(AP) - The federal government is preparing a travel advisory instructing Americans to avoid nonessential travel to Mexico, the acting head of the Centers for Disease Control and Prevention said Monday.
Dr. Richard Besser made the disclosure during a news conference in Atlanta, saying the advisory was being released "out of an abundance of caution."
Besser also reported 40 confirmed cases of swine flu in the United States, including 20 in New York City. He said people can help keep the disease from spreading by taking everyday precautions such as frequent handwashing, covering up coughs and sneezes, and staying away from work or school if they're not feeling well.
Before the CDC changed its advice to travelers, U.S. airlines were reporting that some passengers have already changed or canceled their plans to fly to Mexico.
Spokespeople for US Airways, American Airlines and Delta Air Lines said Monday passengers have requested travel changes, but none of the carriers would say how many.
The three airlines said their operations are proceeding as normal and they have not canceled any flights to Mexico as a result of the scare.
"The loads are a little bit less than they normally would be for this time of day, but we are not seeing mass bookings away," said Michelle Mohr, a spokeswoman for US Airways.
The carrier does not fly nonstop from Europe to Mexico, but it does offer European travelers the ability to connect to Mexico through U.S. airports.
The top European Union health official urged Europeans on Monday to postpone nonessential travel to parts of the United States and Mexico because of the swine flu virus.
American Airlines spokesman Tim Smith said his carrier has not had a lot of requests for travel changes, though there have been some.
Delta continues to follow CDC and government agency recommendations, spokesman Anthony Black said.
"We have seen minimal changes to customer bookings," he said.
Several airlines are allowing passengers to change their travel plans to or from Mexico without any fee or penalty.
Airline stocks, meanwhile, were pummeled Monday. Shares of Delta, US Airways and American parent AMR Corp. were down double-digit or high single-digit percentages in midday trading in New York.
Merrill Lynch analyst Michael Linenberg said in a research note Monday that news of Mexico's outbreak of deadly swine flu is likely to pressure U.S. airline stocks in the near-term as investors fear a replaying of Asia's SARS episode, which impacted the global sector in the spring of 2003.
"Airlines with large international operations, especially to/from Mexico, are likely to be perceived by the market as having the most downside risk in the event that the swine flu becomes a pandemic," Linenberg said.
(Copyright 2009 by The Associated Press. All Rights Reserved.)