Changes in malaria associated morbidity in children using insecticide treated mosquito nets in the Bagamoyo district of coastal Tanzania.

A community based malaria control intervention using insecticide treated mosquito nets (IMN) has been implemented and tested in 13 villages of the Yombo Division, Bagamoyo District in the Coastal Region, Tanzania, an area holoendemic for P. falciparum malaria. Following extensive sociological research into local perceptions of malaria, the programme was implemented. It wa decided by consensus that village mosquito net committees would be the appropriate local level implementors. These were formed and provided with IMN's which were sold to villagers at subsidised cost. The income was invested for use by the committees for sustaining the activity. Use patterns were determined and high coverages were obtained among the community, particularly after promotions e.g. plays, school meetings etc. Malaria morbidity was measured among children 6-40 months of age in 7 index villages prior to the intervention in 1992 and in a comparison study between 3 villages using nets and 4 villages not using nets in 1993. Examination of the 7 cohorts of children was done from June to October each year covering the period of most severe transmission. The children using nets showed marked improvement in several malariometric indices. Following an initial clearance of parasitaemia with sulphadoxine/pyrimethamine, when compared with unprotected children, those with nets were slower to become re-infected (Relative Risk 0.45), had lower parasitaemias and showed marked improvement in anaemia (RR 0.47). Use of IMN's produced a 54% reduction in the prevalence of anaemia among young children. Attempts are being made to ensure that the programme is locally sustained.

Anaemia and Plasmodium falciparum infections among young children in an holoendemic area, Bagamoyo, Tanzania.

Although the aetiology of anaemia in tropical areas is multifactorial, Plasmodium falciparum malaria is commonly associated with anaemia in children living in holoendemic malaria areas. Such an association was examined in a population based study of 338 children 6 to 40 months of age living in the Bagamoyo area of Tanzania. Stepwise regression analysis showed that fever and parasitaemia were effective in predicting anaemia and that the anaemic condition was age dependent. The majority of the children were iron deficient, followed by normochromic macrocytic anaemias. There was strong evidence in this age group that the anaemia was associated with malaria and not geohelminth infection. The importance of malaria and anaemia as a cause of childhood morbidity in Africa is discussed. This condition has taken on new significance with the realization that blood transfusions commonly used to treat severe anaemia are a major vehicle for Human Immunodeficiency Virus (HIV) transmission.

PIP: Anemia is an important cause of morbidity and probably mortality in patients with acute Plasmodium falciparum infection. The authors investigated the association between P. falciparum malaria and anemia in children living in holoendemic malaria areas in their population-based study of 338 children aged 6-40 months living in the Bagamoyo area of Tanzania. The study was conducted from late May to October 1992 when malaria transmission is high in coastal Tanzania. The children were selected at random from seven villages in the study area and not on the basis of a history of illness, suspected malaria, or any other health reason. All children were examined by a physician and detailed medical histories were taken. At enrollment, 2.5% of the children were severely anemic and 74.1% were anemic. With treatment and active surveillance, the incidence of severe anemia dropped to 1.4% and anemia to 69.5%. Stepwise regression analysis found fever and parasitemia to effectively predict anemia and that the anemic condition was age dependent. The majority of children infected with P. falciparum were iron deficient, followed by normochromic macrocytic anemias, with strong evidence that the anemia was associated with malaria and not geohelminth infection. The authors consider the importance of malaria and anemia as a cause of childhood morbidity in Africa and comment on the realization that blood transfusions commonly used to treat severe anemia are a major vehicle for HIV transmission.