(1973) n°3 - Royal Academy for Overseas Sciences

— 514 —
fed, but only three became infected. As a donor, I was practically
useless, so 7 mis of my blood were inoculated into Dr.
L a in s o n and I received curative treatment. This attempt to
obtain infection was little better and L a in s o n ’s blood was
passed to Dr. B r a y , another member of my department, with
equally poor results. My Egyptian student Dr. A w a d followed
in succession but he also producted no suitable gametocytes.
W e had now nearly exhausted the supply of volunteers when
the Scottish biochemist Dr. James W il l ia m s o n at last developed
an excellent gametocytaemia after the parasite had been
passed through mosquitoes. Mosquitoes were fed on him and
77 % became well infected. Sporozoites appeared in the salivary
glands and nearly a thousand infected mosquitoes were allowed
to bite William C o o p e r , my chief technician, who had
volunteered for the final experiment involving the liver biopsy.
The timing of the biopsy had to be carefully judged and we
decided that 9 days should represent the maturation period. The
operation was performed satisfactorily, sections were cut and
beautiful, most characteristic exoerythrocytic schizonts were demonstrated
( G a r n h a m et al. 1955). C o o p e r was of course
still in hospital, and actually had a hypostatic pneumonia. He
insisted on having a microscope brought to his bed and examined
the material. A little later, he painted a remarkable series
of pictures of the schizonts in his own liver.
The problem of P. malariae remained unsolved. I had shown
in 1951 that the quartan parasite (P. inut) of Asian macaques
had a prepatent period lasting 12 days. By this time Bray by
substituting chimpanzees for men, had succeeded in I960 in finding
the early stages o f P. malariae in their livers. He had taken
my figure of 12 days as the guide line for his experiments —
another misleading clue.
It seemed important to complete the study of the life cycle
of P. malariae in its later stages in the liver, and when Romanian
workers described a Moldavian strain (VS) of the quartan
parasite, which gave rise to heavy infections in mosquitoes,
we at once realised that here was our opportunity. W e planned
accordingly with P.C. Sh u t e (our collaborator in the P. vivax
and P. falciparum work) that he should go to Bucarest and
infect large batches of mosquitoes on patients who had been