Adrianus Pijper, pathologist and microbiologist, younger brother of
Cornelis Pijper*, was the son of Fredrik Pijper, professor of church history at
the University of Leiden, and his wife Maria Petronella, born van Wijk. He
received his secondary education at the Leiden Gymnasium (1898-1904) and then
studied medicine at the University of Leiden. While a senior student during
1910-1912 he held assistantships in physiology, histology, anatomy, pathology
and bacteriology. He qualified as Doctor of Medicine (MD) in 1912 with a thesis
titled Het Coli-Vaccin (The Coli
vaccine). After qualifying he received a travelling scholarship from the
university and used it to study at the School of Tropical Medicine and Hygiene
in Hamburg, Germany, where he obtained the Diploma in Tropical Medicine in
1912. That same year, like his elder brother, he qualified as a Licentiate in Medicine and Surgery of
the Society of Apothecaries (London).
Pijper came to South Africa in 1913 and, again like his elder brother, settled in Bethal,
Mpumalanga, to practice medicine. He also continued his research in
bacteriology and pathology by equipping a private laboratory with the limited
facilities available to him in a small town. In 1920 he moved to Pretoria,
where he became a successful consulting pathologist with his own private
laboratory. He served as pathologist to the Pretoria General Hospital
(1920-1951), the Pretoria Mental Hospital (1922-1951), and the Pretoria
Municipal Health Department; as medical officer in charge of the municipal
venereal clinics of Pretoria for some years from 1922; as medical assessor for
vital statistics at the South African Census Office; as a member of the
Westfort Leprosy Committee (1925-1951) and Leprosy Advisory Board of South
Africa (1924-1939); and as the first professor of pathology and director of the
Institute of Pathology at the University of Pretoria from 1946 to his
retirement in 1951. After his retirement he continued his research with
financial and other assistance from the University of Pretoria and the Council
for Scientific and Industrial Research, until shortly before his death.
In his research Pijper focussed on an extensive range of
medical and scientific problems that arose in his work as a consulting
pathologist. He was an original thinker who insisted on the highest possible
integrity in scientific research, was very skilled in designing his own
equipment, and published his findings in over 150 scientific articles. His
research dealt mainly with the following topics: (1) The recognition of tick-bite
fever (with Dr J.M. Troup, The Lancet,
1931), a disease closely allied to South African typhus and caused by a parasitic
micro-organism (Rickettsia rickettsi var.
pijperi) that Pijper identified. His early papers on this topic included
'The aetiology of tick-bite fever' (Journal
of Tropical Medicine and Hygiene, 1930) and papers in the British Journal of Experimental Pathology (1930, 1931). (2) The
distribution of the different blood groups among the South African population,
reported in the Proceedings of the Royal
Academy of Amsterdam (1929, for the South African Dutch), the Transactions of the Royal Society of South
Africa (1930, for the Bantu), the Journal
of the Medical Association of South Africa (1932, for the San), and the South African Medical Journal (1935, for
the Khoi). (3) The diffraction method of determining the size of microscopic particles
such as red blood cells, and the construction of an instrument which applied
this method and proved useful in the diagnosis of rare blood diseases. His
experiments, which started in 1918, were recognised by the South African
Institute for Medical Research as original work of high quality and rewarded
with a donation of 100 guineas (105 pounds sterling) in 1920. Soon apparatus
constructed along the lines indicated by him were in use in hospitals and
laboratories all over the world. This work was published in various articles in
the Medical Journal of South Africa
(1918, 1919), the South African Medical
Record (1919, 1923, 1925), the South
African Journal of Science (1919), and the British Medical Journal (1929). (4) The development of a
satisfactory method for diagnosing typhoid and related fevers by means of
complement-fixation, first reported in the Journal
of the Medical Association of South Africa (1927). His method was
subsequently simplified and brought into line with those of other researchers.
(5) The introduction in South Africa of fever therapy for paresis (a psychosis
caused by syphilitic infection of the brain), described in the South African Medical Record (1926) and
later papers. (6) The first detection of the fungal disease sporotrichosis in
South Africa in his laboratory in 1925 (by his colleague Dr B.D. Pullinger) reported
in The Lancet (1927) and the study of
the fungus that caused it (e.g., Journal
of the Medical Association of South Africa, 1931); also the study of some
other fungal diseases and the discovery and description of several new
pathogenic fungi. Some of his early work in this area was reported in five
papers on 'Unusual infections' (Medical
Journal of South Africa, 1917) dealing with Thrush, Moniliasis,
Nocardiasis, Nocardia infection of the bladder, and Coccidiosis. (7) The
extension of dark-field methods in microscopy by replacing artificial light
sources by direct sunlight, which enabled him to observe the delicate flagella
of certain bacteria in the living state. His meticulous observations convinced
him that bacteria were not moved by their flagella, but by undulatory movement
of the bacterial cell itself, a view that led to much controversy.
Pijper served as a member of the South African Medical
Council from 1941 to 1948. He became a member of the South African Association
for the Advancement of Science in 1919 and served as its president in 1943. In
1920 he became a member of the South African Biological Society and later
served as its president for 1925 and 1930.
The honours and awards that Pijper received included
honorary doctoral degrees from the University of Pretoria (1943) and the
University of Cape Town (1953), the South Africa Medal (gold) of the South
African Association for the Advancement of Science (1933), the Senior Captain
Scott Memorial Medal of the South African Biological Society (1930), the
Hamilton Medal of the South African Medical Association (1924), the Silver
Medal of the South African Medical Association (1958), and the King George V
Jubilee Medal (1935). He was elected an Honorary Fellow of the Royal
Microscopical Society (1934), and a Fellow of the Royal Society of South
Africa (1934).
In 1913, in Leiden, Pijper married Nelly Margaretha Marie
Kluyver, with whom he had two sons and a daughter.
