Impregnated nets cannot fully substitute for DDT : field effectiveness of Malaria prevention in Solomon Islands

The incidence of malaria in Solomon Islands has been declining since 1992, but there is a large geographical variation between areas in the incidence level and the rate of decline. The authors used a mix of control interventions, including DDT residual house spraying and insecticide-treated mosquito nets. Data on monthly incidence and control activities performed from January 1993 to August 1999 were gathered for 41 out of the 110 malaria zones in the country. Monthly reports on the number of fevers seen at outpatient health clinics in the same zones over the same period were also extracted from the clinical health information system. The authors used multivariate random effects regression, including calendar month as an instrumental variable, to investigate the relationship between the number of malaria or fever cases and the control measures applied by month and zone, while adjusting for rainfall and proximity to water. The results showed that DDT house spraying, insecticide treatment of nets, and education about malaria were all independently associated with reduction in incident cases of malaria or fever, while larviciding with temephos was not. This was true for confirmed malaria cases even when a variable representing the passage of time was included in the models. The results show how much each method used was contributing to malaria control in Solomon Islands and how it can be used to design the most cost-effective package of interventions. The evidence suggests that impregnated bednets cannot easily replace DDT spraying without substantial increase in incidence, but impregnated nets do permit a substantial reduction in the amount of DDT spraying.Health Monitoring&Evaluation,Public Health Promotion,Climate Change,Disease Control&Prevention,Early Child and Children's Health,Health Monitoring&Evaluation,Climate Change,Malaria,Early Child and Children's Health,Health Indicators

HIV prevention costs and program scale: data from the PANCEA project in five low and middle-income countries

<p>Abstract</p> <p>Background</p> <p>Economic theory and limited empirical data suggest that costs per unit of HIV prevention program output (unit costs) will initially decrease as small programs expand. Unit costs may then reach a nadir and start to increase if expansion continues beyond the economically optimal size. Information on the relationship between scale and unit costs is critical to project the cost of global HIV prevention efforts and to allocate prevention resources efficiently.</p> <p>Methods</p> <p>The "Prevent AIDS: Network for Cost-Effectiveness Analysis" (PANCEA) project collected 2003 and 2004 cost and output data from 206 HIV prevention programs of six types in five countries. The association between scale and efficiency for each intervention type was examined for each country. Our team characterized the direction, shape, and strength of this association by fitting bivariate regression lines to scatter plots of output levels and unit costs. We chose the regression forms with the highest explanatory power (R²).</p> <p>Results</p> <p>Efficiency increased with scale, across all countries and interventions. This association varied within intervention and within country, in terms of the range in scale and efficiency, the best fitting regression form, and the slope of the regression. The fraction of variation in efficiency explained by scale ranged from 26% – 96%. Doubling in scale resulted in reductions in unit costs averaging 34.2% (ranging from 2.4% to 58.0%). Two regression trends, in India, suggested an inflection point beyond which unit costs increased.</p> <p>Conclusion</p> <p>Unit costs decrease with scale across a wide range of service types and volumes. These country and intervention-specific findings can inform projections of the global cost of scaling up HIV prevention efforts.</p

Evidence for scaling up HIV treatment in sub-Saharan Africa: A call for incorporating health system constraints.

Jan Hontelez and colleagues argue that the cost-effectiveness studies of HIV treatment scale-up need to include health system constraints to be more informative

HIV prevention costs and program scale: data from the PANCEA project in five low and middle-income countries.

BackgroundEconomic theory and limited empirical data suggest that costs per unit of HIV prevention program output (unit costs) will initially decrease as small programs expand. Unit costs may then reach a nadir and start to increase if expansion continues beyond the economically optimal size. Information on the relationship between scale and unit costs is critical to project the cost of global HIV prevention efforts and to allocate prevention resources efficiently.MethodsThe "Prevent AIDS: Network for Cost-Effectiveness Analysis" (PANCEA) project collected 2003 and 2004 cost and output data from 206 HIV prevention programs of six types in five countries. The association between scale and efficiency for each intervention type was examined for each country. Our team characterized the direction, shape, and strength of this association by fitting bivariate regression lines to scatter plots of output levels and unit costs. We chose the regression forms with the highest explanatory power (R2).ResultsEfficiency increased with scale, across all countries and interventions. This association varied within intervention and within country, in terms of the range in scale and efficiency, the best fitting regression form, and the slope of the regression. The fraction of variation in efficiency explained by scale ranged from 26-96%. Doubling in scale resulted in reductions in unit costs averaging 34.2% (ranging from 2.4% to 58.0%). Two regression trends, in India, suggested an inflection point beyond which unit costs increased.ConclusionUnit costs decrease with scale across a wide range of service types and volumes. These country and intervention-specific findings can inform projections of the global cost of scaling up HIV prevention efforts

Evidence for scaling up HIV treatment in sub-Saharan Africa: A call for incorporating health system constraints

<p>Evidence for scaling up HIV treatment in sub-Saharan Africa: A call for incorporating health system constraints</p