving people with flu-like symptoms who recently traveled to the United States or Mexico. None are hospitalized, however, as they undergo further tests.
British Health Secretary Alan Johnson told the House of Commons that the government had a stockpile of 33 million doses of flu vaccine, enough for about half the United Kingdom's population. He said the government had been building up stockpiles against a potential flu pandemic for the past five years.
Johnson said the government had stepped up health checks for passengers arriving in the United Kingdom. Passengers on planes from Mexico have been questioned by a doctor before being allowed to leave the aircraft.
Correspondent Kevin Sullivan in London contributed to this report.