Volume 32, Number 9—September 2026
Research
Clustering and Source Association of Clinical and Nonclinical Listeria monocytogenes Isolates, New York, USA, 2000–20211
Table 1
Listeria monocytogenes clonal complexes significantly associated with either clinical or nonclinical isolates in study of clustering and source association of clinical and nonclinical Listeria monocytogenes isolates, New York, USA, 2000–2021*
| CC | No. clinical isolates | No. nonclinical isolates | OR (95% CI)† | FDR-adjusted p value‡ |
|---|---|---|---|---|
| CCs overrepresented among clinical isolates | ||||
| CC1 | 138 | 50 | 3.30 (2.34–4.72) | <0.001 |
| CC4 | 53 | 11 | 5.45 (2.79–11.63) | <0.001 |
| CC217 | 43 | 11 | 4.37 (2.20–9.46) | <0.001 |
| CC388 | 39 | 11 | 3.95 (1.97–8.60) | <0.001 |
| CC389 | 35 | 7 | 5.57 (2.42–14.93) | <0.001 |
| CC554 |
37 |
9 |
4.58 (2.16–10.85) |
<0.001 |
| CCs overrepresented among nonclinical isolates | ||||
| CC5 | 63 | 205 | 0.29 (0.21–0.39) | <0.001 |
| CC9 | 5 | 56 | 0.09 (0.03–0.23) | <0.001 |
| CC121 | 6 | 27 | 0.24 (0.08–0.59) | <0.001 |
| CC199 | 3 | 43 | 0.07 (0.01–0.23) | <0.001 |
| CC288 | 5 | 26 | 0.20 (0.06–0.54) | <0.001 |
| CC321 | 17 | 80 | 0.22 (0.12–0.37) | <0.001 |
*Only CCs with an FDR-adjusted p value <0.05 are shown. CC, clonal complex; FDR, false discovery rate; OR, odds ratio. †ORs >1 indicate overrepresentation in clinical isolates, whereas ORs <1 indicate overrepresentation in nonclinical isolates. ‡Statistical significance was assessed using 2-sided Fisher exact test followed by FDR correction for multiple comparisons.
1Preliminary results from this study were presented at the 2025 International Association for Food Protection Conference; July 27–30, 2025; Cleveland, Ohio, USA.