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Huge flocks of hungry birds scour the sands of Delaware Bay for the tiny greenish eggs that an army of horseshoe crabs lay each spring
C & # 39; is a marvel of ecology as shorebirds migrate from South America to the Arctic. their survival at this mbad crab spawn. It's also one of the hotspots of bird flu in the world – a windfall for scientists looking for clues about how the flu is changing to better protect people
"Finally, we would like to be able to predict what will be next. "Robert Webster, Influenza Pioneer, St. Jude Children's Research Hospital
These humble Middle Town beaches turn into a mix of flu between mid-May and In early June, as thousands of shorebirds and gulls gather viruses, researchers cautiously move around breeding crabs to gather evidence – bird droppings potentially infected with the flu.
"We've trained our eyes for this, that's for sure," says St. Jude researcher Pamela McKenzie last month looking for the freshest samples to go on the ice for testing later.
P No matter what splat will do the business. Too dry, and tests may not be able to detect viruses. Too big, and it is probably not the case that bears the most flu here, reddish roulette calico pattern.
Why test birds? "That's where all the flu viruses come from," said Richard Webby, director of St. Jude's Center for Excellence in Influenza Research and Surveillance, a program funded by the Canadian Institutes of Health. National Institutes of Health
.
Whether it's typical winter misery or a pandemic, every strain that infects humans "began somewhere along the family tree in the waterfowl tanks," said Webby. the birds do not get sick, they simply exchange flu viruses that they carry in the intestines. But strains of wild birds can threaten domestic chickens and turkeys and, from time to time, they jump to pigs or even people.
Jude's annual study at Delaware Bay provides insight into little-known efforts around the world – including testing of migrating ducks in China and Canada and live poultry markets in Bangladesh – to track circulation and changes in bird flu. which vaccines for animals and humans.
And nowhere else in the world have scientists found as many shorebirds carrying various influenza strains as when red knots, peat bogs and other species make a migratory stopover in this bay between New Jersey and New Jersey. Delaware
Most cases of bird flu are not easily transmitted to the population, says McKenzie, who does not even wear gloves when she fails along a beach before Tide Removes
Still, "It's amazing how the virus can change so quickly, what genes they inherit," added McKenzie, who oversees global surveillance of St. Jude's bird flu
. stocks just-in-case vaccines against worrying strains.
"It must only happen once," said Webby. "The right virus arrives and enters the right population that flies over the good turkey farm that comes at the right time of year when the good farmer picks up the wrong bird – and we have problems." [19659002] Webster, now a virologist emeritus at St. Jude, made the connection between birds and human flu decades ago when he found seabirds in Australia carrying antibodies against the strain that caused the pandemic from 1957. In 1985, his pursuit of avian flu led him to Delaware Bay
. Today, scientists know that if two types of flu infect a single animal at the same time, say that a pig catches both a chicken strain and a human. But the fear of bird flu as a threat to poultry farms and humans has increased since a strain named H5N1 spread directly to people in the late 1990s in the crowded world of Hong Kong . live poultry markets. Cousins of this virus have appeared, along with another influenza named H7N9 that since 2013 has infected more than 1,500 people in China through close contact with infected chickens.
These are viruses very different from what St. Jude finds in Delaware Bay shorebirds, Webby said. For some reason, viruses carried by Asian and European birds rarely arrive in America, he says, but it's important to look at – and understand the normal ebb and flow of different strains, more obviously. 19659002] Research is "a way to stay a little ahead of the virus," said Marciela DeGrace of the NIH's National Institute of Allergic and Infectious Diseases. "Understanding how this virus can change and how much it can change quickly will become critical for us to make countermeasures like vaccines."
Shorebirds feast on horseshoe crab eggs on Delaware Bay beaches in Cape May County
Why the flu bursts during the stopover of Delaware Bay remains a mystery. But the longest travelers arrive wasted and have to double their weight in two weeks
"You can hold a bird and say:" This bird just happened to arrive. "They are there to make their work, "said Alinde Fojtik, of the Southeastern Cooperative Wildlife Disease Study at the University of Georgia, a long-time researcher who volunteered her vacation to help count and tag shorebirds
. scientists and conservation workers are permitted on their favorite beaches, catch and count them carefully, test their general health and mark them to follow the migration.
For flu hunters, finding the right place is St. Julian researcher Patrick Seiler takes out binoculars: No, especially seagulls on a beach, on the road he sees a better target, a crowd of blushing stones with black, white plumage and distinctive brown.
Nervous birds take flight as the team approaches. Each drop is brought on a cotton swab, placed in a small vial of preservative and stored in a cooler.
The team transported more than 600 samples to St. Jude Laboratories in Memphis, Tennessee, where researchers begin the month. process to test how many droppings carry the flu and what type. The viral library is used for other experiments to test the spread of strains, says DeGrace of the NIH.
"I'd love to be able to watch the virus sequence that we find in Delaware Bay this year:" Oh, oh, that's the guy who's coming. We are not there yet, "warned Webby. "It's our ultimate goal, to be able to say," Oh, oh, here's something we need to worry about. "
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