The Importance of Targeting Parasitic Neglected Tropical Diseases (NTD)
The purpose of this website is to introduce some basic concepts in future treatment approaches to parasitic disease. Our website will focus on 10 parasites that are considered high priority by the United Nations and the Global Network for Neglected Tropical Disease Control (GNNTDC). Our research does not include malaria, which will be covered elsewhere. We will discuss NTDs within the context of the Disability Adjusted Life Year (DALY), a method of quantifying and standardizing disease burden and intervention efficacy that is used in assessing priorities and funding allocation. From there we will introduce the main diseases, their current treatment strategies, and promising research into future solutions through vaccine or drug therapies. Links to useful websites on this topic are also included.
Only 10% of global health research spending is directed towards “neglected diseases of the poor,” even though these diseases, including parasitic infections, account for roughly 90% of global disease burden (Global Forum). Aware of this situation, the United Nation’s Ad Hoc Committee on Health Research Relating to Future Intervention Options proposed a methodology for allocating research and development resources in 1996. The World Health Organization’s (WHO) strategy for 2000-2005 implemented these recommendations and called for more evidence-based strategic planning for allocation of funds (Remme). Included in this decision-making process were the following factors:
(1) Size of disease burden and epidemiological trends
(2) Reasons for continued persistence/what is the current disease control strategy
(3) What are major problems and challenges to disease control?
(4) What research is needed to address these problems and challenges?
(5) What is currently being done in research and development? What research opportunities exist?
The UN Development Program, World Bank, and WHO Special Program for Research and Training in Tropical Diseases (TDR) and the GNNTDC have subsequently identified the following parasitic diseases as primary targets in intervention research.
Most Wanted:
(Remme, Stoever)
*These are only a list of the most pressing parasitic (helminthes/protozoan) infections, this site does not go into discussions of viral, fungal or bacterial infections.
what is a daly?
The Disability Adjusted Life Year (DALY) is a disease burden measurement developed and adopted by the World Health Organization in the 1990’s. Its goal is to generate a standard value for the effect of a given disease based not only on whether a person lives or dies, but also the disease’s effect on the individual’s overall well-being.
In terms of calculating this value, the DALY is the sum of years of life lost due to early death (YLL) and the years lost due to disability (YLD) for a given health condition.
In a formula: DALY= YLL +YLD
YLL is the number of deaths (N) in a given region or country multiplied by the standard life expectancy for that age group and sex, or:
YLL= N x Life expectancy (L)
YLD is temporal in the sense that the number of cases of a given disease in a specific timeframe (incidence, I) is multiplied by the average duration of a disease before remission or death (l), multiplied by the disability weight (DW) or:
YLD= I x l x DW
Disability Weights are commonly agreed on standardized values for a given condition that fall within a continuum from 0 (perfect health) to 1 (signifying death). Blindness for example falls at 0.6. (UNC’s African Sleeping Sickness Initiative)
Critics of the DALY claim that it disregards political, economic, social and structural conditions faced by different people across the world. One author made the point that the DALY disregards the fact that a blind person in England has much more resources available to him than someone with an identical condition living in Niger, thus making the Englishman’s disability much less of a hindrance to normal life (Reidpath). Regardless, this rubric is widely used as a bench-mark for assessing the burden of disease and how crippling it is to the affected populations.
One DALY is equivalent to one year lost of full, perfect health. This metric also helps to elucidate gaps between the current health status and an ideal world free of disease and disability.
(Discussion of DALYs from WHO website)