1. Infectious Diseases Department, Naval Medical Research Institute, Bethesda, MD 20814-5055.
2. Department of Immunology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
3. Kenya Medical Research Institute, U.S. Army Medical Research Unit-Kenya, Nairobi, Kenya.
4. Cornell University Medical College, New York, NY 10021.
5. Biomedical Research Institute, Rockville, MD 20852.
6. Department of Entomology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
7. Kenya Medical Research Institute, Nairobi, Kenya.