The likelihood of a human flu pandemic is very high, U.S. Health and Human Services Secretary Michael Leavitt said as he began a tour of Southeast Asia to coordinate plans to combat bird flu.
The H5N1 strain of bird flu has swept through poultry populations in many parts of Asia since 2003 and jumped to humans, killing 60 people, mostly through direct contact with sick fowl.
While there have been no known cases of person-to-person transmission, World Health Organization officials and other experts have been warning that the virus could mutate into a form that spreads easily among people. In a worst-case scenario, they say millions of people could die.
Three influenza pandemics have occurred over the last century and "the likelihood of another is very high, some say even certain," Leavitt said Monday after meeting with Thai health officials to review the country's preparations against the disease.
"Whether or not H5N1 is the virus that will ultimately trigger such a pandemic is unknown to us," he told a news conference.
"The probability is uncertain. But the warning signs are troubling. Hence we are responding in a robust way."
Leavitt, accompanied by the director of WHO and other top health professionals, also plans to visit Laos, Cambodia and Vietnam to prepare for the anticipated public health emergency.
His tour comes after U.S. President George W. Bush last month established the "International Partnership on Avian and Pandemic Influenza" to coordinate a global strategy against bird flu and other types of influenza.
Leavitt said "containment" was the first line of defense against the illness, encouraging countries to step up development and production of vaccines and strengthen efforts to detect any cases of human-to-human transmission early.
"Anywhere, the sooner we know, the faster we can respond and the more lives that will be saved," he said.
Thai Public Health Minister Suchai Charoenratanakul said Thailand would contribute at least 5 percent of its antiviral drug supplies to a proposed Southeast Asian regional stockpile.
So far, 41 people have died of bird flu in Vietnam, 12 in Thailand, four in Cambodia and three in Indonesia. Leavitt said he would also visit Indonesia at a date to be announced.
World Heath Organization Director General Dr. Lee Jong-wook said preparation was the key to preventing a flu epidemic such as the one that struck in 1918, killing an estimated 40 million to 50 million people.
"Now we know in advance what is happening and we have to prepare ourselves. That is our duty," he said.