Studies on the Field Epidemiology of Human Onchocerciasis on the Jos Plateau, Nigeria—VII. The Effects of Climatic Factors on the Diurnal Biting Behaviour of Simulium damnosum Theobald (Diptera: Simuliidae)

  • B. E. B. Nwoke
Research Article


The effects of climate on the diurnal biting pattern of Simulium damnosum s.s. were measured at Jos Plateau, Nigeria. Rain in the hours prior to the catch inhibited morning activity by lowering the temperature and light intensity, and raising the humidity. Under shade there were no remarkable fluctuations in the light intensity, and no obvious peaks in activity; in sunny places, activity was bimodal, with a small morning peak and a pronounced afternoon one. The fastest changing climatic factor relative to an increase in the biting activity of flies was light intensity; followed by temperature.

Key Words

Epidemiology onchocerciasis Simulium climatic factors diurnal biting Nigeria 


Les effets du climat sur le mode de morsure diurne du Simulium damnosum s.s ont été mesurés au Plateau de Jos, Nigéria. La pluie aux heures suivant l’attrapage ont inhibe les activités de la matinée avec la baisse de la température et de l’intensité d’illumination et l’accroissement de l’humidité. A l’ombre, on n’a constaté ni de variations importantes de l’intensité d’illumination ni de pointes dans l’activité; au soleil, l’activité était bimodale avec une légère pointe matinale et une pointe prononcée dans l’après-midi. Le facteur climatique le plus variable par rapport à l’accroissement de l’activité de mosure des mouches était l’intensité d’illumination; celle-ci est suivie de la température.


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Copyright information

© ICIPE 1988

Authors and Affiliations

  • B. E. B. Nwoke
    • 1
  1. 1.Medical Entomology & Parasitology Unit, Department of ZoologyUniversity of JosNigeria

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