for practical purposes it cannot be diagnosed solely on clinical features or microscopy.
Why similar infections produce vastly different outcomes in different subjects is one of malaria’s central, unsolved mysteries. Even among children with identical parasitemias, one child may be moribund with coma or severe anemia, while another is attending school or playing without apparent illness. One consequence of malaria’s often uneventful course in endemic areas is a relative nonchalance on the part of patients, parents, and health care workers toward the disease.
Some diseases like malaria are so common it’s almost like information over-load. It’s malaria, okay. Malaria again, okay. Malaria again. Once in medical school we had a visiting pathologist—I forgot what country he came from—and he said: I went to the mortuary yesterday and I was doing post mortems, and all the spleens which were being passed off as normal are malaria spleens. [So he asked] why are you passing all of these spleens as normal? And the reply was: well almost everybody here has a spleen like that.
Irene Agyepong, MD, Ghana Health Service (2002)
Viewed objectively, however, malaria exacts a chilling toll of morbidity and mortality on children. Over 90 percent of all cases of life-threatening malaria occur in sub-Saharan African children (Marsh et al., 1995), and malaria causes at least 20 percent of all deaths in children under 5 years of age in Africa (UNICEF, 2002).
Although the original World Health Organization (WHO) proposed definition of “severe malaria” was based on clinical observations in Southeast Asian adults, the multisystem nature of this syndrome also is seen in life-threatening manifestations of falciparum malaria in children in Africa, and other regions (Waller et al., 1995; Marsh et al., 1995; Allen et al., 1996). Common hallmarks of severe malaria in African children are altered consciousness, convulsions, hypoglycemia, acidosis, and anemia. The next sections will review these complications in further detail.
Anemia is a consistent marker of severe malaria in children as well as adults. Severe malarial anemia is defined as a hemoglobin concentration less than or equal to 5 g/dL in a patient with P. falciparum malaria. Until recently, overt destruction of parasitized RBCs and splenic filtration were