MEDIUM CITY, NJ – Huge herds of hungry birds comb the sands of Delaware Bay for the tiny greenish eggs that are surrounded each spring by an army of horseshoe crabs.
It is a miracle of ecology as shorebird migration from South America to the Arctic period is a critical point for their survival at this mass cancer spawning season. It is also one of the world's hotspots for bird flu – a gold digger for scientists looking for signs of influenza to better protect people.
"We might like to predict what the next pandemic would be," said influenza pioneer Robert Webster of St. Jude Children's Research Hospital.
These modest beaches turn into a mixed pit for influenza between mid-May and early June. Thousands of waders and gulls crowd together and swap viruses. The researchers cautiously walk around the nest crabs to collect the evidence – potentially flu-infected bird droppings.
"We trained our eyes, that's for sure," said St. Jude researcher Pamela McKenzie as she leaned over damp sand last month looking for the freshest samples to go down for later testing ,
Not some splat will do. Too dry and tests may not be able to detect the virus. Too big, and it's probably not of the species that carries the flu here, the calico-patterned reddish stonecutter.
Why test birds? "This is where all the flu viruses come from," says Richard Webby, director of St. Jude's Center for Excellence in Influenza Research and Surveillance, a program funded by the National Institutes of Health.
Waterfowl, including wild ducks and migratory birds (19659004) Whether it's the typical winter misery or a pandemic, every disease affecting humans "started somewhere along the pedigree in the water reservoirs," said Webby.
Usually wild birds do not get sick, just act with flu viruses that they carry in the gut. But from time to time wild birds also kill domesticated chickens and turkeys and threaten pigs or even humans.
St. Jude's annual study in Delaware Bay provides insight into lesser-known efforts around the world – including the study of ducks in China and Canada and living poultry markets in Bangladesh – to monitor how bird flu circulates and changes information that determines which vaccines  And nowhere else in the world have scientists found so many shorebirds that carry a variety of influenza viruses than when red knots, reddish stone forests, and other species make their stopover in this bay between New Jersey and Delaware.
Bird flu is not easily transmitted to humans, said McKenzie, who does not even wear gloves while she spits on a beach before the tide returns.
Still, "It's amazing how the virus can change so quickly which genes they inherit," added McKenzie, who oversees the global bird flu monitoring of St. Jude.
The US is currently storing vaccines against distressing tribes  "It just has to happen once," Webby said. "The right virus comes and gets into the right population, which happens to fly over the right turkey farm, which happens at the right time of year, where the right farmer picks up the wrong bird – and we have problems."
Webster, now an emeritus virologist in St. Jude, established the link between avian and human influenza decades ago when he spotted some seabirds in Australia carrying antibodies against the strain that caused the 1957 pandemic , His ongoing hunt for bird flu led him to Delaware Bay in 1985.
Today scientists know that two different types of flu simultaneously infect a single animal – a pig, for example, captures a chicken and a human bacterium – genes can mix to produce a completely new virus.
But concern for avian influenza as a threat to poultry farms and humans has grown, since a variety called H5N1 in Hong Kong in the late 1990s poultry markets. Cousins of this virus have cropped up, as well as another flu called H7N9, which has infected more than 1,500 people in China through close contact with infected chickens since 2013.
These are very different viruses than what St. Jude finds in passing waders at Delaware Bay, Webby said. For some reason, viruses carried by Asian and European birds rarely come to America, he said, but it's important to look – and to understand the normal ebb and flow of different strains, so it's more obvious when something new appears ,  Research is "a way to be a little ahead of the virus," said Marcia DeGrace of the NIH's National Institute of Allergy and Infectious Diseases. "Understanding how the virus can change and how quickly it can change in a short time is crucial for us to take countermeasures such as vaccines."
Why flu breaks out during the stopover at Delaware Bay 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 has just arrived here. "They are here to do work," said Alinde Fojtik of the University of Georgia's Southeastern Cooperative Wildlife Disease Study , a longtime flu researcher, volunteered their holidays this year to count and label shorebirds
So the birds can sleep uninterruptedly, only scientists and conservation workers are allowed to carefully catch and count on their favorite beaches, testing their overall health and tag them for the persecution as the migration progresses.
Finding the right place is a trick for the fluseeker. St. Jude researcher Patrick Seiler takes off his binoculars: No, mostly seagulls on a beach. Down the road, he spies a better target, a lot of reddish stonecutter with their distinctive black, white and brown plumage.
The troubled birds flee as the team approaches. Each drop is thawed on a cotton swab, placed in a small vial of preservative and stored in a cool box.
The team carried more than 600 samples back to St. Jude's Labs in Memphis, Tennessee, where researchers begin the months-long process to test how many excrement influenza and what type. The virus library is being used for used further experiments to test how well strains spread, said DeGrace of NIH.
"I would like to see the sequence of viruses we find in Delaware Bay this year." Oh, oh, that's the guy that's coming. "We're not there yet," warned Webby. "This is our ultimate goal of being able to say, 'oh, oh, we have to worry about that.'"
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