Table 3.
Proportion of Salmonella serovars isolated from humans, the environment and animals, screening methods, study year, and sampling sites.
| Risk factors | Number of studies | Pooled estimates | Measure of heterogeneity | Publication bias | ||||
|---|---|---|---|---|---|---|---|---|
| Sample size | Number of positive | I2 (95%CI) | Cochran's Q | Heterogeneity I2 (%) | Q-P | Begg and Mazumdar rank Pvalue | ||
| Overall study | ||||||||
| Human | 4 | 604 | 399 | 79.6 (47.3–94.4) | 31.767 | 90.556 | 0.070 | 0.08712 |
| Environment | 6 | 1652 | 636 | 56.5 (24.9–83.6) | 565.624 | 99.116 | 0.707 | 0.28651 |
| Animal | 14 | 4111 | 1733 | 61.6 (39.3–79.8) | 624.205 | 97.917 | 0.307 | 0.39215 |
| Animal/human | 1 | 200 | 146 | — | — | — | — | — |
| Environment/animal | 4 | 181435 | 9489 | 43.2 (11.2–82.1) | 1003.044 | 99.701 | 0.766 | 0.50000 |
| Environment/human | 1 | 69 | 57 | — | — | — | — | — |
|
| ||||||||
| Study year | ||||||||
| 1980–1990 | 1 | 69 | 57 | — | — | — | — | — |
| 1990–2000 | 1 | 50 | 17 | — | — | — | — | — |
| 2000–2010 | 3 | 501 | 681 | 95.8 (3.1–10) | 61.139 | 96.729 | 0.351 | 0.30075 |
| 2010-2021 | 26 | 187549 | 11461 | 59.7 (40.3–76.4) | 6364.154 | 99.607 | 0.328 | 0.00335 |
|
| ||||||||
| Diagnostic technique | ||||||||
| PCR | 15 | 4219 | 2245 | 65.7 (51.1–77.8) | 729.466 | 98.081 | 0.036 | 0.09075 |
| Culture | 8 | 181285 | 9841 | 41.5 (16.7–71.5) | 493.370 | 98.581 | 0.596 | 0.50000 |
| Serotyping | 6 | 2367 | 1182 | 72.1 (34.9–92.5) | 292.016 | 97.945 | 0.237 | 0.22634 |
| MALDI-TOF-MS | 1 | 491 | 39 | — | — | — | — | — |
|
| ||||||||
| Nontyphoidal Salmonella | ||||||||
| S. Typhimurium | 13 | 817 | 885 | 65.6 (34.6–87.3) | 75.133 | 96.007 | 0.322 | 0.50000 |
| S. Enteritidis | 7 | 124 | 166 | (12.7–65.4) | 75.133 | 96.007 | 0.322 | 0.50000 |
|
| ||||||||
| Provinces | ||||||||
| KwaZulu-Natal | 6 | 2492 | 683 | 42.7 (14.7–76.3) | 564.052 | 99.114 | 0.695 | 0.42549 |
| Gauteng | 8 | 1623 | 1452 | 65.6 (39.0–85.1) | 273.845 | 97.444 | 0.247 | 0.50000 |
| Eastern Cape | 6 | 2749 | 800 | 35.6 (15.8–62.1) | 454.089 | 98.899 | 0.285 | 0.04544 |
| North-West | 5 | 691 | 714 | 76.6 (52.1–90.8) | 79.750 | 94.984 | 0.035 | 0.50000 |
| Northern Cape | 1 | 1069 | 30 | — | — | — | — | — |
| Mpumalanga | 1 | 264 | 36 | — | — | — | — | — |
| Limpopo | 2 | 1333 | 122 | — | — | — | — | — |
| Western Cape | 3 | 470 | 158 | 98.7 (68.3–100) | 17.791 | 88.759 | 0.017 | 0.30075 |
PCR = polymerase chain reaction; MALDI-TOF-MS = matrix assisted laser desorption ionization-time of flight mass spectrometry.