Research

Spatial and temporal variability of the Glossina palpalis palpalis population in the Mbini focus (Equatorial Guinea)

Jorge Cano¹ , Miguel Angel Descalzo¹ , Nicolas Ndong-Mabale^2,3 , Pedro Ndongo-Asumu³ , Leonardo Bobuakasi² , Jesús N Buatiché² , Sisinio Nzambo-Ondo² , Melchor Ondo-Esono² , Agustin Benito¹ and Jesus Roche¹

¹  National Centre of Tropical Medicine, Instituto de Salud Carlos III, C/Sinesio Delgado 6, 28029, Madrid, Spain

²  National Centre of Endemic Control, Instituto de Salud Carlos III, Bata, Equatorial Guinea, Africa

³  National Sleeping Sickness Control Programme, Ministry of Health and Social Welfare, Bata, Equatorial Guinea, Africa

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International Journal of Health Geographics 2007, 6:36doi:10.1186/1476-072X-6-36

Published:	30 August 2007

Abstract

Background

Human African Trypanosomiasis is a vector-borne parasitic disease. The geographical distribution of the disease is linked to the spatial distribution of the tsetse fly. As part of a control campaign using traps, the spatial and temporal variability is analysed of the glossina populations present in the Mbini sleeping sickness foci (Equatorial Guinea).

Results

A significant drop in the annual mean of the G. p. palpalis apparent density was noted from 2004 to 2005, although seasonal differences were not observed. The apparent density (AD) of G. p. palpalis varies significantly from one biotope to another. The fish dryers turned out to be zones with the greatest vector density, although the AD of G. p. palpalis fell significantly in all locations from 2004 to 2005.

Conclusion

Despite the tsetse fly density being relatively low in fish dryers and jetties, the population working in those zones would be more exposed to infection. The mono-pyramidal traps in the Mbini focus have been proven to be a useful tool to control G. p. palpalis, even though the activity on the banks of the River Wele needs to be intensified. The application of spatial analysis techniques and geographical information systems are very useful tools to discriminate zones with high and low apparent density of G. p. palpalis, probably associated with different potential risk of sleeping sickness transmission.