Concerns Over Avian Flu Take Flight As Cases Spread in Southeast Asia by Gina Shaw Move over severe acute respiratory syndrome (SARS), thereís a new virus on the block: avian influenza, or "bird flu." As of press time, the outbreak of the disease in Southeast Asia has hit Vietnam, Thailand and Malaysia. According to the World Health Organization, Vietnam and Thailand have had 40 confirmed human cases of avian flu this year, with 29 deaths as of Sept. 9. Malaysia has isolated two people thought to be infected, a 10-year-old boy and a veterinary official. Actually, avian influenza isnít all that newóitís been around for more than a century, and the first documented case of the disease making the jump from poultry to humans occurred in 1997 in Hong Kong. But the latest mutation to appear in humans, known as H5N1, has caused more cases than any other previous human outbreak, which has scientists worried about a global pandemic. Thatís because H5N1 is one of several bird flu subtypes that are classified as "highly pathogenic," meaning that they are very contagious and rapidly fatal. (The 1997 Hong Kong outbreak, which killed six of the 18 people infected, was a close cousin.) Thereís currently no vaccine desi gned to attack avian flu and because itís primarily a disease of birds, the human immune system has no natural ability to fight it off. The advantage we currently have against H5N1 and other types of avian flu is that the disease doesnít seem to be able to be transmitted from one person to another. So far, all cases of the virus in humans have been traced to some form of contact with an infected bird, such as handling the bird itself or being exposed to its feces. But if it were to mutateópossibly by interacting with a human influenza virusóand become able to jump from human to human, the results could be deadly. "Such a catastrophe has yet to occur, but is one of the major fears of infectious disease experts throughout the world," wrote the editors of the British medical journal The Lancet in an editorial published in January. "In view of the high mortality of human influenza associated with this strain, the prospect of a worldwide pandemic is massively frightening." "Weíre all holding our breath," agreed Dr. Julie Gerberding, director of the Centers for Disease Control and Prevention. In August, the CDC released a draft of a national pandemic preparedness plan aimed at controlling a mutant flu outbreak if one does occur. The plan predicted that a worst-case scenario could involve as many as 207,000 deaths. (To put that in perspective, about 36,000 people die of regular flu in the United States every year.) At the top of the preparedness menu were new vaccines. The National Institutes of Health has funded trials of two experimental vaccines that may clip the wings of bird fluówith one that targets H5N1 and another aimed at its Hong Kong relative, H9N2. The CDC is also increasing international flu surveillance in the hopes of providing an early warning on outbreaks of any new strains. Poultry farms all over Southeast Asia are being culledóan approach that many believe kept the 1997 Hong Kong outbreak from becoming far worseóbut what else can be done to help prevent H5N1 or another of its family members from mating with a human flu strain and causing an epidemic? Key measures, according to the World Health Organization, will involve protecting people at high risk of exposure to infected poultry with proper clothing, protective equipment, anti-viral drugs and flu vaccines. Although the existing influenza vaccines donít prevent avian influenza, they can reduce the likelihood that a poultry worker will develop human flu and bird flu at the same timeóthe situation that could lead to a new, deadlier strain. On a more personal level, how can you steer clear of avian flu? Fortunately, thereís no evidence to date that human cases of the disease have been transmitted by eating poultry products, so you donít have to swear off roasted chicken. Like other food-borne pathogens, H5N1 and other forms of bird flu virus are killed off by adequate heat, so as always, be sure to cook all poultry and poultry products (including eggs) thoroughly before eating. When handling raw poultry or eggs, be sure to wash your hands and all food preparation areas and utensils thoroughly. And in case youíre still worried, the CDC has banned poultry imports to the United States from countries with avian flu outbreaks. Gina Shaw is the medical writer for The Washington Diplomat. Avian Flu Tips for Travelers If youíre traveling to an area infected by the avian influenza, the Centers for Disease Control and Prevention recommends the following precautions: - Avoid poultry farms - Keep away from animals in live food markets - Steer clear of any surfaces that may have been contaminated with feces from poultry or other animals - Wash your hands often, using either soap and water or antibacterial hand rubs (itís a good idea to keep a bottle of Purell hand sanitizer handy) If you return from an infected area and notice respiratory symptoms such as fever and coughing, see your doctor immediately and be sure to provide a complete travel history. óGina Shaw