The fortune that once belonged to a man who ran from germs and disease is now helping to fight them. The not-for-profit Howard Hughes Medical Institute (HHMI) is one of the nation's largest private medical research organizations. Unlike most such organizations, HHMI directly employs the researchers it funds (through a multibillion-dollar endowment) and provides needed equipment and facilities. Its staff of some 330 "investigators," as the institute calls them, includes more than a dozen Nobel Prize winners. The organization concentrates primarily on such biomedical areas as cell biology, genetics, immunology, neuroscience, and structural biology. HHMI also supports science education through a grant program.