The effects of Plasmodium cynomolgi on the longevity of Anopheles dirus were examined. The mortality rates of infected and non-infected groups surviving to the beginning of post-feeding periods 0-3, 4-8 and 31-40 days were not significantly different. However, there was a significant difference in the mortality rates between the 2 groups for periods 9-13, 14-20 and 21-30 days. A comparison of the cumulative mortality rates further illustrates that the mortality rates of the 2 groups were nearly the same until about day 10, when the mortality rate of the infected group was increased greatly. Furthermore, dissection of infected mosquitoes revealed excessive bacteria and deterioration of the midgut and salivary glands, especially for days 9-20. The mortality rates for both the infected and non-infected groups were higher for days 0-3 than for days 4-8, a possible post-blood feeding response.
