Introduction to TDR

[Dora Ann Lange Canhos]

An introduction to the UNDP/World Bank/WHO Special Programme for
Research and Training in Tropical Diseases (TDR)

9 July 1993

The target diseases

TDR's target diseases are malaria, schistosomiasis (bilharzia or
"snail fever"), leishmaniasis, African trypanosomiasis (sleeping
sickness), American trypanosomiasis (Chagas disease), lymphatic
filariasis (which leads to elephantiasis), onchocerciasis (river
blindness), and leprosy. Almost 500 million people, almost all
of them in the developing countries, suffer from these diseases,
which can cause terrible anguish, deformity, and death. At the
same time they cause considerable economic losses, and frequently
interfere with development projects (particularly water projects
such as dams and irrigation schemes, and planned and unplanned
forestry).

The death toll from the diseases - particularly among children
from malaria in Africa - is expected to double by 2010, possibly
reaching four million lives a year, unless radical solutions are
found. Population increase, the spread of parasite resistance,
mass migrations, environmental disturbance, and disruption of
control programmes through economic devastation, civil unrest and
wars, all contribute to the tropical disease problem.  

TDR's objectives

The UNDP/World Bank/WHO Special Programme for Research and
Training in Tropical Diseases was set up in 1975 with a double
mandate to:

1. Develop new methods of preventing, diagnosing, and treating
tropical diseases, methods that would be applicable, acceptable,
and affordable by developing countries, require minimal skills
or supervision and be readily integrated into the health services
of these countries.

2. Strengthen - through training in biomedical and social
sciences and through support to institutions - the capability of
developing countries to undertake the research required to
develop and apply these new methods.

In this work, TDR collaborates closely with WHO's Division of
Control of Tropical Diseases (CTD), and with many other WHO
programmes and outside bodies concerned with tropical disease
research and control.

How TDR operates

TDR acts to some extent like a research council, supporting
investigator-initiated projects selected by peer-review, and to
some extent as a pro-active agency commissioning the research
required to reach its objectives. Its budget for 1994-95 is
US$66.7 million, some 70% of which will be spent directly on
project support. A quarter of TDR's funds goes to research
capability strengthening (RCS) in developing countries. This RCS
work is being increasingly combined with the performance of
needed research: "training by doing".

Over the eighteen years of TDR's existence, a large number of
drugs, diagnostic techniques, vector control agents and other
products have been developed, and in conjunction with national
and international control programmes there has been considerable
success in applying these to reduce (or potentially reduce) the
burden of some of the tropical diseases - notably leprosy,
onchocerciasis, and Chagas disease. The other diseases still pose
major problems, either globally or regionally. 

TDR's research targets, and the appropriate management and
decision making structure to reach those targets have been
thoroughly reviewed during 1992-93. A new structure, which will
give the programme greater focus on priority targets, and more
flexibility to identify and respond to the practical health and
control needs of populations, will operate from 1st January 1994.

In the new structure TDR's research is to be divided into three
basic functional areas: "strategic" research, "applied field
research" and "product research and development".

Strategic research

TDR defines "strategic research" (SR) as basic research, usually
on the diseases, the parasites that cause them, or the vectors
that carry them, aimed at a specified long-term goal in tropical
disease control - such as the genetic engineering of the mosquito
to make it unable to carry malaria. The amount of strategic
research supported by TDR is decreasing, but not vanishing;
important opportunities must always be grasped, subject to the
availability of funds. 

Applied field research

The research, development and even introduction of a new tool
does not automatically lead to improved control. Experience has
shown that the ultimate success of TDR's efforts to control
tropical diseases depends on social and economic factors in the
endemic communities and on control programmes' awareness of
people's needs, perceptions and wishes. Thus there is an urgent
need for applied field research to develop cost-effective and
sustainable control strategies which are based on a thorough
understanding of social and economic factors, on the needs of the
people in the endemic communities as identified by them, and on
the availability and use of health facilities.
  
Thus TDR's applied field research (AFR) will be a crucial area
in the new Programme structure. AFR will address a multitude of
practical community-level and health-system control questions
which will help apply effectively the products of earlier
research and will provide new appropriate directions for
research. Around a dozen AFR Task Forces are being established,
for example, on operations research in Chagas disease and in
onchocerciasis, on women and tropical disease, on the use of
bednets, on an integrated approach to the sick child, of tropical
diseases and health financing.

Product research and development

TDR's product research and development (PRD) covers the process
of transforming scientific knowledge into usable disease control
products, through Phase I-IV field trials, registration and the
negotiation of production at an affordable price. The Product
Development Unit focuses most resources on a short list of a few
such projects, such as artemisinin derivatives, tumor necrosis
factor antagonists, and transmission-blocking vaccines for
malaria, and the co-delivery of praziquantel and albendazole for
helminth infections.

TDR's particular strengths

As part of the United Nations system, TDR enjoys a world view of
the tropical disease scene and the standing conferred by a lack
of partisan or profit-making motivation. These assets explain in
large measure TDR's rapid success in creating an international
network of over 5000 scientists, which gives it access to a broad
range of expertise and scientific disciplines.

Through its WHO connection, TDR has ready access to programmes
and units working in related fields and most importantly, with
its new focus on the field and on national control programmes -
to WHO's 185 Member States. TDR can call on government support
in endemic regions in order to engage populations and facilities
in multi-centre field trials, rapidly and at very low cost.

Further information

Further information is also available from TDR Communications,
World Health Organization, 1211 Geneva 27, Switzerland.