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Seasonal Variation in the Incidence of Trypanosoma vivax in Glossina palpalis (R.-D.)

Published online by Cambridge University Press:  10 July 2009

F. A. Squire
F. A. Squire
Affiliation:
Entomologist, Department of Agriculture, Sierra Leone.
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Extract

Over 3,000 examples of G. palpalis were age-grouped and dissected for T. vivax over a period of a year. The incidence of infection throughout was highest in Age-group 3 and lowest in Age-group 1. There was a marked seasonal fluctuation, the incidence being highest during the months of heavy rainfall, i.e., August to October, and lowest in the driest.

It has been suggested that the rise in the rate of infection during the rains is merely due to the increasing average age of the fly population, but by the method of age grouping it is shown that this is not the case.

The degree of infection in G. palpalis in Sierra Leone is comparable with that of G. tachinoides in Nigeria.

It is not thought that the seasonal variation in the incidence of infection can be ascribed to changes in the type and abundance of food. The true cause of the fluctuating incidence of infection like the source of infection is unknown.

The failure to recognize seasonal differences in the rate of infection has led to some important practical misconceptions.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 42 , Issue 2 , September 1951 , pp. 371 - 374
Copyright
Copyright © Cambridge University Press 1951

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References

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