Analysis of survival data for Simulium damnosum using the regression method.

The survival data (under laboratory conditions) for blackfly (Simulium damnosum) are analysed using Cox's proportional hazard model, and an accelerated life model assuming a Weibull baseline survival function. The results show that allowing for the numerical density of microfilariae uptake is important as a covariate term in the Cox's model. High values of the covariate significantly reduce the chances of survival of the fly. The appropriate explicit expression for the survival function obtained can explain the low proportion of infective flies observed in the field.