later became an instructor in the department of com-
parative pathology and tropical medicine and an asso-
ciate professor in the Harvard Medical School of Public
Health. In July 1954 he was appointed Richard Pear-
son Strong Professor of Tropical Public Health and
head of the department at the Harvard School of Public
Health. From 1966 to 1981 he was director of Har-
vard’s Center for the Prevention of Infectious Diseases.
He contributed a great deal of research on the
helminthes parasites of humans, particular on the
nematode Trichirella spiralis and schistosome trema-
todes, which cause schistosomiasis. He isolated the
viruses of varicella and herpes zoster, showing that one
caused both diseases. In 1955 he also isolated a virus
that causes cytomegalic inclusion disease in infants.
Together with J. F. Enders and F. C. ROBBINS, he was
awarded the 1954 Nobel Prize in physiology or
medicine for work in growing polio viruses in cultures
of different tissues.
West Nile disease or fever A mosquito-borne dis-
ease that can cause encephalitis, or inflammation of the
brain, and caused by a flavivirus. West Nile fever is a
disease that has occurred before in Egypt, Asia, Israel,
South Africa, and parts of Europe, but it had never
before been found in the Western Hemisphere until
recently, appearing in America in 1999. In 2003, West
Nile virus had killed 223 people in the United States,
and there were 9,122 confirmed human cases of the
disease worldwide. Closely related to the St. Louis
encephalitis.
Whipple, George Hoyt (1878–1976) American
Pathologist George Hoyt Whipple was born on
August 28, 1878, in Ashland, New Hampshire, to Dr.
Ashley Cooper Whipple and Frances Hoyt. Whipple
was educated at Phillips Academy in Andover and
received a B.A. at Yale University in 1900. He then
completed course work at Johns Hopkins University
and received his M.D. degree in 1905, when he was
appointed assistant in pathology at the Johns Hopkins
Medical School. In 1914 he was appointed professor
of research medicine at the University of California
Medical School and was named director of the Hooper
Foundation for Medical Research at that university,
serving as dean of the medical school during the years
1920 and 1921. In 1921 he was appointed professor
of pathology and dean of the School of Medicine and
Dentistry at the University of Rochester and became
the founding dean of the university’s School of
Medicine (1921–53) and chair of the pathology
department.
Whipple’s main researches were concerned with
anemia and the physiology and pathology of the liver.
In 1908 he began a study of bile pigments that led to
his interest in the body’s manufacture of the oxygen-
carrying hemoglobin, an important element in the pro-
duction of bile pigments. His studies dealt with the
effect of foods on the regeneration of blood cells and
hemoglobin in 1918. Between 1923 and 1925, his
experiments in artificial anemia were instrumental in
determining that iron is the most potent inorganic fac-
tor in the formation of red blood cells.
For his work on liver research and treatment of
anemia, he was awarded, together with GEORGE R.
MINOTand WILLIAM P. MURPHY, the Nobel Prize in
physiology or medicine in 1934. Whipple published
many scientific papers in physiological journals.
He died on February 2, 1976, in Rochester, New
York. His birthplace home on Pleasant Street in Ash-
land was listed on the National Register in 1978.wild type The normal form, genotype, or phenotype
of an organism found or first seen in nature. It can
refer to the particular whole organism or to a particu-
lar mutation. It is the most frequently encountered
genotype in natural breeding populations.Wilson’s disease An inherited condition in which
copper fails to be excreted in the bile. Copper accumu-
lates progressively in the liver, brain, kidney, and red
blood cells. As the amount of copper accumulates,
hemolytic anemia, chronic liver disease, and a neuro-
logical syndrome develop.
See alsoCHELATION THERAPY.winterbottom’s sign Swelling of the posterior cervi-
cal lymph nodes at the base of the skull that is symp-
tomatic of having African trypanosomiasis (African
sleeping sickness). Caused by a parasite and transmit-
ted by the bite of the tsetse fly. West African trypanoso-348 West Nile disease or fever