It will take more for avian flu to spread rapidly among people. The current H5N1 strain would have to acquire genetic material from a human flu bug in a process called re-assortment. The worst fears of public health experts could come true if a person caught both flu strains at the same time. Scientists, however, have demonstrated that this mixing of strains could also occur in other mammals, notably pigs. Ominously, the Asian swine population has also increased significantly.
It could be the gathering of a perfect storm: dense concentrations of chickens, pigs, aquatic birds and people. "It's clear that Southeast Asia poses the greatest risk today of a new virus unfolding and coming forward as a pandemic strain," said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. "Darwin could not have created a more efficient re-assortment laboratory if he tried."
Prathum Buaklee feeds some of the chickens that have brought prosperity to him and many other Thai farmers.
(Alan Sipress -- The Washington Post)
_____Avian Flu Facts_____
Q. What is avian flu?
A. Avian influenza is an infectious disease of birds caused by type A strains of the influenza virus. The disease, which was first identified in Italy more than 100 years ago, occurs worldwide.
Q. Is avian flu contagious?
A. Yes. All birds are thought to be susceptible to infection with avian influenza, though some species are more resistant to infection than others. The first documented infection of humans with an avian influenza virus occurred in Hong Kong in 1997, when the H5N1 strain caused severe respiratory disease in 18 humans, of whom 6 died.
Q. What are the symptoms of avian flu?
A. Published information on human infection is limited to studies of the 1997 Hong Kong outbreak. Symptoms included fever, sore throat, cough and, in several of the fatal cases, severe respiratory distress secondary to viral pneumonia.
Q. How do you treat avian flu?
A. The quarantining of infected farms and destruction of infected or potentially exposed flocks are standard control measures aimed at preventing spread to other farms and eventual establishment of the virus in a country’s poultry population.
Q. How can you protect yourself against avian flu?
A. Workers involved in the culling of poultry flocks must be protected, by proper clothing and equipment, against infection. These workers should also receive antiviral drugs as a prophylactic measure.
Q. How effective is the vaccine?
A. Vaccination of persons at high risk of exposure to infected poultry, using existing vaccines effective against currently circulating human influenza strains, can reduce the likelihood of co-infection of humans with avian and influenza strains.
• WHO Fact Sheet
• CDC: Avian Flu Information
Source: World Health Organization
Counting on Good Fortune
U.N. and other agriculture experts say the cost of adopting simple safeguards is low but requires a change in attitude, as happened in the United States and Europe when they went through their own chicken revolutions nearly four decades ago.
The dramatic increase in poultry production on both sides of the Atlantic was fueled by rising incomes after World War II, rapid urbanization and technical breakthroughs.
The U.S. Department of Agriculture launched an aggressive campaign to educate farmers about safety, said Carol Cardona, a poultry veterinarian at the University of California at Davis. Farmers, who realized they had much to lose if disease broke out, readily adopted the measures, she said.
Nirundorn Aungtragoolsuk, director of disease control in the Thai department of livestock development, said his government recently adopted strict regulations for large, export-oriented chicken farms. But the rules do not apply to most Thai farms.
"They have done it their way for a long time and we cannot change it overnight," Nirundorn said, adding that his department was too understaffed to enforce requirements.
Prathum admitted he was counting on good fortune to avoid a bird flu outbreak among his flock. "I'm still scared, but what can I do?" he said. "We'd never had bird flu before. It just came."
He acknowledged that his sons had been encouraging him to adopt modern safeguards. His older son, the student of veterinary science, had been particularly outspoken. "I may not be able to learn about these as fast as young people," Prathum said. "I'll retire after a while and pass the farm on to my son. Then he can do what he wants."