Awash Teklehaimanot

Weather-based prediction of Plasmodium falciparum malaria in epidemic-prone regions of Ethiopia I. Patterns of lagged weather effects reflect biological mechanisms

BackgroundMalaria epidemics due to Plasmodium falciparum are reported frequently in the East African highlands with high case fatality rates. There have been formal attempts to predict epidemics by the use of climatic variables that are predictors of transmission potential. However, little consensus has emerged about the relative importance and predictive value of different factors. Understanding the reasons for variation is crucial to determining specific and important indicators for epidemic prediction. The impact of temperature on the duration of a mosquitos life cycle and the sporogonic phase of the parasite could explain the inconsistent findings.MethodsDaily average number of cases was modeled using a robust Poisson regression with rainfall, minimum temperature and maximum temperatures as explanatory variables in a polynomial distributed lag model in 10 districts of Ethiopia. To improve reliability and generalizability within similar climatic conditions, we grouped the districts into two climatic zones, hot and cold.ResultsIn cold districts, rainfall was associated with a delayed increase in malaria cases, while the association in the hot districts occurred at relatively shorter lags. In cold districts, minimum temperature was associated with malaria cases with a delayed effect. In hot districts, the effect of minimum temperature was non-significant at most lags, and much of its contribution was relatively immediate.ConclusionsThe interaction between climatic factors and their biological influence on mosquito and parasite life cycle is a key factor in the association between weather and malaria. These factors should be considered in the development of malaria early warning system.

The African Millennium Villages

We describe the concept, strategy, and initial results of the Millennium Villages Project and implications regarding sustainability and scalability. Our underlying hypothesis is that the interacting crises of agriculture, health, and infrastructure in rural Africa can be overcome through targeted public-sector investments to raise rural productivity and, thereby, to increased private-sector saving and investments. This is carried out by empowering impoverished communities with science-based interventions. Seventy-eight Millennium Villages have been initiated in 12 sites in 10 African countries, each representing a major agroecological zone. In early results, the research villages in Kenya, Ethiopia, and Malawi have reduced malaria prevalence, met caloric requirements, generated crop surpluses, enabled school feeding programs, and provided cash earnings for farm families.

Scaling-up coverage with insecticide-treated nets against malaria in Africa: who should pay?

Insecticide-treated nets (ITNs) have been shown to reduce the burden of malaria in African villages by providing personal protection and, if coverage of a community is comprehensive, by reducing the infective mosquito population. We do not accept the view that scaling-up this method should be by making villagers pay for nets and insecticide, with subsidies limited so as not to discourage the private sector. We consider that ITNs should be viewed as a public good, like vaccines, and should be provided via the public sector with generous assistance from donors. Our experience is that teams distributing free ITNs, replacing them after about 4 years when they are torn and retreating them annually, have high productivity and provide more comprehensive and equitable coverage than has been reported for marketing systems. Very few of the free nets are misused or sold. The estimated cost would be an annual expenditure of about US

Malaria control needs mass distribution of insecticidal bednets

295 million to provide for all of rural tropical Africa where most of the worlds malaria exists. This expenditure is affordable by the world community as a whole, but not by its poorest members. Recently, funding of this order of magnitude has been committed by donor agencies for malaria control.

Estimating the needs for artesunate-based combination therapy for malaria case-management in Africa.

Long-lasting insecticidal bednets (LLINs) are one of the major ways to control malaria and they are widely accepted worldwide by communities in areas affected by malaria. One LLIN costs about US

Weather-based prediction of Plasmodium falciparum malaria in epidemic-prone regions of Ethiopia II. Weather-based prediction systems perform comparably to early detection systems in identifying times for interventions

5 to manufacture and is effective for about 5 years. They have two kinds of protective effects-one for the people directly under the nets and one for the community at large. The second effect is important but often ignored. By achieving high community coverage to ensure a substantial community protection malaria-control efforts can be more powerful than when only individual protection is attempted. The direct effect of LLINs is to protect the people sleeping under them and it operates in three ways. First the insecticide kills some of the Anopheles mosquitoes after a few minutes. Second the LLIN repels a proportion of the mosquitoes after contact. Third the net acts as a mechanical barrier to biting. The mechanical barrier provides half or less of the protection which is why bednets without insecticide are less effective than treated ones. (excerpt)

Estimated global resources needed to attain international malaria control goals

Because of inadequacies in national health information systems, the volumes of drugs required to support an effective policy transition toward artesunate-based combination therapy (ACT) are unknown for most African countries. A series of national surveys and population projections have been used to estimate the age-structured fever burden among 41 malaria endemic countries in Africa. Under present fever-management guidelines, commodity costs and internationally agreed coverage targets, the financial resources to meet the needs of ACT in most African countries are huge. Between US

The effect of an integrated multisector model for achieving the Millennium Development Goals and improving child survival in rural sub-Saharan Africa: a non-randomised controlled assessment

1.6 billion and US

Rapid urban malaria appraisal (RUMA) in sub-Saharan Africa

3.4 billion per annum must be found to give Africa the chance to consider a drug policy based on ACT. Substantial reductions in these costs would be achieved through more effective targeting of resources--only 20% of drugs would be required to manage fevers among the most at-risk pediatric patient populations. Better diagnostics would also be an important consideration for a new ACT policy in Africa.

Human resource development for a community-based health extension program: a case study from Ethiopia

BackgroundTimely and accurate information about the onset of malaria epidemics is essential for effective control activities in epidemic-prone regions. Early warning methods that provide earlier alerts (usually by the use of weather variables) may permit control measures to interrupt transmission earlier in the epidemic, perhaps at the expense of some level of accuracy.MethodsExpected case numbers were modeled using a Poisson regression with lagged weather factors in a 4th-degree polynomial distributed lag model. For each week, the numbers of malaria cases were predicted using coefficients obtained using all years except that for which the prediction was being made. The effectiveness of alerts generated by the prediction system was compared against that of alerts based on observed cases. The usefulness of the prediction system was evaluated in cold and hot districts.ResultsThe system predicts the overall pattern of cases well, yet underestimates the height of the largest peaks. Relative to alerts triggered by observed cases, the alerts triggered by the predicted number of cases performed slightly worse, within 5% of the detection system. The prediction-based alerts were able to prevent 10–25% more cases at a given sensitivity in cold districts than in hot ones.ConclusionsThe prediction of malaria cases using lagged weather performed well in identifying periods of increased malaria cases. Weather-derived predictions identified epidemics with reasonable accuracy and better timeliness than early detection systems; therefore, the prediction of malarial epidemics using weather is a plausible alternative to early detection systems.