Table 3.
Univariate analysis of residence and mobility/travel risk factors affecting antigen and antibody positivity
| Factor | Level | Ag | Bm14 Ab | Wb123 Ab | Any Ab | ||||
|---|---|---|---|---|---|---|---|---|---|
| % positive (n) | OR (95% CI) | % positive (n) | OR (95% CI) | % positive (n) | OR (95% CI) | % positive (n) | OR (95% CI) | ||
| Years lived in AS | < 9 | 2.91 (103) | Ref | 8.74 (103) | Ref | 12.62 (103) | Ref | 15.53 (103) | Ref |
| 9–14 | 2.25 (89) | 0.77 (0.13–4.69) | 19.10 (89) | 2.47 (1.04–5.85)*** | 17.98 (89) | 1.52 (0.69–3.36) | 25.84 (89) | 1.89 (0.93–3.87)** | |
| > 14 | 1.54 (456) | 0.52 (0.13–2.04) | 10.82 (453) | 1.27 (0.60–2.67) | 9.49 (453) | 0.73 (0.37–1.41) | 15.67 (453) | 1.01 (0.56–1.82) | |
| Ever been outside AS | No | 2.78 (72) | 6.94 (72) | 9.72 (72) | 11.11 (72) | ||||
| Yes | 1.72 (577) | 0.62 (0.13–2.87) | 12.37 (574) | 1.89 (0.74–4.85)* | 11.50 (574) | 1.21 (0.53–2.74) | 17.94 (574) | 1.75 (0.81–3.76)* | |
| Travel to Samoaa | No | 1.86 (431) | 12.12 (429) | 11.66 (429) | 17.72 (429) | ||||
| Yes | 1.83 (218) | 0.99 (0.29–3.32) | 11.06 (217) | 0.90 (0.54–1.51) | 10.60 (217) | 0.90 (0.53–1.52) | 16.13 (217) | 0.89 (0.58–1.38) | |
| Visitor from Samoaa | No | 1.83 (383) | 12.34 (381) | 11.55 (381) | 17.59 (381) | ||||
| Yes | 1.90 (263) | 1.04 (0.33–3.32) | 11.07 (262) | 0.88 (0.54–1.45) | 11.07 (262) | 0.95 (0.58–1.57) | 16.79 (262) | 0.95 (0.62–1.44) | |
| Travel to endemic areaa | No | 1.90 (421) | 12.41 (419) | 11.69 (419) | 17.90 (419) | ||||
| Yes | 1.76 (227) | 0.93 (0.28–3.11) | 10.62 (226) | 0.84 (0.50–1.40) | 10.18 (226) | 0.86 (0.51–1.45) | 15.49 (226) | 0.84 (0.54–1.30) | |
| Travel to non-endemic areaa | No | 2.05 (584) | # | 12.18 (583) | 11.66 (583) | 17.50 (583) | |||
| Yes | 0.00 (64) | na | 8.06 (62) | 0.63 (0.25–1.63) | 6.45 (62) | 0.52 (0.18–1.48) | 12.90 (62) | 0.70 (0.32–1.51) | |
*P < 0.2, **P < 0.1, ***P < 0.05, ****P < 0.01, # not significant (Fisher’s exact test)
aIn last 12 months
Abbreviations: Ag: antigen (ICT and/or Og4C3); AS, American Samoa; n, no. positive; N, no. tested; na, not available (zero cases); ref, reference category