Table 4. Summary of sampling and recruitment for community survey; and prevalence of circulating filarial antigen (CFA) for selected villages, American Samoa 2016.
| Village | Total number of residents1 | Total number of households | Target number of households | Number of households sampled (% of target) | Target population aged ≥8 years | Number recruited (% of target) |
Number FTS-positive | Number Microfilaria positive | Crude CFA prevalence (%) | Adjusted CFA prevalence (95% CI)2 |
|---|---|---|---|---|---|---|---|---|---|---|
| Afono | 524 | 75 | 22 | 21 (95.5) | 69 | 71 (82.3) | 3 | 1 | 4.2 | 4.0 (1.7–9.3) |
| Alao | 495 | 71 | 20 | 12 (60) | 65 | 44 (54) | 0 | - | 0 | - |
| Amaua | 96 | 14 | 4 | 5 (125) | 13 | 19 (120.2) | 1 | - | 5.3 | 4.9 (1.4–16.3) |
| Amouli | 920 | 131 | 38 | 33 (86.8) | 121 | 111 (73.3) | 2 | - | 1.8 | 2.7 (1–7) |
| Asili | 224 | 32 | 9 | 9 (100) | 30 | 28 (75.9) | 4 | - | 14.3 | 19.6 (9.7–35.6) |
| Auma | 254 | 36 | 10 | 9 (90) | 33 | 39 (93.2) | 2 | - | 5.1 | 8.3 (3.2–19.7) |
| Aumi | 186 | 27 | 8 | 6 (75) | 25 | 23 (75.1) | 0 | - | 0 | - |
| Fagamalo | 47 | 7 | 2 | 3 (150) | 6 | 13 (168) | 4 | 3 | 30.8 | 47.1 (16.9–79.6) |
| Faganeanea | 150 | 21 | 6 | 5 (83.3) | 20 | 23 (93.1) | 0 | - | 0 | - |
| Fagatogo | 1737 | 248 | 72 | 55 (76.4) | 229 | 212 (74.1) | 5 | - | 2.4 | 2.7 (1.4–5.2) |
| Fatumafuti | 113 | 16 | 5 | 3 (60) | 15 | 5 (26.9) | 1 | - | 20.0 | 44.8 (10–85.5) |
| Ili'ili3 | 3195 | 456 | 132 | 87 (65.9) | 421 | 308 (58.5) | 15 | 3 | 4.9 | 4.9 (3.2–7.5) |
| Lauli'i | 892 | 127 | 37 | 27 (73) | 118 | 104 (70.8) | 1 | - | 1.0 | 1.1 (0.3–4) |
| Leloaloa | 448 | 64 | 18 | 15 (83.3) | 59 | 40 (54.2) | 7 | 2 | 17.9 | 25.8 (16.1–38.4) |
| Malaeimi | 1182 | 169 | 49 | 36 (73.5) | 156 | 120 (61.6) | 5 | 1 | 4.2 | 10.9 (5–22.2) |
| Malaeloa/Aitulagi | 698 | 100 | 29 | 20 (69) | 92 | 90 (78.3) | 4 | 2 | 4.4 | 8.1 (3.3–18.6) |
| Masausi | 164 | 23 | 7 | 7 (100) | 22 | 24 (88.9) | 0 | - | 0 | - |
| Nua | 141 | 20 | 6 | 3 (50) | 19 | 17 (73.2) | 0 | - | 0 | - |
| Pago Pago4 | 1828 | 261 | 75 | 62 (82.7) | 241 | 228 (75.7) | 4 | 1 | 1.8 | 2.3 (1.2–4.5) |
| Pava'ia'i | 2450 | 350 | 101 | 73 (72.3) | 323 | 255 (63.2) | 3 | - | 1.2 | 2.5 (0.8–7.5) |
| Satala-Anua-Atuu | 674 | 96 | 28 | 22 (78.6) | 89 | 81 (73) | 7 | 2 | 8.8 | 9.0 (4.3–17.7) |
| Se'etaga | 299 | 43 | 12 | 13 (108.3) | 39 | 49 (99.5) | 2 | - | 4.1 | 3.4 (1.3–8.5) |
| Tafuna5 | 2000 | 286 | 82 | 56 (68.3) | 263 | 187 (56.8) | 5 | 1 | 2.7 | 3.3 (1.4–7.6) |
| Taputimu | 841 | 120 | 35 | 29 (82.9) | 111 | 88 (63.5) | 0 | - | 0.0 | - |
| Tula | 405 | 58 | 17 | 14 (82.4) | 53 | 52 (78) | 4 | - | 7.7 | 14.5 (5.9–31.5) |
| Utumea West | 53 | 8 | 2 | 3 (150) | 7 | 12 (137.5) | 1 | - | 8.3 | 12.7 (3.2–39.4) |
| Vaitogi | 1959 | 280 | 81 | 64 (79) | 258 | 212 (65.7) | 18 | 6 | 8.5 | 11.8 (7.9–17.4) |
| Vatia | 640 | 91 | 26 | 19 (73.1) | 84 | 52 (49.3) | 4 | - | 7.8 | 21.8 (9.8–41.6) |
| Total | 22601 | 3230 | 933 | 711 (76.2) | 2981 | 2507 (84.1) | 102 | 22 | 4.1 | 6.2 (4.5–8.6) |
1 Population estimates based on American Samoa 2014 Statistical Yearbook (American Samoa Department of Commerce). 80% of the population is estimated to be aged ≥8 years.
2 Adjusted for survey design, and post-stratified for age and sex using ‘svyset’ in Stata13.
3 Villages were split into two segments for the selection of PSUs. Both segments of both villages were selected. Data presented here are pooled for both segments for each of the villages.
4 One of two segments of Pago Pago was selected; number of residents shown here is half of the total population of Pago Pago.
5 One of four segments of Tafuna was selected; number of residents shown here is quarter of the total population of Tafuna.