It was just an e-mail about a single case of illness, but a gut instinct developed through years of disease detective work made Dr. Marion Kainer sense a bigger danger. Kainer, the director of health care-associated infections for the Tennessee Department of Health, started investigating the day she got that e-mail and hasn't stopped since. She camped out in her office for three weeks, leading a team of state workers as they traced the source of what would become a national outbreak of fungal meningitis.