Incidence events and incidence rates for anti-filarial antibodies and filarial antigenemia before and after mass drug administration (MDA).

Incidence events for each test were defined as positive tests in people who had tested negative in the prior survey and who had never had a positive test in prior years. This analysis is restricted to persons with data available for consecutive years. The pre-MDA-B incidence data are for a 2 year interval (with annual incidence rates shown in parentheses). Other incidence data are for one year intervals. Annual incidence rates for the 2 year period between pre-MDA-A and pre-MDA-B were significantly higher than rates for the two years following the first round of MDA (P<0.001 by chi-square for all comparisons).
Abbreviations: CFA, circulating filarial antigenemia; Bm14, IgG4 antibodies to recombinant filarial antigen Bm14.