Prevalence of circulating filarial antigens (A) and microfilaraemia (B) in the rural study communities in Tanga District during surveys 1 and 7–9. Data are from individuals aged ≥10 years from two hamlets of Kirare (Mtambuuni, Mashine), one hamlet of Kiomoni (Mabavu) and one hamlet of Kisimatui (Majengo). Bar = prevalence in Kirare at the pre-MDA survey in 2004; Orange line = prevalence in Kirare in survey 7–9; Green line = prevalence in Kiomoni in survey 7–9; Blue line = prevalence in Kisimatui in survey 7–9. In the pre-MDA survey all individuals were examined for mf, and volunteers from mosquito collection houses only were examined for CFA by ELISA. In surveys 7–9 all individuals were first examined for CFA with ICT cards, and those positive were examined for mf. Vertical stippled lines indicate rounds of MDA.