Tropical Anemia: One of Africa's Great Killers and a Rationale for Linking Malaria and Neglected Tropical Disease Control to Achieve a Common Goal

Abstract

With more than 1 million child deaths annually, malaria remains the single leading killer of young children in subSaharan Africa [1]. Millions more young children survive, but still suffer from severe anemia and permanent neurological damage [1], as well as more subtle neuropsychiatric disturbances including impaired cognition and memory [2]. Malaria in pregnancy is also a major cause of maternal deaths and low birth weight [3], and together these maternal and child health effects account for huge economic losses that trap families in poverty [4]. As a result, malaria is now considered one of the key forces preventing the development of the African continent [4]. In response to a growing malaria crisis, the Bill & Melinda Gates Foundation recently announced an ambitious program of expanded malaria control, with a long-term goal of malaria eradication [5]. The major elements of expanded malaria control include strengthening of prevention and treatment programs worldwide through the Global Fund to Fight AIDS, Tuberculosis and Malaria, the United States President’s Malaria Initiative, the World Bank Malaria Control Booster Program, scale-up of national control programs [5], coordination through the Roll Back Malaria Partnership based at the World Health Organization (WHO) [6], and advocacy by Malaria No More and other organizations [7]. In the early 1970s, an intensified effort to interrupt the transmission of malaria was conducted in a group of villages near the town of Garki in northern Nigeria [8]. Through household spraying, mass drug administration, and other measures, there was a temporary reduction in malaria deaths, but overall the Garki Project showed that interrupting malaria transmission was not possible even when a full armamentarium of control tools was applied [8]. An important difference between then and now is the availability of long-lasting insecticide-treated nets (LLITNs) and artemisinin combination therapy (ACT)-based treatments, in addition to the increased willingness to deploy indoor insecticide spraying [1]. However, it is unclear whether even the deployment of these new control tools will directly lead to total success in malaria control because of the threat of emerging insecticide resistance to pyrethroids and the potential for emergence of artemisinin resistance [1,9,10]. Also, parallel efforts will be required to strengthen Africa’s weakened health systems [11,12], which today suffer from widespread malaria misdiagnoses in endemic areas [13] and a lack of access to essential medicines and LLITNs [14]. Accordingly, WHO and other organizations are embarking on renewed efforts to strengthen health systems in Africa and elsewhere [15], while product development partnerships have evolved in a concerted push to accelerate the development of additional new malaria drugs and insecticides, and safe and effective antimalaria vaccines [1,5,16]. There is yet another promising, low-cost and highly cost-effective, and complementary approach for potentially reducing the morbidity of malaria in sub-Saharan Africa, which builds on existing efforts and could be implemented for as little as US$0.50 per person per year or less than 10% add-on to projected malaria control costs [17–20]. In sub-Saharan Africa, where more than 90% of malaria deaths occur, children and pregnant women are simultaneously infected with both malaria and a group of other parasitic diseases, known as the neglected tropical diseases (NTDs). The major NTDs in sub-Saharan Africa include hookworm infection (198 million cases) and other soil-transmitted helminth infections such as ascariasis and trichuriasis (173 million and 162 million cases, respectively), schistosomiasis (166 million), trachoma (33 million), lymphatic filariasis (46 million), and onchocerciasis (18–37 million) [17,18]. There is evidence that some of these NTDs exert an adverse influence on the clinical outcome of malaria in childhood and in pregnancy [21–24], and even possibly on malaria transmission [25]. Shown in Figure 1 is a previously published map demonstrating the geographic overlap and co-endemicity of falciparum malaria and