Avian flu risk low for tourists, but experts fear virus mutation

As temperatures remain cool in Asian countries, the Centers for Disease Control and Prevention in Atlanta predicts more outbreaks of avian, or bird, flu among poultry there. Although the current outbreak is not considered risky for most tourists, epidemiologists are worried the viruses could mutate and acquire the ability to spread efficiently from person to person.

Last month, the CDC elevated its outbreak notice on avian influenza to a travel health precaution because the disease had spread in Vietnam. As of press time Tuesday, 60 human cases of avian flu had been diagnosed in Cambodia, Thailand and Vietnam, including 43 deaths. So few cases may not seem like cause for alarm, but health experts worldwide fear that if the avian flu virus and a human influenza virus were to simultaneously infect a person, it could form a new, mutated virus.

“And the new virus might acquire the ability to spread easily person to person in a sustained manner” and result in a global pandemic of the H5N1, the strain of bird flu now occurring, says Dr. Tim Uyeki, an epidemiologist with the CDC influenza branch.

“An influenza pandemic occurs when a new influenza virus appears against which the human population has no immunity, resulting in several, simultaneous epidemics worldwide with enormous numbers of deaths and illness,” according to the World Health Organization.

For now, the risk for most tourists to Asia is minuscule, especially if they take simple precautions and aren’t exposed to infected poultry.

Travelers shouldn’t cancel their plans, Uyeki says. “There are no travel restrictions. We aren’t saying, ‘Don’t visit those countries.’ The situation right now is that H5N1 is going from poultry to people, and in a small number of cases there has been probably limited person-to-person transmission.”

The viral infection typically strikes wild birds but can also affect chickens and other poultry. Humans are infected when exposed to sick birds, uncooked poultry or contaminated surfaces, the CDC says.

Symptoms include fever, cough and sore throat. The infection in people is often fatal, and no human vaccine is available. The human influenza vaccine offers “zero protection” against H5N1, Uyeki cautions.

The first documented human infections were in Hong Kong in 1997, WHO reports. In that outbreak, 18 people were hospitalized and six died.

“There has not been one case in an American,” Uyeki says. “The risk for an American who is going to these countries of getting infected with H5N1 is extremely low. It is extremely unlikely unless they are ... having direct contact with a sick or dead [infected] chicken or duck or drinking raw duck blood, a delicacy in Vietnam. Avoid any contact with poultry, period.”

For other recommendations, see the CDC website for travelers, www.cdc.gov/travel.

An Orange County physician agrees with Uyeki. “There are so few human cases that I don’t think restricting travel is an issue yet,” says Dr. Cherie Hinchliffe, a Laguna Beach internist who specializes in travel medicine. She tells her patients, “Stay away from farms and open-air markets. Avoid domesticated birds. Stay away from zoos and aviaries.”

If you are taking children, she adds, supervise their hand washing “because they are usually poor hand washers and often have their hands in their mouths.” If you are ill, cancel the travel plans, she says. “It might make you more susceptible.”

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Healthy Traveler appears every other week. Readers may e-mail travel health concerns or questions to Kathleen Doheny at kathleendoheny@earthlink .net