Household-based malaria control in a highly endemic area of Africa (Tanzania): determinants of transmission and disease and indicators for monitoring - Kilombero Malaria Project

Abstract

The Kilombero Malaria Project (KMP) attempts to define operationally useful indicators of levels of transmission and disease and health system relevant monitoring indicators to evaluate the impact of disease control at the community or health facility level. The KMP is a longitudinal community based study (N = 1024) in rural Southern Tanzania, investigating risk factors for malarial morbidity and developing household based malaria control strategies. Biweekly morbidity and bimonthly serological, parasitological and drug consumption surveys are carried out in all study households. Mosquito densities are measured biweekly in 50 sentinel houses by timed light traps. Determinants of transmission and indicators of exposure were not strongly aggregated within households. Subjective morbidity (recalled fever), objective morbidity (elevated body temperature and high parasitaemia) and chloroquine consumption were strongly aggregated within a few households. Nested analysis of anti-NANP40 antibody suggests that only approximately 30% of the titer variance can be explained by household clustering and that the largest proportion of antibody titer variability must be explained by non-measured behavioral determinants relating to an individual's level of exposure within a household. Indicators for evaluation and monitoring and outcome measures are described within the context of health service management to describe control measure output in terms of community effectiveness.

Evaluation of C-reactive protein and haptoglobin as malaria episode markers in an area of high transmission in Africa

“…In community studies subjective and objective measures of malarial morbidity are not always closely correlated (TEUSCHER, 1992). A CRP dependent case definition would be useful in field studies concerned primarily with the underlying biological processes of the disease, since it is likely that only a small proportion of inflammatory responses caused by malaria parasites is detectable either as measurable fever or by fever recall.…”

“…A CRP dependent case definition would be useful in field studies concerned primarily with the underlying biological processes of the disease, since it is likely that only a small proportion of inflammatory responses caused by malaria parasites is detectable either as measurable fever or by fever recall. Such a definition is less appropriate in field studies which are focused on perceived illness at the community level, when identification of episodes by fever recall can be used (TEUSCHER, 1992).…”

“…The geographic, demographic and health aspects of the study area have been described in detail by TANNER et al (1987TANNER et al ( , 1991. Two neighbouring villages lying in the Kilombero river plain are the subject of research activities of the Kilombero Malaria Project* (KILOMBERO MALARIA PROJECT, 1992;SMITH et al, 1993;TEUSCHER, 1992). The area is highly endemic for P. falciparum malaria.…”

“…Community controls, used in the estimation of the sensitivity and specificity of case definitions, were afebrile children under 6 years of age sampled during household surveys between June 1989 and November 1991, as described elsewhere (SMITH et al, 1993;TEUSCHER, 1992).…”

Rapid assessment of malaria risk using entomological techniques: taking an epidemiological snapshot

“…Use of anti-mosquito measures such as bednets, mosquito coils, insecticides and repellents -all of which may be seasonally influenced (Charlwood et al 1995b) -should be recorded. Simple questionnaires can also provide useful indicators on such things as anti-malarial drug usage, where people B perceive mosquito populations to be high and of the presence of standing water (Teuscher 1992;Minja et al 2001). In addition, recruitment of local expertise into the RA should excite local interest and provide opportunities for health education.…”