Quinine and chloroquine affect malarial parasites only at life stages when the parasites are forming hematin-pigment (hemozoin) as a byproduct of hemoglobin degradation.
It was horrible, a writer said, the 400 miserable, helpless, emaciated specimens of humanity, subjected for months to the malarial atmosphere of the river bottom.
Among protozoan endoparasites, such as the malarial parasites and trypanosomes, infective stages in the hosts blood are transported to new hosts by biting-insects, or vectors.