Studies on the epidemiology of malaria in New Guinea

Summing up the above data we can say that there is as intense transmission in Maprik as can be found in holoendemic areas of Africa, such as the Sigi Valley (Davidson and Draper, 1953) and that this results in a clinical picture differing from that in Africa only in the parasite ratio. We feel that Metselaar, (1956a, 1957), is correct in ascribing this to the absence of the sickle-cell gene from New Guinea indigenes, but disagree that the WHO (1951) classification of endemicity cannot be applied here. There is no doubt that transmission is much more intense in Maprik even than in the Nimboran Valley and the lower inoculation rate and higher adult spleen rates found there are accounted for by this. We have attempted to show that there is a grading in New Guinea of the intensity of malaria transmission so that a single survey conducted at random in any part of the country may show anything from the absence of malaria to true holoendemicity. In the next part of these studies we will give the entomological evidence for these statements, and in later parts will make a comparison with the situation in an area of unstable seasonal malaria, i.e. Minj. References in the text will be listed at the conclusion of Part III of this series.