Table 5.
Preschool (PSAC) and school (SAC) aged pre-treatment prevalence % (95%CI) and relative reductions % (Wald test: Z-statistic, p-value) for hookworm infection in 20 counties in Kenya.
| County | Year 1 | Year 3 | Year 5 | Year 6 | Relative Reduction (Year 1 – Year 6) RR% (Wald test, p-value) | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| PSAC | SAC | PSAC | SAC | PSAC | SAC | PSAC | SAC | PSAC | SAC | |
| Bomet | 0 | 0.2 (0–0.6) | 0 | 0.1 (0–0.6) | 0 | 0.1 (0–0.6) | 0 | 0 | 0 | 100 (Z = −9.42, p < 0.001)* |
| Bungoma | 45.2 (34.8–58.5) | 44.0 (37.0–52.3) | 1.0 (0.1–8.0) | 1.7 (0.7–4.4) | 0.8 (0.1–5.0) | 0.8 (0.4–1.7) | 1.7 (0.3–11.3) | 0 | 96.2 (Z = −3.52, p < 0.001)* | 100 (Z = −9.29, p < 0.001)* |
| Busia | 16.1 (10.5–24.6) | 21.0 (16.7–26.4) | 4.5 (2.1–9.9) | 3.0 (1.8–5.0) | 1.2 (0.4–3.4) | 3.0 (2.0–4.4) | 0 | 1.2 (0.2–8.6) | 100 (Z = −8.43, p < 0.001)* | 94.2 (Z = −3.05, p = 0.002)* |
| Garissa | -ns | -ns | -ns | -ns | -ns | -ns | 0 | 0 | -ns | -ns |
| Homa Bay | 8.5 (5.1–14.2) | 15.8 (12.9–19.3) | 6.2 (3.6–10.6) | 5.1 (3.4–7.7) | 1.7 (0.5–5.5) | 2.7 (1.4–5.2) | 0 | 5.7 (2.8–11.7) | 100 (Z = −9.45, p < 0.001)* | 63.8 (Z = −2.90, p = 0.004)* |
| Kakamega | 27.1 (20.0–36.8) | 22.2 (16.7–29.4) | 0 | 0.9 (0.4–1.7) | 2.0 (0.7–6.2) | 0.3 (0.1–0.8) | 2.4 (0.3–19.2) | 2.7 (2.1–3.4) | 91.0 (Z = −2.49, p = 0.013)* | 88.0 (Z = −12.12, p < 0.001)* |
| Kericho | 5.6 (2.2–14.0) | 5.9 (3.1–11.1) | 1.0 (0.2–6.5) | 0 | 0 | 0.2 (0–0.7) | 0 | 0.4 (0.1–3.0) | 100 (Z = −6.15, p < 0.001)* | 93.1 (Z = −3.08, p = 0.002)* |
| Kilifi | 28.0 (18.6–42.1) | 31.2 (29.3–33.1) | 0 | 3.2 (2.2–4.7) | 0 | 1.1 (0.9–1.3) | 0 | 0.7 (0.2–2.8) | 100 (Z = −6.12, p < 0.001)* | 97.8 (Z = −5.52, p < 0.001)* |
| Kisii | 9.9 (4.5–21.9) | 11.0 (7.0–17.3) | 0 | 1.5 (0.9–2.6) | 0.9 (0.1–6.1) | 0.9 (0.5–1.4) | 1.4 (0.2–9.2) | 0.2 (0–1.7) | 85.4 (Z = −2.26, p = 0.024)* | 98.0 (Z = −3.83, p < 0.001)* |
| Kisumu | 11.0 (5.3–23.2) | 7.9 (5.0–12.5) | 1.1 (0.2–7.2) | 0.3 (0.1–1.3) | 0 | 0.7 (0.3–1.8) | 0 | 0.2 (0–1.4) | 100 (Z = −5.81, p < 0.001)* | 97.6 (Z = −4.11, p < 0.001)* |
| Kitui | -ns | -ns | -ns | -ns | -ns | -ns | 0 | 0.4 (0.1–1.3) | -ns | -ns |
| Kwale | 20.4 (11.6–36.0) | 25.8 (18.8–35.4) | 5.8 (2.9–11.4) | 13.8 (8.7–22.1) | 3.7 (2.5–5.6) | 3.0 (2.0–4.6) | 0 | 3.0 (1.4–6.4) | 100 (Z = −5.49, p < 0.001)* | 88.5 (Z = −5.95, p < 0.001)* |
| Makueni | -ns | -ns | -ns | -ns | -ns | -ns | 0 | 0.6 (0.2–2.1) | -ns | -ns |
| Migori | 16.5 (10.1–27.2) | 20.8 (16.5–26.0) | 0 | 0.8 (0.4–1.5) | 0 | 0.4 (0.2–1.1) | 1.5 (0.2–10.7) | 0.6 (0.2–2.3) | 90.8 (Z = −2.39, p = 0.017)* | 96.9 (Z = −5.23, p < 0.001)* |
| Mombasa | 4.9 (0.5–52.0) | 7.9 (1.8–35.3) | 0 | 0.7 (0.3–1.7) | 0 | 0 | 0 | 0.9 (0.1–6.0) | 100 (Z = −2.50, p = 0.012)* | 88.9 (Z = −1.95, p = 0.052) |
| Narok | 4.0 (1.6–10.0) | 5.3 (2.3–11.8) | 0 | 0.9 (0.5–1.7) | 1.2 (0.1–10.3) | 1.3 (0.6–2.7) | 0 | 0 | 100 (Z = −6.96, p < 0.001)* | 100 (Z = −7.15, p < 0.001)* |
| Nyamira | 5.0 (1.3–18.7) | 1.6 (0.6–4.1) | 0 | 0.4 (0.2–0.9) | 0 | 0.1 (0–0.7) | 0 | 0.5 (0.1–3.3) | 100 (Z = −4.44, p < 0.001)* | 70.8 (Z = −1.22, p = 0.224) |
| T. Taveta | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Vihiga | 17.6 (10.2–30.6) | 15.7 (8.8–27.9) | 0 | 2.0 (1.1–3.8) | 2.7 (1.0–7.6) | 2.1 (0.9–5.0) | 0 | 1.0 (0.5–1.9) | 100 (Z = −6.17, p < 0.001)* | 93.6 (Z = −4.91, p < 0.001)* |
| Wajir | -ns | -ns | -ns | -ns | -ns | -ns | 0 | 0 | -ns | -ns |
| Overall | 13.2 (11.0–15.9) | 15.3 (13.3–17.5) | 1.8 (1.1–2.8) | 2.4 (1.8–3.2) | 1.2 (0.8–1.9) | 1.3 (1.0–1.7) | 0.5 (0.2–1.3) | 1.0 (0.7–1.6) | 96.1 (Z = −6.73, p < 0.001)* | 93.3 (Z = −12.34, p < 0.001)* |
-nsIndicates counties which had not had routine parasitological monitoring, hence, surveys were not conducted in these counties during Year 1, Year 3, and Year 5 assessments.
*
Indicates statistically significant relative reductions since Year 1 (noting that this could be a reflection of sampling technique, and noting also that oftentimes reductions have not been sustained).