The intensity of malaria transmission by its anopheline vectors
varies enormously , and this affects most quantitative aspects
of malaria epidemiology . A commonly used index of malaria
transmission intensity is the Plasmodium falciparum parasite
rate (PfPR), the proportion of the population found to carry
asexual blood-stage parasites. In mathematical models, PfPR is
related to the entomological inoculation rate (EIR), the number
of bites on a person by sporozoite positive vectors, at the
steady state [3,4]. The notion of a steady state has limited
application for PfPR, however, because PfPR follows a well-
established pattern as a function of age and transmission
intensity; PfPR rises during infancy and early childhood [5,6],
settles to a plateau in older children, and declines in
adolescents and adults as malaria immunity develops [7-10]. This
pattern has been known for decades [11,12], but there are no
established standards for reporting PfPR, so thousands of
studies have reported crude PfPR, without strat