Impact of Mass Drug Administration of Ivermectin, Diethylcarbamazine, Albendazole, and Azithromycin on Lymphatic Filariasis, Scabies, and Yaws in West New Britain Province, Papua New Guinea

West New Britain province (WNBP), Papua New Guinea, is the first to combine ivermectin, diethylcarbamazine, albendazole (IDA), and azithromycin for mass drug administration (MDA). We describe the impact of four-drug MDA on lymphatic filariasis (LF), scabies, and yaws through active and passive surveillance. At baseline, 43 villages were surveyed following selection using model-based geostatistics. Repeat surveys were conducted in 10 high burden villages, one year after MDA. Circulating filarial antigen (CFA) and microfilaria (Mf) microscopy detected LF infections; skin examinations identified yaws and scabies. Electronic data from 27 health centers (HCs) compared monthly attendances in the six months before/after MDA. Pre-MDA, 151/3,552 (4.3%) participants tested CFA-positive, with 49 (1.4%) Mf-positive. Scabies was identified in 489/3,552 (13.8%) and yaws-like lesions in 130/3,552 (3.6%). In the 10 villages surveyed pre- and post-MDA, CFA positivity decreased by 49% (RR 0.51; CI 0.38, 0.70; p<0.0001; 11.5% to 5.9%), Mf prevalence 85% (RR 0.15; CI 0.07, 0.30; p<0.001; 4.7% to 0.9%), scabies 78% (RR 0.22; CI 0.14 - 0.33; p<0.0001; 11.1% to 2.4%) and yaws 31% (RR 0.69; CI 0.41 - 1.14; p=0.15; 3.8% to 2.5%). Mean (SEM) monthly HC attendances for yaws-like lesions decreased from 27.4 ± 0.9 to 15.5 ± 1.6 (p<0.0001) and for other skin diseases from 95.6 ± 3.4 to 72.9 ± 7.7 (p<0.0001), with no significant change in total non-skin disease attendances (728.8 ± 30.9 to 796.8 ± 44.4, p=0.178). MDA with IDA and azithromycin reduced LF and other skin infections burden in WNBP, demonstrating the effectiveness of four-drug MDA and the potential for using active and passive surveillance to monitor impact.