Chemoecological management of malaria mosquitoes
Rickard Ignell, PhD, Division of Chemical Ecology, Dpt of Plant Protectio...
Chemoecological management of malaria mosquitoes
Rickard Ignell, PhD
Division of Chemical Ecology
Department of Plant Prot...
Malaria is an Anopheles mosquito-borne disease caused by
four species of the parasitic protist genus Plasmodium
Anopheles ...
Global malaria distribution and endemicity
UNICEF, WHO 2005
Global human toll of malaria – malaria cases
Between 350 million and 500 million episodes of clinical malaria occur each y...
Global human toll of malaria - deaths
1-1.5 million people die each year, predominantly in sub-Saharan Africa
Worldmapper ...
In sub-Saharan Africa, malaria is one of the major causes of death of
children under the age five, accounting for nearly 1...
Global human toll of malaria - poverty
Worldmapper project
“Malaria is both a root cause and a consequence of poverty. Mal...
Global human toll of malaria – gross domestic product
Worldmapper project
Malaria can decrease GDP by 1.3% in countries wi...
Tabachnick, W. J. J Exp Biol 2010;213:946-954
The vector-borne disease episystem illustrating interactions between
selecte...
In Africa, malaria is predominantly a rural disease where agriculture
forms the backbone of the economy
0 20 40 60 80 100
0 1 2 3 4
Flooding rice irrigation
Non-flooding rice irrigation
Wet savannah
Sugarcane
Dry savannah
Vari...
Changes in agro-ecosystems and crop production systems may affect
malaria transmission.
Kebede et al (2005) Am J Trop Med ...
Indoor residual spraying (IRS)
Insecticide treated mosquito nets (ITNs)
Vector control of malaria is the primary public he...
Griffin et al (2010) Plos Medicine 7:e1000324
Interventions have resulted in major reductions in malaria transmission,
and...
0 10 20 30 40 50
Permethrin
Deltamethrin
Lambda-cyhalothrin
Bendiocarb
DDT
Malathion
Insecticide resistance (%)
Cuamba et ...
Focuses on “…exploitation of the behavior and general
ecology of the mosquitoes to reduce contact with human
hosts…”
What ...
Chemoecological management of malaria mosquitoes
Curtesy of Prof. Laurence Zwiebel
Chemical cues play a significant role for mosquito behavior
Oviposition attractants Larval attractants
Host attractants
Main aim: identification of novel attractants that may be used...
Multi-pronged, comparative, approach
Odor collection
Physiological analysis
Molecular analysis
Behavioral analysis
What we have achieved so far
• Improved efficacy of existing ’general’ mosquito lure
• Novel identicatication of attractan...
What we have achieved so far
SLU
Richard Hopkins
Teun Dekker
Sharon Hill
Bonaventure Aman
Marcelo Lorenzo
Majid Ghaninia
Siju Purayil
Shahid Majeed
Ack...
Upcoming SlideShare
Loading in …5
×

Chemoecological Management of Malaria Mosquitoes

671 views

Published on

This study was presented during the conference “Production and Carbon Dynamics in Sustainable Agricultural and Forest Systems in Africa” held in September, 2010.

Published in: Health & Medicine, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
671
On SlideShare
0
From Embeds
0
Number of Embeds
6
Actions
Shares
0
Downloads
9
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Chemoecological Management of Malaria Mosquitoes

  1. 1. Chemoecological management of malaria mosquitoes Rickard Ignell, PhD, Division of Chemical Ecology, Dpt of Plant Protection Biology, Swedish University of Agricultural Sciences (SLU) ABSTRACT Globally, malaria annually affects about 300 million people and causes about one million deaths, mostly among children in sub-Saharan Africa. In this region, the mosquito, Anopheles gambiae, is considered the most efficient vector of malaria. Due to its socio-economical importance, several countries are implementing vector control activities in an attempt to curtail the malaria epidemic. Vector control interventions, combining insecticide-treated bed nets (ITNs) and indoor residual spraying (IRS) have suppressed An. gambiae populations in some malaria-endemic areas in sub-Saharan Africa. However, in other areas, such as the western part of Kenya, while the impact of ITNs and IRS on An. gambiae has been dramatic, these intervention methods have had very little impact on the populations of An. arabiensis. There is growing evidence that the void created by the low populations of An. gambiae is being filled by An. arabiensis since current malaria infections in these areas are caused by the latter rather than the former species. The potential for a similar pattern of malaria infection, with An. arabiensis as the principal malaria vector, in other parts of Africa where the two malaria vectors co-occur after intervention with ITNs and IRS is very high. A call has recently been issued for worldwide, integrated efforts to prevent further deterioration of the malaria situation. One such effort focuses on the exploitation of the chemical ecology of Anopheles mosquitoes to reduce the interactions with humans. In a recently initiated study we at SLU are trying to develop a low-input bait technology for trapping and repelling An. arabiensis.
  2. 2. Chemoecological management of malaria mosquitoes Rickard Ignell, PhD Division of Chemical Ecology Department of Plant Protection Biology Swedish University of Agricultural Sciences (SLU) Production and Carbon Dynamics in Sustainable Agriculture and Forest Systems in Africa Policy, Economics and Incentives Stockholm September 2010
  3. 3. Malaria is an Anopheles mosquito-borne disease caused by four species of the parasitic protist genus Plasmodium Anopheles gambiae Plasmodium falciparum attacking human red blood cells
  4. 4. Global malaria distribution and endemicity UNICEF, WHO 2005
  5. 5. Global human toll of malaria – malaria cases Between 350 million and 500 million episodes of clinical malaria occur each year Worldmapper project
  6. 6. Global human toll of malaria - deaths 1-1.5 million people die each year, predominantly in sub-Saharan Africa Worldmapper project
  7. 7. In sub-Saharan Africa, malaria is one of the major causes of death of children under the age five, accounting for nearly 1 death in 5 UNICEF, WHO 2005 Distribution of deaths among children under age five by cause, global and sub-Saharan Africa, 2000–2003
  8. 8. Global human toll of malaria - poverty Worldmapper project “Malaria is both a root cause and a consequence of poverty. Malaria is most intractable for the poorest countries and communities in the world that face a vicious cycle of poverty and ill health”. The Earth Institute
  9. 9. Global human toll of malaria – gross domestic product Worldmapper project Malaria can decrease GDP by 1.3% in countries with high disease rates
  10. 10. Tabachnick, W. J. J Exp Biol 2010;213:946-954 The vector-borne disease episystem illustrating interactions between selected environmental factors with effects on the vector--pathogen-- host epidemiologic cycle
  11. 11. In Africa, malaria is predominantly a rural disease where agriculture forms the backbone of the economy
  12. 12. 0 20 40 60 80 100 0 1 2 3 4 Flooding rice irrigation Non-flooding rice irrigation Wet savannah Sugarcane Dry savannah Various agro-ecosystems and crop production systems have an impact on mosquito productivity, and malaria transmission intensity. % of mosquitoes Plasmodium sporozite rate (%) Mboera et al (2010) Geospatial Health 4(2), 2010, pp. 167-178 Mvomero district, Tanzania
  13. 13. Changes in agro-ecosystems and crop production systems may affect malaria transmission. Kebede et al (2005) Am J Trop Med Hyg 73(4): 676–680 Bure Malaria incidence rate/10.000 person-years Maizecultivationintensity 0 100 200 300 High Medium Low
  14. 14. Indoor residual spraying (IRS) Insecticide treated mosquito nets (ITNs) Vector control of malaria is the primary public health intervention for reducing malaria transmission at the community level Other methods
  15. 15. Griffin et al (2010) Plos Medicine 7:e1000324 Interventions have resulted in major reductions in malaria transmission, and provided an efficient control of endophilic Anopheles mosquitoes
  16. 16. 0 10 20 30 40 50 Permethrin Deltamethrin Lambda-cyhalothrin Bendiocarb DDT Malathion Insecticide resistance (%) Cuamba et al (2010) Plos ONE 5: e11010 High levels of insecticide resistance in Anopheles mosquitoes has been observed in several regions of Africa Chokwe District, Mozambique
  17. 17. Focuses on “…exploitation of the behavior and general ecology of the mosquitoes to reduce contact with human hosts…” What it all comes down to: C = Vectorial capacity, the number of infective bites received daily by a single host; m = Density of vectors in relation to density of hosts; a = Proportion of vectors feeding on a host divided by the length of gonotrophic cycle in days; V = Vector competence; P = Daily survival of vectors; n = Extrinsic incubation period ma2VPn -logeP C = WHO’s call for worldwide integrated efforts to prevent further deterioration of the malaria situation
  18. 18. Chemoecological management of malaria mosquitoes
  19. 19. Curtesy of Prof. Laurence Zwiebel Chemical cues play a significant role for mosquito behavior
  20. 20. Oviposition attractants Larval attractants Host attractants Main aim: identification of novel attractants that may be used in integrated vector management of Anopheles mosquitoes
  21. 21. Multi-pronged, comparative, approach Odor collection Physiological analysis Molecular analysis Behavioral analysis
  22. 22. What we have achieved so far • Improved efficacy of existing ’general’ mosquito lure • Novel identicatication of attractants for Culex quinquefasciatus, the major vector of human filiariasis in Africa • Identification of the first oviposition attractant of Anopheles mosquitoes
  23. 23. What we have achieved so far
  24. 24. SLU Richard Hopkins Teun Dekker Sharon Hill Bonaventure Aman Marcelo Lorenzo Majid Ghaninia Siju Purayil Shahid Majeed Acknowledgement: Carl Tryggers Stiftelse för Vetenskaplig Forskning

×