Table 1. WNV seroprevalence*.
| Seroprevalence | No. positive/no. tested | Weighted % (95% CI) |
|---|---|---|
| Overall | 34/1,209 | 1.9 (0.8–4.6) |
| Age-specific | ||
| 5–17 y | 4/168 | 6.5 (4.3–9.5) |
| 18–64 y | 25/790 | 1.3 (0.4–4.5)† |
| >65 y | 5/219 | 1.4 (0.4–4.5)‡ |
| Strata-specific | ||
| More human illnesses reported; higher MIR(stratum 1)§¶ | 16/463 | 2.5 (0.6–9.2) |
| Fewer human illnesses reported; varying MIR (stratum 2)# | 7/453 | 1.5 (0.2–4.4) |
| No human illnesses reported; varying MIR (stratum 3)** | 11/293 | 3.3 (0.4–23.9) |
*WNV, West Nile virus; CI, confidence interval; MIR, minimum infection rate. †Significant difference between 5- to 17-year-old and 18- to 64-year-old patients (p<0.02). ‡Significant difference between 5- to 17-year-old and >65-year-old patients (p<0.01). §Reference 9. ¶Stratum 1 included neighborhoods with at least 9 reported human cases, a WNV case rate >4.5/10,000, and mosquito MIR >15/1,000. #Stratum 2 included neighborhoods with at least 1 reported human case, a WNV case rate <4.5/10,000, and varying levels of MIR (0–54/1,000). **Stratum 3 included neighborhoods with no known human cases and varying levels of MIR.