“Studies like this demonstrates the value of drug resistance surveillance projects. By understanding the prevalence of drug resistance together with drug usage patterns we can develop better stewardship practices that will extend the shelf-life of not just antimalarial drugs, but antimicrobial drugs in general.”
While in Zambia I had the wonderful though brief o6pportunity to visit the Tropical Diseases Research Center (TDRC) and the University Teaching Hospital (UTH) of the University of Zambia. Unfortunately at both institutions photo opportunities were limited either because of time restrictions or because of the risk to patient confidentiality. However, at both institutions I was able to sit down and chat with some researchers that have dedicated themselves to fighting antimicrobial resistance (AMR) and get an overall idea of the research activities that take place at these institutions, and the challenges and rewards of working in a developing nation such as Zambia.
The main offices of the TDRC are located within the Ndola Central Hospital in Ndola, the mining capital of Zambia. Geographically Ndola is situated right at the southern edge of the central African tropics, a region known for tropical diseases such as malaria, schistosomiasis, trypanosomiasis, filariasis and more. These diseases pose a major threat to the health of people living in the tropics, and is the reason the TDRC was established in 1975 by the World Health Organization (WHO) as one of three tropical disease rsearch centers worldwide.
Dr. Ray Handema, the Deputy Director at the TDRC, told me that the TDRC used to be home to some great scientists, but they have all long-since retired and those shoes were never filled. Consequently research activities and outputs at the TDRC decreased and it went through a difficult period. However, now under leadership of Director Dr. Modest Mulenga and Deputy Director Dr. Ray Handema the TDRC is making a comeback. It has set up a Staff Development Programme to do exactly as the name suggests and shifted its research programmes towards more contemporary threats such as tuberculosis, HIV/AIDS, diarrheal diseases, micronutrient deficiency diseases and the safety and benefits of traditional medicines. However, malaria remained a major research focus as it is still one of the greatest threats to human health in (sub)tropical Africa.
Through the Staff Development Programme researchers at the TDRC have learnt to embrace the scientific culture of competitive grant writing to obtain funding for research and technology acquisition from national funding agencies, such as the National Scientific and Technological Council and Ministry of Science and Technology, and foreign agencies such as the Gates Foundation (USA), the Medical Research Council (UK), USAID (USA) and the Welcome Trust (UK).
One of the young Staff Development Fellows I had the pleasure of meeting was Mr. Sydney Mwanza. His research interests are diverse, but a high priority for him is the prevalence of drug resistance in Plasmodium falciparum, the parasite that causes malaria. Sydney explained that chloroquine used to be the main drug for the treatment of malaria. However, in 2003 the P. falciparum isolates from approximately 60% of the patients were resistant to chloroquine. Consequently chloroquine was substituted with coartem, a combination drug of artemether and lumefantrine. Now, just over a decade later, Sydney and his colleagues have found that chloroquine resistance was no longer present when they screened samples from patients living in Nchelenge, a region with an extremely high prevalence of malaria compared to the rest of Zambia.
If funded successfully, the TDRC will expand its study on chloroquine resistance nation-wide to determine whether chloroquine can be brought back as a malaria treatment, but with lessons learnt. For example, resistance to chloroquine evolved rapidly because it is a single drug that was used as the only treatment for malaria. The evolution of resistance to coartem has been much slower because it is a combination of two different drugs that target different regions of the P. falciparum parasite. Thus, if chloroquin is brought back as an antimalarial treatment it will most likely be as a combination drug and probably in rotation with other drugs.
Studies like this demonstrates the value of drug resistance surveillance projects. By understanding the prevalence of drug resistance together with drug usage patterns we can develop better stewardship practices that will extend the shelf-life of not just antimalarial drugs, but antimicrobial drugs in general.
To be continued.