Susanna Lenz

A pictographic representation of the text abstract showing wastewater and epidemiologic data flow and data integration. To understand the utility of healthcare facility-level wastewater surveillance (WWS) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it is important to correlate wastewater SARS-CoV-2 RNA detection with the number of clinical infections. WWS for SARS-CoV-2 was performed at three skilled nursing facilities (SNFs) over 25 weeks. Electronegative membrane filtration (enMF) and Nanotrap® Magnetic Virus Particles (NP) virus concentration methods were compared. Extracts were tested by droplet digital polymerase chain reaction. Spearman's correlations (ρ) between wastewater virus RNA concentrations and infection counts were calculated. From split wastewater samples, enMF recovered higher SARS-CoV-2 RNA concentrations than NP. Combining data from all facilities, the median concentrations were 53.0 versus 38.6 gc/100 mL for enMF and NP, respectively (p = 0.001). Using enMF, correlations were moderate to strong at SNF A (ρ ranged 0.67–0.86, all p-values <0.001). Weak to moderate correlations may reflect the sampled manhole not representing the entire facility (SNF B, ρ ranged 0.47–0.72, p-values ranged <0.001–0.12) and longitudinal data gaps from summer heat and equipment maintenance (SNF C, ρ ranged 0.14–0.59, p-values ranged<0.01 to 0.52). WWS can be a valuable tool for tracking dynamics of SARS-CoV-2 infections in healthcare facilities.

Background: Wastewater surveillance at healthcare facilities for carbapenem-resistant (CR) bacteria harboring carbapenemase genes could result in earlier detection of circulating or emerging antimicrobial resistance (AR) threats. However, knowledge gaps exist regarding the CR bacterial community and carbapenemase genes present in facility wastewater and plumbing, which need to be addressed. Methods: Wastewater effluent samples from three skilled nursing facilities (SNFs) (Georgia, USA) were collected weekly over six months. Selective chromogenic media were examined for their performance in screening the samples for targeted CR bacteria. Culture-dependent and culture-independent methods (ie, PCR) were applied to enriched wastewater samples (n = 73) to screen isolates and pooled samples for the most common carbapenemase genes circulating in the United States (blaKPC, blaNDM, blaVIM, blaOXA-48-like, and blaIMP), and method sensitivity was compared. Whole genome sequencing (WGS) was used to identify all AR genes present in isolates. Results: Bacteria (n = 209 isolates) were identified using MALDI-TOF and included >20 different genera. Clinically relevant (Acinetobacter baumannii complex, Enterobacter cloacae complex, Enterococcus faecium, Stenotrophomonas spp.) and environmental/opportunistic (Comamonas spp., Pandoraea spp., Pseudomonas putida group) CR bacteria were identified in each of the three SNFs. In Facility A and C, only blaKPC was detected in 9 (26.5%) of 34 and 14 (11.4%) of 123 recovered isolates, respectively. There were no PCR-positive results in Facility B. WGS confirmed the presence or absence of all genes screened by PCR (100% concordance). Conclusions: These data provide a proof-of-concept and insights into CR bacteria present in healthcare facility wastewater using culture, PCR, and sequencing methods.

Wastewater surveillance at healthcare facilities for carbapenem-resistant (CR) bacteria harboring carbapenemase genes could result in earlier detection of circulating or emerging antimicrobial resistance (AR) threats. However, knowledge gaps exist regarding the CR bacterial community and carbapenemase genes present in facility wastewater and plumbing, which need to be addressed. Wastewater effluent samples from three skilled nursing facilities (SNFs) (Georgia, USA) were collected weekly over six months each. Selective chromogenic media were examined for their performance in screening the samples for targeted CR bacteria. Culture-dependent and culture-independent methods (i.e., PCR) were applied to enriched wastewater samples (n=73) to screen isolates and pooled samples for the most common carbapenemase genes circulating in the United States ( bla _KPC , bla _NDM , bla _VIM , bla _OXA-48-like , and bla _IMP ), and method sensitivity was compared. Whole genome sequencing (WGS) was used to identify all AR genes present in isolates. Bacteria (n=209 isolates) were identified using MALDI-TOF and included >20 different genera. Clinically relevant ( Acinetobacter baumannii complex, Enterobacter cloacae complex, Enterococcus faecium, Stenotrophomonas spp.) and environmental/opportunistic ( Comamonas spp., Pandoraea spp ., Pseudomonas putida group) CR bacteria were identified in each of the three SNFs. In Facility A and C, only bla _KPC was detected in 9 (26.5%) of 34 and 14 (11.4%) of 123 recovered isolates, respectively. There were no PCR-positive results in Facility B. WGS confirmed the presence or absence of all genes screened for by PCR (100% concordance). These data provide a proof of concept and insights into CR bacteria present in healthcare facility wastewater using culture, PCR, and sequencing methods.

The purpose of this study was to determine the feasibility of facility-level wastewater surveillance in the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in skilled nursing facility (SNF) wastewater using three concentration methods, as well as a proof-of-concept for antimicrobial resistance (AR) genes/organisms detection. Wastewater effluent samples were collected from an SNF over an 8-week period. Wastewater was concentrated using electronegative membrane filtration (enMF), polyethylene glycol precipitation, and Nanotrap® magnetic virus particles (NP). Quantification of the genome copy concentration from SARS-CoV-2 and bovine respiratory syncytial virus (BRSV), a SARS-CoV-2 surrogate spiked into all samples, was performed with droplet digital polymerase chain reaction (ddPCR). Wastewater sample aliquots were also enriched in microbiological culture media and screened for organisms with AR phenotypes on selective and differential agars. Multiplex real-time PCR was used to detect a broad array of carbapenem resistance genes. SARS-CoV-2 was detected and quantified from a single enMF-concentrated wastewater sample. The highest concentration of BRSV came from enMF-concentrated samples. Klebsiella, Enterobacter, Citrobacter, and Escherichia coli exhibiting AR phenotypes were successfully detected using culture-dependent approaches. Culture-independent, multiplex PCR indicated that blaKPC was the main carbapenemase gene detected in wastewater samples. Facility-level wastewater surveillance could be a useful strategy for SNFs.