Table 2.
The combined prevalence of Echinococcus infection in sheep in China.
| No. studies | No. examined | No. positive | % (95% CI*) | Heterogeneity | Univariate meta-regression | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| χ 2 | P-value | I2(%) | P-value | Coefficient (95% CI) | ||||||
| Season | 0.018 | 0.209 (0.036 to 0.382) | ||||||||
| Autumn | 12 | 104,273 | 54,310 | 44.70% (30.93–58.88) | 5,543.24 | 0.00 | 99.8 | |||
| Summer | 10 | 8,468 | 1,778 | 31.07% (14.95–49.94) | 2,235.77 | 0.00 | 99.6 | |||
| Winter | 4 | 26,340 | 1,939 | 19.48% (10.59–30.26) | 265.91 | < 0.01 | 98.9 | |||
| Spring | 4 | 886 | 186 | 15.42% (3.65–33.06) | 113.17 | < 0.01 | 97.3 | |||
| Age* | 0.016 | -0.309 (-0.560 to -0.057) | ||||||||
| Old sheep | 10 | 2,887 | 1,203 | 35.89% (21.38–51.82) | 632.93 | < 0.01 | 98.6 | |||
| Adult sheep | 27 | 122,919 | 55,883 | 24.67% (14.00–37.20) | 27,211.82 | 0.00 | 99.9 | |||
| Lamb | 8 | 14,362 | 411 | 5.55% (1.56–11.70) | 931.52 | < 0.01 | 99.2 | |||
| Sampling | <0.0001 | -0.325 (-0.447 to -0.203) | ||||||||
| year | 2000 o rbefore | 17 | 541,354 | 148,835 | 55.91% (42.96–68.46) | 69106.07 | 0.00 | 100 | ||
| 2001 to 2010 | 22 | 58,989 | 16,077 | 33.23% (21.32–46.34) | 20,590.54 | 0.00 | 99.9 | |||
| 2011 or late | 23 | 177,318 | 10,269 | 13.86% (9.94–18.3) | 9,917.86 | 0.00 | 99.8 | |||
| Method | 0.644 | -0.072 (-0.376 to 0.232) | ||||||||
| Serological testing | 5 | 9,855 | 2,413 | 28.44% (9.33–52.9) | 1,781.97 | 0.00 | 99.8 | |||
| Anatomical touch detection | 66 | 814,195 | 188,501 | 29.77% (24.09–35.79) | 158,630.05 | 0.00 | 100 | |||
| Ultrasonic testing | 3 | 1,293 | 418 | 23.40% (7.11–45.38) | 124.98 | < 0.01 | 98.4 | |||
| Region* | 0.022 | -0.438 (-0.813 to -0.063) | ||||||||
| Southwestern | 3 | 531 | 278 | 51.09% (11.51–89.86) | 212.49 | < 0.01 | 99.1 | |||
| Northern | 2 | 811 | 193 | 31.85% (0.00–99.00) | 525.95 | < 0.01 | 99.8 | |||
| Northwestern | 67 | 824,817 | 191,658 | 31.23% (25.53–37.23) | 160,941.08 | 0.00 | 100 | |||
| Northeastern | 2 | 247 | 5 | 1.89% (0.42–4.15) | 0.49 | 0.49 | 0 | |||
| Gender | 0.885 | 0.024 (-0.298 to 0.346) | ||||||||
| Ram | 3 | 1,855 | 1,048 | 51.55% (32.72–70.16) | 24.74 | < 0.01 | 91.9 | |||
| Ewe | 6 | 4,156 | 2,155 | 48.86% (30.51–67.36) | 635.87 | < 0.01 | 99.2 | |||
| Infected organs | ||||||||||
| Liver | 34 | 597,815 | 58,344 | 20.10% (15.19–25.51) | 40,471.45 | 0.00 | 99.9 | 0.004 | -0.246 (-0.415to -0.076) | |
| Both* | 25 | 154,439 | 58,206 | 18.87% (8.92–31.44) | 53,576.89 | 0.00 | 100 | |||
| lung | 29 | 595,469 | 58,206 | 8.23% (4.42–13.05) | 51,471.17 | 0.00 | 99.9 | |||
| other | 7 | 120,420 | 2,505 | 2.50% (0.00–10.62) | 8,995.12 | 0.00 | 99.9 | |||
| Echinococcus species | 0.0817 | -0.427 (-0.907 to 0.054) | ||||||||
| Echinococcus granulosus | 9 | 15,415 | 5,306 | 32.05% (11.49–57.10) | 7,626.00 | 0.00 | 99.9 | |||
| Echinococcus multilocularis | 3 | 2,175 | 65 | 2.99% (0.19–8.74) | 68.09 | < 0.01 | 97.1 | |||
| Sample type | 0.990 | 0.001 (-0.205 to 0.207) | ||||||||
| Serum | 7 | 14,296 | 2,666 | 30.44% 13.85–50.19) | 2,934.59 | 0.00 | 99.8 | |||
| Organs | 71 | 812,110 | 189,468 | 30.52% (24.97–36.37) | 158,932.62 | 0.00 | 100 | |||
| Sampling location | 0.016 | 0.204 ( 0.038 to 0.370) | ||||||||
| Pasture | 18 | 16,547 | 4,253 | 39.82% (21.45–59.78) | 9,520.34 | 0.00 | 99.8 | |||
| Slaughterhouse | 48 | 699,590 | 138,966 | 29.74% (22.60–37.42) | 141,267.97 | 0.00 | 100 | |||
| Quality level | 0.034 | 0.330 (0.026 to 0.633) | ||||||||
| Low | 3 | 2,369 | 1187 | 62.05% (27.76–90.63) | 494.6 | < 0.01 | 99.6 | |||
| Medium | 48 | 762,128 | 175,450 | 31.23% (24.48–38.41) | 140,929.80 | 0.00 | 100 | |||
| High | 23 | 61,909 | 15,497 | 26.63% (16.46–38.23) | 196,36.73 | 0.00 | 99.9 | |||
| Total | 74 | 826,406 | 192,094 | 30.94% (25.51–36.64) | ||||||
CI*: Confidence interval;
NA*: Not applicable;
Age*: Lamb (< 1 year); Adult sheep (1–6 years old); Old sheep (> 6 years old).
Both*: Mixed liver and lung infection.