He had meningococcemia, a relatively rare and very dangerous bacterial infection that most often strikes children under four. Meningococcemia develops when the same bacteria that cause meningitis get into the blood and cause widespread clotting.
Many children die as a result, and others survive with amputated limbs.
Jefferson's grandfather, a pediatrician, had never seen a child survive this disease in 40 years of practice. At the hospital near the family's home in Fairfield, an emergency room physician suspected meningococcemia and arranged for Jefferson to be transported to Children's Hospital Oakland by helicopter. His parents followed by car. He was in the fulminating stage of the disease, and blood clotting had turned his arms and legs purple. When Jefferson's parents arrived, they found him in the ICU, with a medical team around him and numerous IV lines running into his body.