Team for Applied Research Generating Effective Tools and Strategies for Communicable Disease Control
Intermittent Preventive Treatment for African Children: where and how should it be applied?
Intermittent Preventive Treatment of infants (IPTi) involves giving anti-malarial drugs to infants as a preventive measure, regardless of whether or not they have malaria. TARGETS researchers have contributed to the development of an online tool that will help Malaria Control Programme Managers decide which areas of their country would be most appropriate for the cost-effective deployment of IPTi.
Informing policy decisions at national and international level
Findings from a project evaluating IPTi have been synthesised to develop an easy-to-use internet-based tool targeted at policy-makers. The tool provides the user with tangible information at a sub-national level. It enables users to select the level of malaria transmission intensity, seasonality, DPT3 schedule and expected IPTi coverage, giving existing data to support choices where available. The tool then generates a graph of the expected age-pattern of non-severe malaria, severe hospital admissions and malaria-diagnosed deaths, plus the corresponding proportion of these that would occur in infants aged 3-12 months. Programme managers can also access a table of the predicted number of cases that could be averted by implementation of IPTi.
Deciding on the best approach for tackling Malaria in infants
The World Health Organisation (WHO) Technical Expert Group has recommended that IPTi can be considered for implementation in areas of sub-Saharan Africa with moderate to high malaria transmission. When the WHO policy-making process is complete, countries will need to make evidence-based decisions on whether to implement IPTi nationwide, or in which select regions. The IPTi web-tool provides the information needed to make this decision. The tool is being further developed to incorporate cost-effectiveness data, and was showcased to policy makers at the IPTi Consortium Annual General Meeting in Geneva in January 2009.
The project assessed the applicability of IPTi under different epidemiological conditions using two approaches. The first involved a pooled analysis of research data on (i) non-severe malaria (from community-based studies); (ii) severe malaria hospital admissions (from hospital-based studies); and (iii) malaria-diagnosed deaths (from demographic surveillance systems), under different intensities and seasonality of malaria. This analysis found that the burden of non-severe malaria was relatively evenly distributed throughout childhood (0-10 years), whereas severe malaria hospital admissions were more frequent in young children. Malaria-diagnosed deaths were skewed to the very young. All outcomes showed a shift towards younger age groups with increasing transmission intensity, although this effect was dampened in areas with markedly seasonal transmission.
The second approach to assessing the applicability of IPTi was the development of a stochastic mathematical model of malaria transmission, based on the findings of three randomised controlled trials of malaria. This model was then used to predict the actual number of cases likely to be averted by implementing IPTi under different epidemiological conditions. In agreement with the findings of the age-pattern work (above) the model predicted that IPTi would avert more cases with increasing transmission intensity and would have a greater relative effect with increasing severity of the outcome (as the burden shifts towards the IPTi target age-group).
The project was a collaboration between researchers at the London School of Hygiene and Tropical Medicine and the Swiss Tropical Institute Switzerland. The lead TARGETS researcher is Dr Ilona Carneiro with Lucy Smith (LSHTM). The project was part of the IPTi Consortium, which brought together researchers from different countries, institutions and with different technical and professional backgrounds.