Rickettsia-like organisms, puparial temperature and susceptibility to trypanosome infection in Glossina morsitans.

Maintaining the puparial stage of successive generations of a population of tsetse 3 degrees C lower than normal reduced the numbers of rickettsia-like organisms (RLO) carried by emerging flies. The susceptibility of these flies to midgut infection with Trypanosoma congolense was also significantly reduced compared with control flies held at normal temperature. These results support the view that the relationship between RLO and susceptibility is quantitative-teneral flies with heavier RLO infections being more susceptible to trypanosome infection.