Comparing solid-based concentration methods for rapid and efficient recovery of SARS-CoV-2 for wastewater surveillance.

As wastewater-based surveillance of SARS-CoV-2 attracts interest globally, there is a need to evaluate and identify rapid and efficient methods for concentrating enveloped viruses in wastewater. When comparing five precipitation/flocculation-based concentration methods (including aluminum hydroxide adsorption-precipitation, AHAP; zinc acetate precipitation, ZAP; skimmed milk flocculation, SMF; FeCl precipitation, FCP; and direct centrifugation, DC), AHAP was found to be the most efficient method in terms of seeded BCoV recovery (50.2 %).

Diversity of bla in carbapenem-resistant opportunistic pathogenic Pseudomonas otitidis in municipal wastewater.

Metallo-β-lactamases (MBLs) encoding carbapenem resistance in wastewater are a well-known serious threat to human health. Twelve Pseudomonas otitidis isolates obtained from a municipal wastewater treatment plant (WWTP) in Hawaii were found to possess a subclass B3 MBL - POM (P. otitidis MBL), with a minimum inhibition concentration (MIC) range of 8-16 mg/L.

Fine-Scale Temporal Dynamics of SARS-CoV-2 RNA Abundance in Wastewater during A COVID-19 Lockdown.

Wastewater is a pooled sampling instrument that may provide rapid and even early disease signals in the surveillance of COVID-19 disease at the community level, yet the fine-scale temporal dynamics of SARS-CoV-2 RNA in wastewater remains poorly understood. This study tracked the daily dynamics of SARS-CoV-2 RNA in the wastewater from two wastewater treatment plants (WWTPs) in Honolulu during a rapidly expanding COVID-19 outbreak and a responding four-week lockdown that resulted in a rapid decrease of daily clinical COVID-19 new cases. The wastewater SARS-CoV-2 RNA concentration from both WWTPs, as measured by three quantification assays (N1, N2, and E), exhibited both significant inter-day fluctuations (10-10 gene copies or GC/L in wastewater liquid fractions, or 10-10 GC/g in solid fractions) and an overall downward trend over the lockdown period.

Inactivation efficiency of plasmid-encoded antibiotic resistance genes during water treatment with chlorine, UV, and UV/HO.

This study assessed the inactivation efficiency of plasmid-encoded antibiotic resistance genes (ARGs) both in extracellular form (e-ARG) and present within Escherichia coli (intracellular form, i-ARG) during water treatment with chlorine, UV (254 nm), and UV/HO. A quantitative real-time PCR (qPCR) method was used to quantify the ARG damage to amp (850 bp) and kan (806 bp) amplicons, both of which are located in the pUC4K plasmid. The plate count and flow cytometry methods were also used to determine the bacterial inactivation parameters, such as culturability and membrane damage, respectively.