S.C. steps up efforts to prepare for avian flu
Testing, surveillance on rise
By LINDA H. LAMB
llamb@thestate.com
The most lethal strain of bird flu probably won’t wing its way to the United States through South Carolina. But if it does, health and wildlife officials here don’t want to be sitting ducks.
There’s a flurry of activity to increase surveillance and testing in places where poultry is raised and sold — and in migratory birds, especially waterfowl, that are viewed as one of the most likely ways avian influenza might enter the country.
“Our emphasis is, you have to get it at the source, and the source is birds,” Andrea Morgan, associate deputy administrator for veterinary services for the U.S. Department of Agriculture, told a Pandemic Influenza Summit in Columbia last month.
Efforts in S.C. include:
• The Clemson University Animal Diagnostic Center in Columbia has increased avian-flu testing of poultry, including the state’s 631 chicken farms.
• The state veterinarian’s office has used federal money to hire extra employees to do surveillance and testing at about 20 auctions and flea markets around the state where live birds might be sold.
• Department of Natural Resources officials are making plans for surveillance and testing of migratory waterfowl when they return to South Carolina in the fall. Hunters and large hunt clubs might be asked to be part of the effort to monitor wild birds for possible signs of illness.
State officials hope to receive at least $3 million in new federal money to help with pandemic-flu preparations. Half of that money, a grant of $1.5 million, was announced at the recent summit.
Checking birds is viewed as an important part of planning for a pandemic — an outbreak that affects the whole world — because a potentially lethal strain of flu could show up in birds first.
DEADLY POTENTIAL
Birds can be affected by hundreds of flu viruses, some of which do little more than ruffle their feathers. The virus you’ve heard about in recent months, however, is a lethal strain of the H5N1 virus that can kill a bird within 48 hours.
Worldwide, more than 100 people have died, most in Asia, after close contact with birds that carried this virus. According to the World Health Organization, the virus is hardy as well as lethal, able to survive in bird feces for at least 35 days at low temperatures and six days at higher temperatures.
At some point, the virus probably will be found in a bird or a flock in North America, U.S. Health and Human Services Secretary Mike Leavitt told the recent summit.
That won’t necessarily be a disaster, he said. So far, the virus has not taken a form that spreads between humans.
What Leavitt and others are trying to prepare for is the possibility that the lethal strain of H5N1 might mutate into a form that does spread readily from person to person.
That, they fear, could cause a flu pandemic like the one in 1918 that infected one in four Americans and killed an estimated 40 million people worldwide.
“It’s important to know that this isn’t just the flu,” Leavitt said. “It’s an aggressive killer when it occurs.”
But he noted that it’s hard to balance the need to inform people about pandemic possibilities with the need to stay calm and realistic. Some people panicked about the respiratory ailment SARS in 2003, for example, yet the disease was contained and never made it to South Carolina.
“The problem is that everything you say before a pandemic sounds alarmist,” Leavitt said. “Then everything you say after a pandemic sounds inadequate.”
On the national level, health officials are working to develop an effective avian-flu vaccine. There’s also a goal to buy 20 million doses of antiviral drugs that could help treat people who became ill. So far, 620,000 doses of these drugs have been designated for South Carolina.
The $7.1 billion federal avian flu campaign also stresses the need for states and communities to make plans for the possibility of a pandemic. South Carolina’s counties and major cities will have to draw up plans for how they could handle a pandemic, said Dr. Jerry Gibson, state epidemiologist.
ROLE OF MIGRATION
Meanwhile, agriculture and wildlife experts focus on birds.
There is evidence migratory birds have spread the lethal virus, with waterfowl seen as the primary culprits. Surveillance efforts already have been ramped up in states such as Alaska and California where flyways could include visitors from Asia.
Morgan said, since 1998, her department has tested more than 12,000 migratory birds in the Alaska flyway alone.
Since 2000, almost 4,000 migratory birds have been tested along the Atlantic flyway, which includes paths that go through South Carolina, she said. This spring, federal plans call for testing 75,000 to 100,000 migratory birds nationwide.
DNR and the Department of Agriculture are working on plans to spot-check waterfowl — such as ducks, geese and red knots — that make layovers in South Carolina.
Birds that winter here usually take off in March and April for nesting areas in Canada and the upper United States, said Derrell Shipes, wildlife biologist with the S.C. Department of Natural Resources.
“The ones that we’re really interested in have all departed now,” Shipes said. “But we’ll be ready when they come back.”
In the fall, Shipes and Morgan said, bird hunters might be asked to help. Their vigilance could supplement other surveillance efforts, and some testing could be done in birds during routine check-ins by hunters in wildlife management areas.
Officials also might seek the cooperation of people who hunt ducks on land owned by private hunt clubs. Shipes said most of the clubs are in remote areas of Beaufort, Charleston and Georgetown counties.
Experts say it is rare for migratory birds to pose any direct risk to humans. The worry is they could come in contact with and possibly infect domestic birds, as apparently has happened in Asia, Europe and Africa.
“If we find a migratory bird that’s positive, what we would do is ... look for commercial operations, backyard operations that are in the vicinity of that find, and then we would do testing,” Morgan said.
POULTRY TESTING
The poultry industry has a well-established system of testing, having encountered lethal avian flu outbreaks before, Morgan said.
For example, she said, an outbreak of a highly pathogenic avian flu in 1983 (an H5N2 strain) resulted in the destruction of 17 million chickens in Pennsylvania and Virginia.
Tony Caver, South Carolina’s state veterinarian, said surveillance has been increased at auctions and flea markets where live birds such as chickens and ducks might be sold periodically. Also, at an upcoming meeting, state officials will brief farmers of free-range birds about the need to increase awareness and security.
Flocks here are not particularly at high risk, Caver said. “But we take it very seriously because of the poultry industry in South Carolina and because of the public-health implications of that particular strain.”
Broiler, egg, chicken and turkey production was a $662 million business in the state in 2003, including 200 million chickens produced for S.C. dinner tables.
So far in fiscal 2005-06, the Clemson University Animal Diagnostic Center has done more than 4,850 bird-flu tests on samples from poultry farms and backyard flocks, Caver said. This compares with 6,018 tests in all of fiscal 2004-05 and 1,238 tests in 2003-04.
LOCAL, GLOBAL ISSUES
Shipes said he is concerned about “all of this hype creating additional reports of dead birds.” However, large numbers of dead or sick birds should be reported.
There’s a lot that scientists still don’t know about the patterns of avian flu globally, Shipes said.
For example, a dead swan found on the cost of Scotland in late March was found to carry the highly pathogenic form of the H5N1 flu virus. But scientists, ornithologists and veterinarians in Great Britain still are trying to work out where the swan originated and where it came in contact with the virus.
Gibson and other health experts say the lethal strain of bird flu is just one virus that might — or might not — mutate to pose a serious threat to humans at some point.
“Sooner or later there will be a substantial epidemic again, but as with a hurricane, we don’t know when and where it might strike,” Gibson said.
Besides the 1918 pandemic, there were two others in the 20th century — causing about 2 million deaths in 1957 and 1 million in 1968.
Ideally, Gibson said, as with outbreaks of smallpox and polio, the World Health Organization would follow established plans to contain an outbreak at the source and keep it from spreading. However, as the current outbreak of mumps in the Midwest demonstrates, a sick person can board a plane and spread a contagious disease to people hundreds or thousands of miles away.
“South Carolina is not considered a high-priority area of arrival of the (avian flu) virus,” Shipes said.
“That’s not to say it couldn’t arrive here.”
Reach Lamb at (803) 771-8454.
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Originally Posted by Glenn
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