Salk inclined his head toward the other, younger children. “Hope they’re not afraid of them,” he said in a whisper. Bill smiled, and Salk looked inquiringly at the needles.
“OK if we proceed?” Salk asked.
The boy nodded, a little surprised to have been asked. Salk took up the syringe, slid the needle into a vein and withdrew a vial of blood. He regarded the vial closely for a moment, then labeled it carefully.
“Thank you,” he said, “for going first.”
Bill shrugged. “I have two nephews. I don’t want them to get what I had.”
Over the next two hours, the 39 other Watson volunteers came forward. After all of the blood samples had been drawn, Salk offered his thanks once more, packed up his tools and drove back to Pittsburgh.
Half past seven in the morning was the time Elsie Ward usually set aside to feed her babies—or that was what she liked to call them. In truth, they were monkey cells growing
in test tubes, and Ward cared for them dearly. In her small corner of Jonas Salk’s lab, she protected them, fretted over them, kept them nourished with warm helpings of nutrient.
It would fall to Ward to test whether the polio vaccine had worked in the Watson Home children. First, a test tube was seeded with healthy monkey cells. Serum from the blood of Watson children who’d been vaccinated that summer was then mixed with poliovirus and dripped into the test tubes. If antibodies were present in the children’s blood in sufficient amount in response to the vaccine, the viruses would be disabled and the cells would survive. But if the antibodies were too weak, or too few, the viruses would be free to bloom, and the cells would die.