Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.
Volume 32, Supplement –Summer 2026
SUPPLEMENT ISSUE
Supplement
Evaluation of Detection Methods for Wastewater Surveillance of Antimicrobial-Resistant Bacteria from Healthcare Facilities
Table 5
Effects of sample handling and storage conditions on gene abundance determined by qPCR in study of detection methods for wastewater surveillance of antimicrobial-resistant bacteria from healthcare facilities*
| Factor | 16S rRNA gene | blaKPC | blaVIM | blaOXA-48-like | blaKPC/ 16S rRNA† | blaVIM/ 16S rRNA† |
|---|---|---|---|---|---|---|
| Overall model F (p value) |
1.98 (0.02) |
2.23 (0.008) |
6.33 (<0.001) |
NS |
3.99 (<0.01) |
9.67 (<0.001) |
| Source of variation | ||||||
| Hold time‡ | 38 (0.002) | 25 (0.01) | 30 (<0.001) | NA§ | NS | 31 (<0.001) |
| Hold temp¶ | NS | NS | 16 (0.01) | NA | NS | 10 (0.008) |
| Hold method | 41 (<0.001) | 42 (<0.001) | 30.1 (<0.001) | NA | 27 (<0.001) | 24 (<0.001) |
| Time × temp | NS | NS | 12.5 (0.008) | NA | NS | 11 (0.002) |
| Temp × method | NS | NS | NS | NA | NS | 15 (0.007) |
| Time × method | NS | NS | 9 (0.04) | NA | 22 (<0.001) | 9 (0.006) |
| Time × temp × method | NS | 15 (0.05) | Not est.** | NA | 27 (<0.001) | Not est.** |
*Source of variation is percent of total variation (p value) of type 1 error for the general linearized model. NA, not applicable; NS, not significant; qPCR, quantitative PCR †Calculation based on log10 ARG/mL divided by log10 16S rRNA gene/mL. ‡Hold times were 1, 7, or 29 days. §The overall model was not significant for this gene, ¶Temperature was 4°C, −20°C, or −70°C. #Hold methods: extracted immediately versus raw samples held at temperature, glycerol preserved unprocessed samples, polyethylene glycol concentrated and resuspended samples, or nucleic acids extracted and stored. **These values were not estimable because of limited degrees of freedom.