The Brugia Impact Survey Sample Builder is designed to help NTD programs implement stop MDA surveys in areas where Brugia is endemic. This is an interim tool that was created in response to the absence of a quality assured antibody diagnostic (Brugia Rapid Test). While the global community waits for a new Brugia test kit to be made available, it is necessary to make Stop MDA decisions based on the prevalence of microfilaraemia in adults.  This tool can assist program managers in designing their Brugia Impact Survey to detect a threshold of <1% Mf in adults.