The examination of a representative sample of the population for splenic enlargement is a method that has been widely used in estimating the incidence, and to some extent the severity, of malaria in a community. Such examinations are usually made on children. Palpation for enlarged spleen, if it will give a reasonably accurate idea of the extent of infection, is a much easier and more rapid method of malariometry than the collection and examination of specimens of the peripheral blood. Attention has been drawn recently, however, to the influence of race in determining whether or not the spleen will present rather constant enlargement in subacute and chronic malaria.
Clark (1), in a report of a study of spleen and malaria parasite rates in Haitian negroes, says that not more than one-eighth of the cases of malaria in adults, proved by blood examination, would have been found if reliance had been placed solely on splenic tumor, and in children only about half of the cases would have been discovered.