Table 2.
Salmonella prevalence in raw, shelled tree nut samples according to retail source and serotypes of isolates recovered from positive samples, based on 375‐g sample size
| Retailer type | No. (%) of samples | No. of points of sale | No. of samples positive for Salmonella | Salmonella prevalence (%)[95% CI] | Salmonella serotype a (No. of isolates) |
|---|---|---|---|---|---|
| Major or big chain supermarkets | 1,381 (40.93) | 168 | 4 | 0.29 [0.08, 0.74] | Muenchen (1), Liverpool (1), Senftenberg (2) |
| Small chain supermarkets | 328 (9.72) | 57 | 1 | 0.30 [0.01, 1.69] | diarizonae O61(1) |
| Discount, variety, or drug stores | 1329 (39.39) | 148 | 6 | 0.45 [0.17, 0.98] | Mbandaka (1), Urbana (1), diarizonae N.N. (1), Give (3) |
| Online | 336 (9.96) | 120 | 4 | 1.19 [0.33, 3.02] | Senftenberg (1), Worthington (1), Montevideo (2), Mbandaka (1), Duisburg (1) |
| Total | 3,374 | 493 | 15 | 0.44 [0.25, 0.73] |
Abbreviation: CI, Clopper–Pearson's 95% confidence interval.
aTwo pistachios samples obtained from online retailers had two different serotypes each.