Nicolette Zhou

Dr. Nicolette Zhou

Department of Environmental and Occupational Health Science, University of Washington; 4225 Roosevelt Way NE Suite 100, Seattle, WA 98125, USA
orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2023 in The American Journal of Tropical Medicine and Hygiene
Verified
Journal Article
Open access
PDF file
NZNicolette Zhou
Nicolette Zhou
AOAngelo Ong
Angelo Ong
CFChristine Fagnant-Sperati
Christine Fagnant-Sperati
JHJoanna Harrison
Joanna Harrison
AKAlexandra Kossik
Alexandra Kossik
JMJohn Scott Meschke
John Scott Meschke
: Salmonella enterica serovar (Salmonella Typhi) is the causative bacterial agent of typhoid fever. Environmental surveillance of wastewater and wastewater-impacted surface waters has proven effective in monitoring various pathogens and has recently been applied to Salmonella Typhi. This study evaluated eight sample collection and concentration methods with 12 variations currently being developed and used for Salmonella Typhi surveillance globally to better understand the performance of each method based on its ability to detect Salmonella Typhi and its feasibility. Salmonella Typhi strains Ty21a and Ty2 were seeded to influent wastewater at known concentrations to evaluate the following methods: grab sampling using electropositive filters, centrifugation, direct enrichment, or membrane filtration and trap sampling using Moore swabs. Concentrated samples underwent nucleic acid extraction and were detected and/or quantified via quantitative polymerase chain reaction (qPCR). Results suggest that all methods tested can be successful at concentrating Salmonella Typhi for subsequent detection by qPCR, although each method has its own strengths and weaknesses, including the Salmonella Typhi concentration it is best suited for, with a range of positive detections observed as low as 0.1–0.001 colony-forming units (CFU) Ty21a/mL and 0.01 CFU Ty2/mL. These factors should be considered when identifying a method for environmental surveillance and will greatly depend on the use case planned.