This document discusses vector control research needs for neglected tropical diseases. It identifies several challenges with current vector control efforts, including lack of resources, delays in implementation, and lack of routine surveillance. It also discusses knowledge gaps around dengue virus transmission and the impact of vector interventions. Key research areas are identified such as measuring entomological risk, assessing the epidemiological impact of control, and monitoring insecticide resistance. The document emphasizes the need for integrated vector management approaches and evaluating current tools and strategies to better understand their disease impact.

1. Vector control research needs for NTDs
Dr Raman Velayudhan,
Coordinator,
Vector Ecology and Management, NTD

2. Challenges of Vector Control
 Lack of resources
 Very often used as a last resort
Equipment's and plans are developed after the outbreak is
underway
A delay of over a week makes control ineffective
 Decentralization of health services
Trained staff
Procurement of appropriate interventions
Lack of routine vector surveillance
 Urban vector control
Delivery/Responsibility
Community involvement
Often blamed for failure

3. Aedes aegypti and Aedes albopictus

4. Knowledge & Research Gaps for Dengue Vector
Control
• Why is disease burden increasing?
Unsuccessful programs: Lack of resources, lack of political will or
ineffective implementation
Also responsible: Deficiencies in understanding virus transmission,
methods for assessing & responding to risk & failure to effectively use
surveillance data for control decisions
Knowledge & research gaps:
• Entomological measures of risk
• Epidemiologic impact of vector interventions
• Insecticide resistance: monitor & manage
• Spatial scales that characterize transmission
• Dynamic responses to control
• Research design for VC

5. Urban, semi-urban and rural movement
• Human movement –
critical and understudied
component in
transmission
• Facilitate identification of
hot spots, prompt
response and suppress
outbreaks
• Surveillance, intervention
and prevention
• Points of entry needs to
be monitored for vectors
under IHR (2005)

6. A Critical Assessment of Vector Control
for Dengue Prevention
NL Achee, F Gould, TA Perkins, RC Reiner, Jr., AC
Morrison, S Richie, DJ Gubler, and TW Scott

7. HAT and vector
• Vector borne disease, transmitted by glossina genus (tsetse fly)
• Main species involved:
• Gambiense HAT: G. palpalis, G. fuscipes
• Rhodesiense HAT: G. morsitans, G. fuscipes, G. pallidipes, G. Swynnetoni

8. HAT vector control
• Multiple vector control methods available, to be adapted to different
epidemiological settings
Ground spraying
Aerial spraying
Sterile insects release
Mobile baits
Natural baits
Protective fences
Artificial baits
Repellents

9. Rhodesiense HAT and vector control
• Rhodesiense HAT is a zoonotic disease where wildlife and
domestic animals are the main reservoirs. Vector control
and treatment of infected animals when possible are key
elements for controlling the disease.
• Vector control has successfully used in some Rhodesian
HAT foci. Successes were achieved through large-scale
operations, expensive and requiring strong vector control
departments
• Current vector control tools are highly variable in
characteristics and quality (Fabrics, colors, insecticide
loading and release,…). Target product profiles of these
tools tailored to different environments are needed.
• It is needed to improve the evidence-based knowledge for
countries to make decisions on which tools to use in
different settings, and how to use them most effectively.

10. Elimination of intra-domiciliary vectorial transmission of Chagas disease
in Latin America (2020)
Control of vectorial
transmission by August 2015
0
5,000,000
10,000,000
15,000,000
20,000,000
25,000,000
30,000,000
WHO1960
WHO1976
WHO1981
PAHO1984
Walsh1984
WHO1985
WHO1990
WHO1991
WHO1992
PAHO1994
Schmunis1999
Schmunis1999
Schmunis2000
WorlBank/DCPP2006
PAHO/WHO2006
WHO2010
WHO2013
WHO2014
Series1
Latin
American
Initiatives
Non endemic coutries
Initiative
• 3 hot control areas remaining: Gran Chaco, El Salvador/Guatemala & Amazon basin

12. Network to monitor triatomine bug resistance to
insecticides – REMOT

13. What tools/approaches are available for tackling exophilic
and exophagic sandflies?
1. Treating other main sources of bloodmeals with
systemic insecticides (endectocides), such as fipronil
and imidacloprid.
2. Exploiting sugar-feeding behaviour of vectors to
develop attractive toxic sugar baits (ATSBs)
3. Environmental Control
4. Developing insecticide-impregnated or repellent-
impregnated products to be used by specific
communities.
5. Pheromones?
6. Genetic Control? (e.g. SIT: sterile insect technique)

14. Integrated Vector Management
A rational decision-making process for
optimal use of resources for vector control
How do we operationalize IVM?

15. Framework for planning & implementation
2. Selection of
vector control
methods
3. Needs &
resources
4. Implementation
5. Monitoring
& evaluation
Disease situation
• Integrated surveillance
Vector, cases, lab
• Vector assessment
• Epidemiological assessment
• Stratification
• Local determinants of disease
Diseases specific
reporting needs

16. Conclusion
 Current tools & strategies have not been evaluated
adequately for disease impact (epidemiologic outcomes)
 There is current research on new tools/strategies, but little
support for improving delivery & coverage of vector control
 The biggest gap in current vector control for is how much
coverage is necessary for disease reduction goals
 General consensus is that 1 approach will not solve the
problem by itself, we need to use a combination of
approaches
 Vector control & vaccines: How exactly should this be done?
 Urban health and delivery of services needs to be addressed
 Sustained vector control interventions needs to be promoted