Table 3.
Meta-analysis of studies reporting the prevalence of VI animals.
| No. prevalence inputs | Sample size (No. animals) | Weighted mean estimate | Confidence Interval (95%) | I2 (%) | |
|---|---|---|---|---|---|
| Overall | 123 | 1,169,170 | 4.37 | (3.10–5.82) | 99.85 |
| Subgroup a | |||||
| UN Region | |||||
| Europe | 49 | 1,093,215 | 2.38 | (1.28–3.75) | 99.87 |
| North America | 29 | 49,605 | 6.95 | (3.49–11.38) | 99.59 |
| South America | 3 | 9,638 | 1.13 | (0.00–3.96) | 91.47 |
| East Asia | 10 | 3,716 | 11.22 | (3.74–21.77) | 98.53 |
| West Asia | 13 | 3,399 | 5.35 | (1.43–11.24) | 97.19 |
| South Asia | 10 | 4,219 | 1.80 | (0.22–4.44) | 94.65 |
| Australia | 2 | 1,627 | 1.35 | (0.00–4.54) | 78.37 |
| North Africa | 2 | 268 | 17.88 | (5.12–35.83) | 89.47 |
| Sub-Saharan Africa | 5 | 3,483 | 4.87 | (0.00–18.54) | 99.33 |
| Period | |||||
| 1982–1991 | 23 | 18,232 | 2.82 | (1.15–5.06) | 97.85 |
| 1992–2001 | 22 | 21,989 | 7.78 | (3.33–13.75) | 99.44 |
| 2002–2016 | 45 | 1,119,545 | 3.04 | (1.44–5.11) | 99.94 |
| Not specified | 33 | 9,404 | 5.80 | (3.23–9.00) | 96.67 |
| Production system | |||||
| Beef | 20 | 8,440 | 7.80 | (2.83–14.76) | 98.88 |
| Dairy | 46 | 17,023 | 2.26 | (1.10–3.73) | 96.15 |
| Mixed | 23 | 694,310 | 7.37 | (4.48–10.86) | 99.48 |
| Not specified | 34 | 449,397 | 4.03 | (1.82–6.96) | 99.86 |
| Age group | |||||
| ≤6 months | 20 | 1,016,089 | 4.18 | (1.91–7.18) | 99.94 |
| >6 months | 27 | 24,058 | 1.37 | (0.52–2.50) | 96.13 |
| Mixed | 21 | 54,833 | 2.08 | (0.52–4.40) | 99.38 |
| Not specified | 55 | 74,190 | 7.56 | (4.82–10.81) | 99.52 |
| Vaccination | |||||
| Yes | 8 | 3,316 | 7.84 | (1.20–18.89) | 98.46 |
| No | 46 | 691,269 | 2.38 | (0.99–4.22) | 99.13 |
| Not specified | 69 | 474,585 | 5.68 | (3.84–7.81) | 99.73 |
| Clinical signs | |||||
| Yes | 66 | 36,196 | 7.11 | (4.81–9.79) | 98.65 |
| No | 8 | 3,840 | 5.24 | (1.39–11.04) | 93.25 |
| Not specified | 49 | 1,129,134 | 1.56 | (0.68–2.69) | 99.88 |
| Programme | |||||
| Yes | 15 | 1,067,930 | 1.85 | (0.30–4.32) | 99.96 |
| No | 3 | 1,526 | 1.61 | (0.00–6.12) | 92.62 |
| Not specified | 105 | 99,714 | 4.94 | (3.44–6.65) | 99.14 |
| Diagnostic method b | |||||
| Direct detection method | 13 | 3,051 | 9.30 | (3.37–17.54) | 97.36 |
| RT-PCR | 31 | 21,802 | 5.95 | (2.98–9.74) | 98.79 |
| AG ELISA | 29 | 361,629 | 3.00 | (1.31–5.24) | 98.99 |
| Cell culture-based system | 26 | 18,202 | 1.85 | (0.61–3.59) | 97.19 |
| Mixed | 24 | 764,486 | 5.09 | (2.14–9.08) | 99.91 |
aAll p-values except for Australia (p = 0.03) were ≤0.01 and were calculated using the Cochran’s Q-test.
bThe description of the diagnostic methods is provided in Table 1.