To the Editor: Hotez et al. (Sept. 6 issue)1 present an excellentreview of current global approaches to neglected tropical diseases.However, vigilant ongoing (post-intervention) surveillance toensure that these diseases do not rebound should not be ignored.The integration of disease-control programs using a "rapid-impactpackage of drugs" is a feasible and probably cost-effectiveway to improve the quality of life for billions of people. Theauthors advocate monitoring and evaluation to judge the successof these programs but do not emphasize ongoing surveillance.Although surveillance may present a resource challenge in manyenvironments, it also poses a statistical challenge as theseheterogeneously distributed parasitic diseases become less common.A comprehensive, integrated surveillance plan should be incorporatedinto the cost estimates for the control or elimination of neglectedtropical diseases. New approaches for determining the burdenof these diseases as they become less prevalent should includeimproved diagnostic tools and novel epidemiologic techniques.
Clare Huppatz, B.M., B.S., M.P.H. National Centre for Epidemiology and Population Health Canberra 0200, Australia clare.huppatz{at}hnehealth.nsw.gov.au
David N. Durrheim, M.B., Ch.B., Dr.P.H. Hunter Medical Research Institute Newcastle 2310, Australia
References
Hotez PJ, Molyneux DH, Fenwick A, et al. Control of neglected tropical diseases. N Engl J Med 2007;357:1018-1027. [Free Full Text]
The authors reply: Huppatz and Durrheim comment on the needfor surveillance. For the neglected tropical diseases, controland surveillance strategies are determined by the epidemiologyand by the precise objectives of the intervention. For example,human African trypanosomiasis was controlled yet resurged duringthe period from the 1960s to the 1990s in Angola, DemocraticRepublic of the Congo, and Sudan, because surveillance stopped,health systems collapsed, and the mobile-team approach was abandoned.1Today, human African trypanosomiasis is again under control,and effective surveillance is crucial in order to avoid a newresurgence. In contrast, soil-transmitted helminthiasis andschistosomiasis require regular preventive mass chemotherapyto reduce severe morbidity, and subsequent monitoring of lotquality assurance sampling is enough.2,3 With lymphatic filariasis,onchocerciasis, and trachoma, surveillance after control mustmonitor reduction of transmission. The critical tools referredto by Huppatz and Durrheim are being developed or deployed.However, cost and expertise are constraints on routine use,because health systems are overburdened and human resourcesare scarce where neglected tropical diseases are prevalent.Sadly, introducing routine surveillance of neglected tropicaldiseases in health management information systems will be challenging,given the diversity of epidemiology and health systems.
David Molyneux, Ph.D., D.Sc. Liverpool School of Tropical Medicine Liverpool L3 5QA, United Kingdom
Alan Fenwick, Ph.D. Imperial College London London W2 1PG, United Kingdom
Lorenzo Savioli, M.D., M.Sc. World Health Organization 1211Geneva, Switzerland
Brooker S, Kabatereine NB, Myatt M, Stothard JR, Fenwick A. Rapid assessment of Schistosoma mansoni: the validity, applicability and cost-effectiveness of the Lot Quality Assurance Sampling method in Uganda. Trop Med Int Health 2005;10:647-658. [CrossRef][ISI][Medline]
Preventive chemotherapy in human helminthiasis — coordinated use of anthelminthic drugs in control interventions: a manual for health professionals and programme managers. Geneva: World Health Organization, 2006.
Previous
