Insects are a major cause of human mortality and morbidity, largely as a result of infectious pathogens transmitted by blood-feeding species. Transmission of these vector-borne diseases is governed by complex interactions between the parasite, the vector and people. Rational control of these diseases requires an understanding of the links between various biological, environmental, agricultural and socio-economic factors. NRI's multidisciplinary nature, with its particular expertise in the agricultural, environmental and socio-economic sectors, means that it is increasingly involved in multi-sectoral studies of the impact of vector-borne diseases on rural livelihoods.

NRI's work is mainly focused on the development of sustainable strategies for controlling vectors of infectious diseases affecting communities in developing countries. NRI staff have been involved in research ranging from the use of DNA microsatellites to analyse the feeding behaviour of vectors, to satellite imagery of the earth to map the distribution of diseases.

Research themes:

Environmental information systems. GIS specialists have been using remote sensing and environmental information systems to develop decision support systems to control malaria in Botswana and Mali, and to assess the impact of land use changes on the distribution of onchocerciasis in Ghana. In collaboration with scientists from the Liverpool School of Hygiene, satellite imagery has been used to analyse the environmental determinants of various vector-borne diseases including: Loaiasis, transmitted by horseflies, filariasis, transmitted by mosquitoes and leishmaniasis, transmitted by sandflies.

Odour-baited traps and targets for medical vectors.
Chemists and entomologists have collaborated with European, African and American scientists and institutions to identify the odours used by vectors to locate their hosts. Major vectors studied in this research include various species of Anopheles, Glossina, Triatoma and Simulium which transmit malaria, sleeping sickness, Chagas disease and river blindness respectively. The aim of this research is to provide improved tools for monitoring and controlling these insects

Controlling malaria with insecticide-treated cattle.
Social scientists, GIS specialists, molecular biologists and entomologists have been looking at the feasibility of using insecticide-treated cattle to control malaria. This research is being largely undertaken in Ethiopia, in collaboration with the NGO, FARM Africa, in areas where malaria is transmitted by An. arabiensis which obtains its bloodmeals from cattle and humans. This work builds on previous research concerned with improving the use of insecticide-treated cattle to control tsetse.

Vector control operations.
NRI has been involved in the implementation of large-scale vector control operations. These operations have included aerial spraying operations to control tsetse and blackfly, and odour-baited traps and the use of insecticide-treated cattle to control tsetse.

Staff

Dr Gay Gibson
Dr Steve Torr
Prof. Robert Cheke
Prof. Alan Cork

Projects

Herding for Health: The effects of livestock management practices on the transmission of malaria and trypanosomosis in Ethiopia.
(Funded by the Halley-Stewart Trust/University of Greenwich, 2000-2003; Project Leader Steve Torr (S.Torr@gre.ac.uk); Collaborators FARM Africa)

Controlling malaria and trypanosomiasis with insecticide-treated cattle in Ethiopia
(Funded by DFID KAR, 2001-2002; Project Leader Steve Torr (S.Torr@gre.ac.uk); Collaborators FARM Africa and University of Rome)

Microsatellite mapping of the anthropophily trait in the Anopheles gambiae complex.
(Funded by WHO; Project Leader Gay Gibson (G.Gibson@gre.ac.uk); Collaborator Notre Dame University, USA).

The Use of GIS and Remote Sensing in the Study of Environment Determinants of Vector Borne Disease
(Funded by DFID, 2000-2001: Led by University of Liverpool in collaboration with Ms V. Obsomer (NRI) )

Molecular characterisation of Onchocerca volvulus, its simuliid vectors in Africa and of Mansonella ozzardi in South America using molecular methods.
(1998-2001; Project Leader Robert Cheke (R.A.Cheke@gre.ac.uk), in collaboration with the Natural History Museum).

Development of an odour-baited trapping system for use in control of the vector of chagas disease.
(Funded by EU INCO-DEV, 1998-2001; Project Leader Alan Cork (A.Cork@gre.ac.uk); Collaborators Centro de Investigaciones de Plagas e Insecticideas (Argentina), Departamento de Medicina Tropical del Instituto de Investigaciones en Ciencias de la Salud (IICS; Paraguay ), and Departamento de Química Orgánica Biológica (Spain)).

Publications

Fontán, A., Alzogaray, R., Santo Orihuela, P. Zerba, E., Fernández, D., Camps, F. & Cork, A. (2001) Nitrogenous compounds as attractants of Triatoma infestans (Klug) (Hemiptera: Reduviidae) nymphs. Acta Tropica. (submitted)

Fontán, A., González Audino, P., Martínez , A., Alzogaray, R., Zerba, E., Camps, F. & Cork, A. (2001). Pheromone components produced in copula by vector of chagas disease, Triatoma infestans (Klug) (Hemiptera: Reduviidae): Chemical analysis and behvioral bioassay. Journal of Medical Entomology. (submitted)

Costantini, C., Birkett, M.A., Gibson, G., Ziesmann, J. Sagnon, N'F., Mohammed, H.A., Coluzzi, M. & Pickett, J.A. (2001) Electroantennogram and behavioural responses of the malaria vector Anopheles gambiae to human-specific sweat components, Medical and Veterinary Entomology 15, 1-8.

Morales Hojas, R., Post, R. J., Shelley, A. J., Maia Herzog, M., Coscaron, S. & Cheke, R.A. (2001). Characterisation of Onchocerca volvulus and Mansonella ozzardi (Nematoda: Filarioidea) by nuclear ribosomal DNA and development of a new PCR-based method of detection in skin biopsies International Journal of Parasitology 31, 169-177.

Thomsen, M.C., Obsomer, V., Dunne, M., Conner, S.J. & Molyneux, D.H. (2000). Satellite mapping of Loa loa prevalence in relation to ivermectin use in west and central Africa. Lancet, 356, 1077-1078.

Torr, S.J. & Mangwiro, T.N.C. (2000) Interactions between cattle and biting flies: effects on the feeding rate of tsetse. Medical and Veterinary Entomology, 14, 400-409

Gibson, G. & Torr, S.J. (1999) Visual and olfactory responses of haematophagous Diptera to host stimuli. Medical and Veterinary Entomology, 13, 1-22.

Land, M.F., Gibson, G., Horwood, J. & Zeil, J. (1999) Fundamental differences in the optical structure of the eyes of nocturnal and diurnal mosquitoes. Journal of Comparative Physiology A, 185, 91-103.

Mangwiro, T.N.C., Torr, S.J., Cox, J.R. and Holloway, M.T.P. (1999). The efficacy of various pyrethroid insecticides for use on odour-baited targets to control tsetse. Medical and Veterinary Entomology, 13: 315-323

Millest, A. L., Cheke, R. A. & Greenwood, R. (1999). Distribution of the Simulium metallicum complex in Mexico in relation to selected environmental variables. Medical and Veterinary Entomology 13, 139-149.

Connor, S.J., Thomson, M.C., Flasse, S.P. & Perryman, A.H. (1998). Environmental information systems in malaria risk mapping and epidemic forecasting. Disasters, 22, 39-56.

Costantini, C., Sagnon, N.F., Della-Torre, A., Brady, J., Gibson, G. & Coluzzi, M. (1998) Odor-mediated host preference of West African mosquitoes, with particular reference to malaria vectors. American Journal of Tropical Medicine and Hygiene, 58, 56-63.

McCall, P. J., Cheke, R. A., Wilson, M. D., Post, R. J., Flook, P. K., Mank, R., Sima, A. & Mas, J. (1998). Distribution of the Simulium damnosum complex on Bioko island, Equatorial Guinea, and the potential for onchocerciasis elimination by vector eradication. Medical and Veterinary Entomology 12, 267-275.

Knols, B.G.J, van Loon, J. A. A., Cork, A., Robinson, R. D., Wim, A., Meijerink, J., De Jong, R., & Takken, W. (1997) Behavioural and electrophysiological responses of the female malaria mosquito Anopheles gambiae (Diptera: Culicidae) to Limburger cheese volatiles. Bulletin of Entomological Research. 87, 151-159.

Land, M.F., Gibson, G. & Horwood, J. (1997) Mosquito eye design: conical rhabdoms are matched to wide aperture lenses. Philosophic Transactions of the Royal Society of London, B, 264, 1183-1187.

Thomson, M.C., Connor, S.J., Milligan, P. & Flasse, S.P. (1997). Mapping malaria risk in Africa: What can satellite data contribute? Parasitology Today 13, 313-318.

Cork, A., and Park, K. C. (1996) Identification of electrophysiologically-active compounds for the malaria mosquito, Anopheles gambiae, in human sweat extracts. Medical and Veterinary Entomology, 10, 269-276.

Thomson, M.C., Connor, S.J., Milligan, P.J.M. & Flasse, S.P. (1996). The ecology of malaria - As seen from Earth-observation satellites. Annals of Tropical medicine and Parasitology 90, 243-264.

Cheke, R. A. (1995) Cycles in daily catches of members of the Simulium damnosum species complex. Tropical Medicine and Parasitology 46, 247-252.