Estimation of the survival rate and oviposition cycle of field populations of malaria vectors in Kenya.
Abstract
Eight populations of malaria vectors in Kenya were sampled over 3 years. Each population was sampled for up to one month. Relative density, parous rate and pre-gravid rate were measured. Each population consisted of a single species of Anopheles gambiae, A. arabiensis, A. merus or A. funestus. The coherence of the data and the mean duration of the oviposition cycle were determined by cross-correlation analysis. Four of the 8 data sets were considered suitable for analysis. The mean survival rate per oviposition cycle was determined by ordinary least squares linear regression with zero intercept. The oviposition cycle ranged from 2 to 4 days. The survival rates per oviposition cycle were similar for A. gambiae and A. merus. The survival rate of A. arabiensis was lower. The expected infective life was longest for A. gambiae in the dry season, when the oviposition cycle was longest. The implications of these results for malaria epidemiology are discussed.