Neglected Tropical Diseases: Moving Beyond Mass Drug Treatment To Understanding The Science

Abstract

Neglected tropical diseases (NTDs) represent a major health burden in many developing countries. To date, global efforts to control thirteen parasitic and bacterial infections that affect more than 1.4 billion people have relied on mass drug administration. This singular approach should now be expanded to a more comprehensive suite of tools including coordinated community-based programs, vector control, local training, education, and environmental change. In addition, an intensive basic research agenda is urgently needed to develop effective diagnostic, preventive, and therapeutic interventions to stay one step ahead of the evolutionary adaptation tactics of disease-causing microbes and parasites.

Global burden, distribution, and interventions for infectious diseases of poverty

“…These include preventive chemotherapy; innovative and intensified disease-management; vector control and pesticide management; provision of safe drinking water, basic sanitation and hygiene, and education; and veterinary public health services [29]. Mass drug administration (MDA) has been a major approach to combat helminthiasis including ascariasis, trichuriasis, hookworm, schistosomiasis, LF, onchocerciasis, and trachoma in developing countries [30]. There is evidence suggesting significant benefits of treating diagnosed cases [31,32], and these medicines are not only effective but also cost efficient.…”

Role of antibody dependent cell mediated cytotoxicity (ADCC) in Sm-p80-mediated protection against Schistosoma mansoni

“…Control programs implemented in schistosome-endemic areas to reduce mortality and morbidity associated with schistosome infections have so far produced suboptimal results; the disease has not been contained and continues to spread to new geographic areas [1–5]. An effective anti-schistosome vaccine would immensely reduce the morbidity associated with schistosomiasis through induced immune responses leading to decrease in parasite load and reduced egg production [6–11].…”

Balance between clinical and environmental responses to infectious diseases

“…He is treated and sent home only to be reinfected in his still-contaminated community. This contrasting response to chemical and infectious environmental hazards is not an isolated example; rather it is a reflection of the largely clinical orientation of many global infectious disease control efforts, 1 despite the potential for environmental interventions to sustainably and cost-effectively limit re-exposure to environmental pathogens. 2 We argue that the management of environmental pathogens— currently dominated by clinical intervention—could benefit from an improved balance between clinical response and environmental action.…”

“…Infections are treated using antihelminthic agents, yet treated patients return to a contaminated environment and re-infection is pervasive. For many STHs such as hookworm and Ascaris , which persist in the environment, a cycle of deworming and reworming is accepted as a reality in current global control campaigns, 1, 6 and some have argued that the predominance of drug therapy must give way to more comprehensive measures that include environmental and other interventions, 1, 2, 6 particularly as repeated reinfection can itself lead to more severe clinical outcomes in some cases. 7 The goal of a more balanced, integrative approach is to minimize the repeated re-exposure to environmental hazards that occurs when mitigation focuses solely on clinical therapy; this in turn would minimize populations being sent right back "into the environment where the trouble originally started."…”

“…17 These activities expand on China's chemotherapy-based schistosomiasis control programs, 17, 18 and efforts in other global settings could learn from China's success balancing antihelminthic treatment with environmental interventions. 1 …”