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|Action plan for the
reduction of reliance on DDT in disease vector control, WHO/SDE/WSH/01.5
WHO Action Plan
Introduction | Components
| Timeframe |Objectives |
Immediate action | Medium-term
action | Long-term action | References
At the first meeting of the Intergovernmental Negotiating Committee
(INC) for an international legally binding instrument for implementing
international action on certain Persistent Organic Pollutants (POPs),
the World Health Organization, mandated by World Health Assembly
Resolution WHA50.13 (annex 1), proposed the development of an Action
Plan to support its Member States in making informed decisions
concerning the effect on disease transmission of a reduction and/or
elimination of DDT, under a future POPs Convention. Such a WHO Action
Plan would aim to increase public health staff awareness of the INC
process. Ultimately, the Action Plan would assist Member States in their
efforts to reduce their reliance on DDT use for public health purposes
without jeopardizing the level of protection offered by their vector
The Action Plan for the Reduction of Reliance on DDT in Disease
Vector Control presented in this document emerged from an expert
consultation held from 16 to18 June 1999 at WHO, Geneva (see Annex 2 for
the report of the consultation).
Three strategic principles have served as the basis for
developing and formulating the Action Plan. They are: involvement of
countries concerned, early identification of funding mechanisms and
The most recent recommendations concerning DDT use for indoor
residual spraying against malaria vectors date back to 1993. They list
well-defined conditions and a number of precautions (WHO, TRS 857,
1995). DDT is also used at times for the control of kala-azar (visceral
leishmaniasis), plague and tick-borne encephalitis, but is not formally
recommended by WHO for these purposes. In malaria control, it is used in
routine spraying operations, for prevention of disease transmission and
in epidemic situations. Some countries reserve the right to maintain
stockpiles of DDT for emergencies.
Preliminary data show that at least 24 countries use DDT for vector
control. Yet, there is a great deal of variability in the intensity of
its use. There is also a disparity between the geographical distribution
of DDT use for malaria control and the areas of the world where the
malaria burden weighs the heaviest.
The use of adulticides, including DDT, for indoor residual house
spraying to control vectors is just one of several possible components
of integrated vector management (IVM). In turn, IVM is just one
component of integrated disease management. The strategy for the
prevention and control of vector-borne disease places vector control in
the context of disease management and aims to seek tailor-made, flexible
solutions to local malaria problems. In addition to its main objective
of reducing disease transmission risks, another major goal of IVM is to
reduce the use of insecticides whenever possible. It promotes
decision-making criteria and management procedures that ensure the best
local mix of alternatives at a given place and time.
For the purpose of this Action Plan, alternatives are defined as:
- alternative products for chemical and biological control.
- alternative methods of vector control such as environmental
management and personal protection and
- alternative strategies that are based on scientifically sound
criteria, cost-effectiveness analysis, and a delivery system
compatible with current trends in health sector reform, including
decentralization of health services, intersectoral action at the
local level and subsidiarity in decision-making.
The concept of integrated vector management (IVM) as a sub-component
of disease management will provide the decision-making framework for
vector control in the future, including decisions on the use of DDT or
other adulticides. This management approach has been highly successful
in agriculture in the sustainable control of pests and in the reduction
of reliance on insecticides.
The three main instruments for achieving the goals of the
Action Plan are:
- Integral research and capacity-building to enable countries to
introduce sustainable vector control alternatives based on a reduced
reliance on insecticides including DDT,
- Country-specific exemptions in accordance with the procedures laid
down in Annex B, part II of the Stockholm Convention, and
- Appropriate and timely financial support and technical cooperation
for the implementation of the Action Plan.
It is recognised that there are several countries that continue to
rely on DDT for public health purposes and that these countries should
be allowed to do so until safe, effective and affordable alternatives
are available and operational.
This is in line with recommendations made at the 20th
Malaria Expert Committee meeting in October 1998 which, inter alia,
state: It is anticipated for some time to come that there will
continue to be a role for DDT in combating malaria, particularly amongst
the poorest endemic countries. Restrictions on DDT for public health use
contained in a future POPs Convention should therefore be accompanied by
technical and financial mechanisms to ensure that effective malaria
control is maintained, at least at the same level, through vector
control methods that depend less on pesticides in general, and on DDT in
particular." (WHO, TSR 892, 2000).
It has, therefore, been a fundamental principle in the development of
this Action Plan that any possible deadline in the POPs Convention
should relate not to the phase-out of DDT, but rather to the time at
which the financial, technical, and administrative tools are in place to
begin a transition from DDT to an integrated deployment of alternatives,
without any jeopardy to disease transmission risk. Thus, the original
IFCS requirement of reduction and/or elimination of DDT at no cost to
public health is fulfilled. In the final text of the Convention no such
deadline is included.
Furthermore, support for the Action Plan or for the assistance to
countries to make a successful transition to alternatives to DDT should
not be at the expense of financial resources earmarked for other
priority public health issues.
Taking into consideration the conclusions and recommendations of the
group of experts, WHO has developed the following Action Plan.
Components of the Action Plan
Based on the outcome of the expert consultation (Annex 2), five areas
of major importance for the implementation of the Action Plan were
identified. They include:
- Country needs assessment,
- Safe management of DDT stockpiles,
- Institutional research networks,
- Monitoring, and
Objectives and activities for each of these are presented below. In
addition, each activity has been earmarked as a immediate, medium- or
long-term action. The time frame does not foresee action for all areas
of importance under each time horizon.
The proposed endpoints for the activities are as follows:
- Immediate action - May 2001.
- Medium-term action - just prior to the POPs Convention taking
effect (i.e. after the government ratification threshold has been
passed), to report on progress to the first meeting of the
Conference of Parties to the Convention.
- Long-term action - on-going technical cooperation with interested
Member States among the Conference of Parties.
Country Needs Assessment
- Ensure that health concerns are mainstreamed in the POPs
negotiations in order to prevent any negative health impact as a
result of the Convention’s regulations concerning DDT.
- Provide a framework for a needs assessment in countries enabling the
transition towards a reduced reliance on insecticides, while
maintaining and, if possible, improving effective vector control.
- Provide incentives and leverage funds for strengthening the capacity
of governments to promote, utilize and evaluate vector control
Safe Management of DDT Stockpiles
- Prevent damage to the environment and minimise risk to human health.
- Develop criteria for decision making on options to use, reformulate,
repack, or dispose of DDT stocks.
- Establish a reliable and verifiable management process that clearly
defines the responsibility for stockpile management.
Institutional Research Network
- Formulate joint research projects of health and agriculture
scientists/research institutions on the development of integrated pest
and vector management strategies.
- Further develop, test and/or implement sustainable, environmentally
safe and cost- effective alternatives to the use of DDT for vector
- Assist Member States in programming, monitoring and reporting
information on the following DDT related issues:
- Human exposure to DDT.
- Public health outcomes of DDT reduction.
- Production, storage and usage of DDT.
- Efficacy and appropriateness of DDT in areas where it
continues to be used.
- Efficacy and appropriateness of alternatives to DDT,
including integrated vector management (IVM).
- Provide background information on the POPs negotiations and on DDT
to the health sector.
- Ensure that the health sector's views are known to delegations to
the POPs negotiations.
Country Needs Assessment
Prepare an inventory of current use, trends and regulatory status of
To better understand what support Member States may need in order to
reduce their reliance on DDT in vector control programmes, it will be
necessary to review and update current information on the use of DDT in
vector control. This will be done through the activities of WHO, FAO,
and Global Crop Protection Federation (GCPF). The main categories of DTT
- DDT in routine vector control programs.
- DDT in epidemic outbreaks; DDT reserved for epidemics only.
- DDT as an integral component of a disease management program such
as is embodied in the Global Malaria Control Strategy.
Promotion of and incentives for the development of national action
plans for the reduction and/or elimination of DDT
Country needs to facilitate a successful transition to a situation of
reduced reliance on DDT in vector control should be assessed through
Member State consultations at the WHO regional level or in different
Safe Management of DDT Stockpiles
Co-operate with concerned organizations (FAO, UNEP) and
non-governmental partners including the GCPF
A review, update and expnasion of inventories of DDT stocks should be
combined with efforts to encourage corporate partnerships that aid and
fund proper storage and disposal of DDT.
Ensure a global program of monitoring exposure of DDT in humans
WHO, through the International Programme on Chemical Safety (IPCS)
should promulgate standards, and identify regional laboratories to
perform clinical and environmental sampling and analyses.
Furnish the appropriate information to the health sector to allow for
balanced decisions based on "informed consent"
The provision and dissemination of appropriate information consists
of the following elements:
- Information on the environmental and human health impact of DDT.
- Information on alternatives to DDT for disease prevention and
control, including IVM.
- Estimates of the global mortality and morbidity (or DALYs) that
are saved through programmes for the control of malaria and other
vector-borne diseases, including the use of DDT indoor residual
- Information on the potential exemptions for DDT use in the POPs
WHO, the Secretariat of the Convention and industry through GCPF all
have a role to play in this activity. Appropriate information should
also be made available to NGOs.
Provide the health sector with the opportunity to have its
views represented in the INC process and after
Firstly, participation of health ministries in the INC process should
be encouraged through provision of information as described above, and
the use of Notes Verbales of the WHO Director General and/or Roll
Back Malaria to Member States.
In addition, it can be propose to national governments and/or
Convention negotiating blocs (the WHO Regional Office for Africa,
CRULAC, G77, etc.) that they adopt a joint position on DDT reduction.
Action should also be undertaken to facilitate cooperation between NGOs
and ministries of health and/or Convention negotiating blocs.
The DDT issue in the context of the POPs negotiations should be made
a topic for internal discussions at WHO Regional Offices.
Country Needs Assessment
Inventory of current use, trends and regulatory status of DDT
The inventory of actual current DDT usage prepared under Immediate
Action should be expanded, taking into account the results of the
review of the indications of use. The following elements should be taken
- Decision-making criteria and procedures for the use of DDT in
vector control programmes.
- Regulatory procedures, and where appropriate, the legal basis for
the use of DDT.
- Amount of DDT actually used per year and where.
- Alternative vector control method(s) used.
Modalities for preparing the inventory should include a review of the
presently used DDT reporting systems provided by country vector control
programmes. Member States can furthermore be assisted in the development
of DDT inventory questionnaires through
- the promotion and improvement of the process for obtaining
information through questionnaires and other methods of data
- Conducting regional workshops on DDT inventory information
- Co-operation with FAO/UNEP in the collection of DDT use and
- Soliciting information/data on DDT use, and trends in future use
from industry through GCPF and from non-governmental and private
sector organizations engaged in market analysis.
Promotion and incentives for the development of national action plans
for the reduction and/or elimination of DDT
This activity will entail the identification and promotion of
incentives for the development of national action plans. It will also
provide guidance and technical assistance to Member States for the
development of national integrated disease control action plans.
Capacity building to promote, utilise, and evaluate
alternative methods for vector control
In a comprehensive way, this activity will:
- Assist Member States in the review and adjustment of their vector
control policies and programmes in the context of health sector
reform, that will lead to a more decentralized, intersectoral
delivery of vector control services.
- Promote, test, consolidate, and validate experiences on the use of
alternatives for the control of malaria and other vector-borne
diseases in areas where there is reliance on DDT.
- Train health sector personnel in the management and
decision-making for integrated vector management. Include
municipality level guidelines for the selection and evaluation of
vector control options.
- Strengthen peripheral mechanisms (e.g. community participation,
decentralised funding) for vector-borne disease control programme
Validation of effectiveness of different vector control interventions
and analysis of their cost effectiveness
Past and present vector control programmes will be reviewed as to
their (cost-) effectiveness and sustainability. Alternative disease and
integrated vector management strategies will be designed, implemented
and evaluated. In the context of comparative studies, cost-effectiveness
analysis of DDT and alternatives in different settings will be
Safe Management of DDT Stockpiles
Safety measures - co-operation with organizations concerned (FAO,
UNEP) to provide assistance to Member States
Based on the inventory preparation and partnership promotion under
Immediate Action, this are of activity will now see action to assure
safe containment of stockpiled DDT.
Evaluation will take place of security of local stockpile management
in order to prevent illegal diversion. Designation of stockpile
management responsibility to appropriate organizations will be
Co-operation with organizations concerned (FAO, UNEP) to review and/
or develop the criteria if there is to be disposal of a stockpile of
DDT: (i.e. FAO Pesticide disposal series No.4, 1996) along the
- Materials meeting WHO criteria for use in public health.
- Materials able to be reformulated and repacked to meet WHO criteria.
- Materials which must be destroyed.
Institutional Research Network
Research on the use of alternative vector control methods and
strategies should be promoted through inter-institutional co-operation.
Primary research should be dedicated to:
- The development of integrated pest and vector management strategies
(IPM/IVM). Joint agriculture (FAO) and public health (WHO) initiatives
should be developed, including research on alternatives to pesticides
and pesticide resistance management.
- Design and implement pilot integrated vector management programmes.
Implementation should be based on a review of ongoing IVM/IPM
programmes and locally appropriate technology.
- Conduct research on managerial support systems that facilitate the
implementation of IVM.
- Conduct research on the incorporation of risk assessment and
management measures into infrastructure projects.
In addition, research should be promoted on
- The cost-effectiveness of pyrethroids compared to DDT and other
adulticides for indoor residual house spraying, in operational
- Insecticide resistance management.
- Impregnated mosquito nets as an alternative to DDT. Such research
should examine their effectiveness, sustainability, and
affordability when provided free for users as a public health
measure or commercially under a social marketing scheme.
- Pesticide pricing practices and patents expiration, and options
for local production with a view to making alternatives affordable
in the poorest countries.
- The potential and operational implications of environmental
management for malaria reduction in urban and rural areas.
- The impact of selective biological control agents on disease
vectors (e.g., applicability of recent positive results with fish in
- Social and behavioral research on perceived needs and willingness
to participate in mosquito / disease control.
- The evaluation of nuisance mosquito control as an incentive for
- The use of biological control such as Bacillus sp., fungi,
nematodes, copepods and botanicals in routine programs. Such
research should examine their applicability and local production
Human exposure to DDT - assist in the development of a global program
of monitoring exposure of DDT in humans.
Under the aegis of IPCS, this area of activity will see revision,
updating and standardization of protocols for analyses and data
Public health outcomes of DDT reduction - ensure that DDT reduction
is not causing adverse impacts on the health status.
A number of activities are foreseen under this heading:
- Revise, update, and standardize protocols for analyses and data
reporting (IPCS, leverage national technical standards).
- Assist countries in monitoring transmission indicators in
locations where DDT is being reduced (WHO Regional Offices,
ministries of health).
- Assist countries in developing the capacity for rapid analysis of
data collected in the monitoring programme.
Monitor the efficacy and appropriateness of DDT in areas where it
continues to be used. Ensure that continuing the use of DDT is bringing
positive public health gains.
WHO, together with minstries of health and where appropriate the
Secretariat of the POPs Convention, will work towards the development of
a comprehensive approach to evaluating the use of DDT for vector-borne
disease control, including:
- A DDT guidance manual based on existing WHO guidelines for
appropriate use of DDT in public health.
- Dissemination of this manual through national disease control
capacity building programmes.
- Training exercises to teach public health personnel how to educate
others on the use of the guidance manual as part of vector-borne
disease capacity building.
- Compliance of national governments, as required by the Convention
to report public health uses of DDT, preferably in advance of the
use although this is not prescribed by the Convention.
- Audit national proposals for use of DDT for consistency with the
guidance manual and identify opportunities to introduce alternative
strategies for the control of vector-borne diseases.
Monitor efficacy and appropriateness of alternatives to DDT,
Firstly, this activity will ensure that information is gathered on
the performance of DDT alternatives, in order to make decisions on
whether to substitute DDT with these alternatives. It will further
provide assistance in the development of standard methods for
governments to document the cost of deploying alternatives, disseminate
these costing methods through national malaria control capacity building
programmes, include training exercises to teach trainers how to educate
others on the use of costing methods, as part of vector-borne disease
control capacity building , and finally, collect information on the cost
increment of alternatives (i.e. the cost margin over and above
the cost of DDT), for purposes of subsidizing the cost increment through
a financial mechanism.
Develop methods for a full economic evaluations of the impact of the
reduction or elimination of DDT use on malaria, including potential
mortality and morbidity.
Communicate with industry to promote further collaboration in the
area of IVM.
Country Needs Assessment
Capacity building needed to promote, utilise and evaluate
alternatives for vector control
This will entail the strengthening of both institutions responsible
for implementing and evaluating integrated disease programs and of
country epidemiological and managerial information systems.
Validation of effectiveness of different vector control
interventions and analysis of their cost-effectiveness
Studies on cost-effectiveness of alternatives to DDT will be
continued and the
applicability and reproducibility of alternative strategies to other
locations, regions, and under different eco-epidemiological situations
will be determined.
Institutional Research Network
Evaluate integrated vector management schemes. Compare their
cost-effectiveness and sustainability with single method approaches
Expeditiously disseminate ongoing results of the WHO Action
Plan to all interested parties. In particular, distribute the scientific
results of alternative strategy implementation and IVM projects
WHO, 1995. Vector control for malaria and other mosquito-borne
diseases. Report of a WHO Study Group, WHO Technical Report Series
857, World Health Organization, Geneva
WHO, 2000. Twenthieth report of the WHO Expert Committee on Malaria, WHO
Technical Report Series 892, World Health Organization, Geneva
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