Super Spreaders
“Fire!”
A baritone retort accompanies a spray of tawny sand as a large cannon net stretches wide. Small shorebirds with white bellies and mottled orange and black feathers try to flee, but the net is faster: It settles and traps a flock of Ruddy Turnstones underneath. A ragtag crew leaps up and dashes to the indignant birds. With an efficiency and precision that Henry Ford would have envied, the team gets to work.
Migratory birds pack the New Jersey Shore for the same all-you-can-eat seafood buffets and fresh ocean breezes that attract humans. Only their journey is far more epic. Every year, tens of thousands of Red Knots and Ruddy Turnstones winter as far away as Tierra del Fuego, off the southern tip of South America, and travel hundreds or thousands of miles to Delaware Bay. Dunlins, Semipalmated Sandpipers, Sanderlings, Herring Gulls, and Laughing Gulls join them there. As humans feast on popcorn shrimp and fried clams, the birds pursue horseshoe crab eggs with a single-minded obsession. The bay’s bountiful supply can double the weight of Red Knots—stripped of their energy by a week or more of flight—in just a few weeks.
Shorebirds, however, pick up more than fat reserves during their stay. The mingling of so many birds, packed beak to tail, along small stretches of sand creates the perfect breeding ground for disease. When they arrive from their winter habitat to Delaware Bay, only low percentages of turnstones, for example, have antibodies to influenza. By the time they restart their journey to Arctic breeding grounds, tests can show roughly 60 percent have been exposed.
All human influenza pandemics begin with a strain of virus that evolved in wild bird populations. The virus doesn’t appear to harm the wild birds, but it can occasionally spread to other animals and jump to people. When that happens, the outcome can be mild—or devastating. In 1918 influenza created the deadliest outbreak in recent history, killing upward of 50 million people (2 out of every 100 human beings alive at the time).
That’s why a team of scientists gathered on the
