SEOUL — Scientists are trying to determine if avian flu has become endemic in South Korea’s wild birds, meaning it’s a threat year-round and not just during the winter migratory season, a U.S. military health official said Monday.

Health workers have confirmed two cases of the H5N1 virus in Seoul in the past week and a half. Other cases have been confirmed throughout the rest of the country in recent weeks.

In Japan, a small outbreak of avian flu occurred near Misawa Air Base several weeks ago.

"Are we just going to have to live with H5N1 in the area?" said Lt. Col. Eric Lund, a U.S. Forces Korea preventive medicine consultant. "Every time we go to the zoo, we say to our kids, ‘Don’t touch the birds,’ but this time we’ll really mean it."

The Associated Press reported Monday that South Korean officials said they had killed all 15,000 poultry in South Korea’s capital and will prevent live poultry from being brought into the city.

Lund said South Korean officials have found avian flu in 35 locations in the past six weeks, compared to 7 locations in approximately 100-day period in 2006 and 2007.

In 2003, the virus spread to 19 farms in about 100 days, he said. Both previous outbreaks occurred during the winter, when migratory birds from Russia and China come to South Korea.

"That’s why it’s a surprise to everyone, veterinary-wise." Lund said. "It’s come back at the end of March and April, and it’s spread so quickly to so many places in such a short period of time."

The virus typically spreads from migrating birds to domestic chickens, ducks, turkeys and other fowl. Lund said the virus is only a threat to humans who work closely with birds and are in contact with their feces, saliva or other fluids.

Humans rarely transmit the disease to one another, and there are no known cases of a human contracting it in South Korea. A South Korean soldier suspected of having the virus was determined not to have it, Reuters reported on Friday.

Lund said four groups at USFK most at risk for catching the disease are being watched closely: public works employees who pick up dead birds, veterinarians, hospital workers and microbiologists who handle samples that could contain H5N1.

"They’ve got some serious bad stuff inside that test tube," Lund said.

The "really, really big" concern is that H5N1 could spread from a bird to a human who already has the human version of the virus, he said. If the two viruses mix, they could form a new superbug that could spread more easily.

"If and when that happens, the question is, how transmissible is that thing, human to human?" Lund said. "All over the world, governments are working real hard to try to prepare for it. Everybody thinks it’s a matter of when."

A H5N1 vaccine has been developed but isn’t considered effective against new strains of the virus.

The Associated Press reported the South Korean government plans to double its supply of the drug Tamiflu by the end of the year, from enough to treat 1.23 million people to 2.5 million. About 48 million people live in South Korea.

Lund said USFK has adequate supplies of Tamiflu to treat an outbreak. The 121st Combat Support hospital got a high-speed lab test last week and can make a tentative diagnosis of H5N1 in humans in four to six hours. Lab tests previously had to be shipped outside South Korea for diagnosis.

The test has not been used yet, Lund said.

For now, people need to make sure they have an updated flu shot and stay away from wild birds. When they get flu-like symptoms — a cough, fever, muscle aches, trouble breathing — they should ask themselves if they’ve been in close contact with birds or a human known to have the disease.

USFK officials have said chickens and eggs sold at the commissary are safe to eat, and are chickens and eggs sold off-post are safe if cooked.

"It’s a risk if you put yourself at risk, but otherwise you go about your business normally," Lund said.

Sign Up for Daily Headlines

Sign up to receive a daily email of today's top military news stories from Stars and Stripes and top news outlets from around the world.

Sign Up Now