Studies to assess the potential causal prophylactic value of chlorguanide, pyrimethamine, and primaquine against a strain of chloroquine-resistant P. falciparum, the Thailand (JHK) strain, indicated that daily administration of chlorguanide, weekly administration of pyrimethamine, or weekly administration of primaquine may prove far from uniformly effective.
Present address: Departments of Medicine (Simpson Memorial Institute) and Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan.