Mass drug administration (MDA) programs have dramatically reduced lymphatic filariasis (LF) incidence in many areas around the globe, including Bangladesh. Post-treatment surveillance activities as recommended by WHO include repeated transmission assessment surveys (TAS) among children and ongoing surveillance to detect new foci of transmission and collect data on infection trends in the general population. The contribution of molecular xenomonitoring (MX, or detection of filarial DNA in mosquitoes) to confirm the interruption of transmission during the post-treatment surveillance phase has not been well defined. There is also a need to better understand the relationship between the prevalence of W. bancrofti DNA in mosquitoes and infection in humans.