A new tool to track drug-resistant malaria parasites in Africa

Summary

The malaria resistance is a major public health problem in African regions. Drug resistance markers are used to monitor the emergence and spread of parasite. The drug resistance markers compromised of parasite that interact with drugs. Various technical improvements in methods have enabled identify the parasite DNA. However, current tools used to measure drug resistance have some limits. Our project has focused on developing a better tool that can overcome this limitation for more sensitive and cost-effective surveillance to better inform the National Programs fight against malaria.

Background
Plasmodium falciparum,  the most deadly species of malaria, displays a wide variety of resistance mechanisms. In the absence of a vaccine at 100%, current malaria control methods rely on drug prevention and through minimizing exposure to mosquitoes. Patients are often infected with more than one distinct parasite and this may influence disease development, transmission rates and the spread of drug resistance. Mixed infections have been reported in greater than 50% of sampled in high malaria tramsmission. Common tools based of anti-malarial resistance has limit to assess the mixed infections, and must be improved for better surveillance and control of malaria strategies. We investigated a new approach that that can overcome these linits to evalute the mixed infection based on the quantification of drug resistance markers. This innovative approach will allow the proportion of different markers of drug resistance of parasites to be estimated, as well as the relative burden of individual drug resistance. Furthermore, this approach is more cost-effective and more sensitive to detect the emergence and spread of parasite resistant which threaten public health.

Description of study

Seasonal malaria chemoprevention (SMC) is a malaria control strategy to protect children under 5 years in Africa, consisting of monthly administration of full courses of sulfadoxine-pyrimethamine plus amodiaquine in high transmission season. One of the methods to monitor the effectiveness of this strategy in mass campaign is the drug resistance. I hope to develop a standardized surveillance tool for drugs used in SMC. As you know, Laboratory of Malaria Immunology and Vaccinology (LMIV), U.S. National Institutes of Health (NIH) is one of the world leaders in malaria research, providing an opportunity for me to further develop specialized skills and build a successful partnership in the future. My main goal at the LMIV was to receive training in order to monitor the drug resistance in the context of SMC. Finally, I developed a new method of drug resistance by bioinformatic approach

Outcomes

The present study has shown that this bioinformatic approach is a reliable and less expensive than convention method and that could be used to monitor the malaria drug resistance. In the last decade, it has been complicated to use the bioinformatics tool in Africa. More recently, it has become easy and inexpensive, and many labs in Africa now have bioinformatic platforms. Our new technique offers practical advantages that can be applied meaningfully to the laboratory activities and providing a simplified model using assays to conduct surveillance for drug-resistant of malaria in Africa. Our results demonstrate is an effective approach for population-based surveys that characterize mixed infections, and thereby may provide an earlier signal to public health officials. Compared to the convention approach, this bioinformatic method may yield a more accurate estimate of drug-resistant of the total parasite reservoir in the community.

Lessons
The result of research is a dynamic process. We should not follow the scientific results blindly but understand the mechanism and if possible, to make your small contribution for amelioration. This is what will move us forward. We sincerely believe that the WHO should reflect on our research results as an additional tool in the fight against malaria resistance.

About Hamma Maiga
Hamma Maiga is a Malian molecular biologist and African Postdoctoral Training Initiative (APTI) Fellow based at the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institute for Public Health of the Ministry of Health in Mali. APTI is supported by the U.S. National Institutes of Health (NIH) and the Bill & Melinda Gates Foundation. APTI trains African researchers in global health and develops their skills in clinical and translational research.