text: A sizeable army of scientists and technicians labored at the Communicable Disease Center in Atlanta and the National Institutes of Health at Bethesda, Maryland, to develop an immunizing agent effective against FHF. They made no progress. Technicians could not grow the virus in cell cultures—a prerequisite to creating a vaccine. The CDC began a crash program to develop a cell-culture system for the FHF virus. The small quantity of virus available from cats that had died of FHF was purified and tested as an immunizing agent. It failed to elicit a protective immune response in cats. The investigators surmised that the failure was a due to the FHF virus possessing three classes of envelope proteins—one derived from FIV, one from FeLV, and a third from Ebola.
  
  Darth Vader, Leland Meredith's companion animal, died suddenly of FHF. The autistic boy fell into a deep depression and became totally uncommunicative. After trying their best to cope, Mr. and Mrs. Meredith admitted defeat and had Leland institutionalized.