Figure 2.

Depletion of Wolbachia from Onchocerca volvulus larvae reduces the number of larvae that develop into the infective stage in the Simulium vector. The proportion of larvae at each stage was calculated by dividing the number of larvae (stage L1+L2; L3) by the total larvae collected from the captured blackflies after they had fed on the doxycycline (n = 7) or placebo (n = 5) treated volunteers. The proportion of L1+L2 larvae in flies that had fed on doxycycline treated individuals (black bars) was higher beginning at 3 months post-treatment compared to placebo. The proportion of L3 larvae in flies that had fed on doxycycline treated volunteers (white bars) was lower than that in the placebo volunteers at 3, 4 and 5 months post-treatment. Proportions are given as percentages of median larval recovery. 100% corresponded to the total number of larvae recovered at each indicated time.