Lab Matters Summer 2022 | Page 14


Wastewater Surveillance for More Than SARS-CoV-2

by Alessandro Rossi , PhD , infectious disease laboratory chief scientist , Utah Public Health Laboratory ; Stephanie Dela Cruz , group manager , Virginia Division of Consolidated Laboratory Services ; Jessica Maitland , PhD , lead scientist , Virginia Division of Consolidated Laboratories ; Sarah Wright , MS , manager , Environmental Laboratories ; and Erin Morin , MHS , associate specialist , Environmental Health
Over the course of the pandemic , wastewater surveillance has been known for providing bellwether community data on COVID-19 case trends and variant presence through the National Wastewater Surveillance System to inform local , state and national response . As public health laboratories acquire additional resources , they are now considering how this wastewater surveillance infrastructure can also be used to track other pathogens and targets of public health concern .
Utah Public Health Laboratory
The Utah Public Health Laboratory ( UPHL ) is currently the Mountain Regional Laboratory for the US Centers for Disease Control and Prevention ’ s ( CDC ’ s ) national Antibiotic Resistance Laboratory Network ( AR Lab Network ). Given the availability of SARS-CoV-2 surveillance samples collected from Utah wastewater treatment plants ( WTPs ), UPHL started to explore the feasibility of monitoring AR threats in wastewater in fall 2021 .
UPHL has worked to develop methods to isolate Carbapenem-resistant Enterobacterales ( CREs ), a difficult-to-treat bacteria group resistant to last-resort carbapenem antibiotics , and the yeast Candida auris , a multi-drug-resistant nosocomial pathogen not yet detected in Utah . UPHL has been successful in isolating about 300 CREs from 24 of the 32 WTPs sampled . Whole genome sequencing analysis showed that these isolates express carbapenemase ( enzymes inactivating carbapenems ) genes that have also been identified in CRE-colonized individuals resident in Utah . Interestingly , in some instances wastewater isolates were highly genetically related to clinical CRE isolates previously tested at UPHL and shared a similar geographical origin . These preliminary data indicate that wastewater monitoring may provide awareness of a community AR threat and
A ) Wastewater samples plated on a chromogenic medium ( CHROMagar™ mSuperCARBA™ ) plates containing the carbapenem antibiotic meropenem . Pink , blue and purple colonies are selected for further characterization as presumptive CREs . B ) APHL AR Fellow Jorge Chavez , who is leading wastewater AR testing efforts , in action in the lab . Photo : UPHL
inform infection prevention interventions . While UPHL has been able to isolate Candida species from wastewater , establishing a protocol to specifically detect C . auris has been challenging . Work is currently in progress to implement strategies that may suppress the growth of environmental yeasts found in wastewater that are able to break through the selection conditions originally designed for clinical samples .
Virginia Division of Consolidated Laboratory Services
In summer 2021 , the Virginia Division of Consolidated Laboratory Services Salmonella and Norovirus . Wastewater surveillance of these two pathogens has the potential to complement existing DCLS clinical surveillance for seasonal pattern detection and strain characterization trends . The wastewater testing infrastructure already developed for SARS-CoV-2 positions Virginia to be prepared for the next pandemic to be able to quickly address the wastewater surveillance needs for new emerging pathogens . n
12 LAB MATTERS Summer 2022
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