Twenty-nine strains of Aedes aegypti from East Africa were tested to determine susceptibility to Brugia pahangi. Susceptibility (complete development of at least 1 microfilaria to an L3 stage larva) varied from 0–59%, with 17 strains showing some susceptible individuals. Each strain was tested along with a control strain; in 64 replicates, the latter showed 94.5 ± 7.4% susceptibility. High susceptibility was correlated with increased mortality and inability to fly following infection. When strains were classified by habitat of origin, it was found that sylvan strains were most susceptible, domestic strains were refractory and peridomestic strains were intermediate.