Publications by authors named "Chrystal Landgraff"

Article Synopsis
  • - Wastewater surveillance has proven effective in tracking the spread of SARS-CoV-2, including its variants, particularly at transportation hubs like Toronto Pearson International Airport.
  • - Canadian municipalities, including WWTPs in Ontario, use techniques like qPCR and whole genome sequencing to monitor the virus in wastewater.
  • - Findings from wastewater samples at the airport often identified new viral lineages 1-4 weeks before clinical cases were reported, highlighting the potential for early detection in pandemic response.
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Wastewater-based surveillance is a valuable approach for monitoring COVID-19 at community level. Monitoring SARS-CoV-2 variants of concern (VOC) in wastewater has become increasingly relevant when clinical testing capacity and case-based surveillance are limited. In this study, we ascertained the turnover of six VOC in Alberta wastewater from May 2020 to May 2022.

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Monitoring the communal incidence of COVID-19 is important for both government and residents of an area to make informed decisions. However, continuous reliance on one means of monitoring might not be accurate because of biases introduced by government policies or behaviours of residents. Wastewater surveillance was employed to monitor concentrations of SARS-CoV-2 RNA in raw influent wastewater from wastewater treatment plants serving three Canadian Prairie cities with different population sizes.

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There are no standardized protocols for quantifying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in wastewater to date, especially for population normalization. Here, a pipeline was developed, applied, and assessed to quantify SARS-CoV-2 and key variants of concern (VOCs) RNA in wastewater at Saskatoon, Canada. Normalization approaches using recovery ratio and extraction efficiency, wastewater parameters, or population indicators were assessed by comparing to daily numbers of new cases.

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Salmonella 4,[5],12:i:- are monophasic S. Typhimurium variants incapable of producing the second-phase flagellar antigen. They have emerged since the mid-1990s to become one of the most prevalent Salmonella serotypes causing human disease world-wide.

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with antigenic formula 4,[5],12:i:- is a monophasic variant of serovar Typhimurium that has emerged globally as a human pathogen over the last 3 decades. We describe the closed genomes and plasmids from six 4,[5],12:i:- isolates recovered from stool samples obtained during investigation of human food poisoning cases reported to PulseNet Canada that are suitable for use as reference strains.

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