Community Surveillance of Omicron in Ontario: Wastewater-based Epidemiology Comes of Age

Wastewater-based surveillance of SARS-CoV-2 RNA has been implemented at building, neighbourhood, and city levels throughout the world. Implementation strategies and analysis methods differ, but they all aim to provide rapid and reliable information about community COVID-19 health states. A viable and sustainable SARS-CoV-2 surveillance network must not only provide reliable and timely information about COVID-19 trends, but also provide for scalability as well as accurate detection of known or unknown emerging variants. Emergence of the SARS-CoV-2 variant of concern Omicron in late Fall 2021 presented an excellent opportunity to benchmark individual and aggregated data outputs of the Ontario Wastewater Surveillance Initiative in Canada; this public health-integrated surveillance network monitors wastewaters from over 10 million people across major population centres of the province. We demonstrate that this coordinated approach provides excellent situational awareness, comparing favourably with traditional clinical surveillance measures. Thus, aggregated datasets compiled from multiple wastewater-based surveillance nodes can provide sufficient sensitivity (i.e., early indication of increasing and decreasing incidence of SARS-CoV-2) and specificity (i.e., allele frequency estimation of emerging variants) with which to make informed public health decisions at regional- and state-levels.Ontario Ministry of the Environment, Conservation and Parks|| Genome Canada and Ontario Genomics (OGI-209)||NSERC (ALLRP 555041-20 to C.O.)||Ontario Clean Water Agenc

Harmful algal blooms of the cyanobacterium Microcystis cause deleterious effects in aquatic organisms: Implications for freshwater biodiversity conservation

Anthropogenically driven harmful algal blooms (HABs) continue to increase in frequency and intensity in the Great Lakes. Risks to human health from HABs drives much of the concern that motivates efforts to manage their causes. However, emerging evidence indicates that HAB-associated toxins, such as microcystins, produced by the cyanobacterium Microcystis, can be toxic to aquatic organisms, especially at sublethal concentrations. Whether this poses a threat to aquatic food webs and freshwater biodiversity is unclear, but understanding the risks associated with sublethal exposures requires toxicological assessment at concentrations commensurate with those typically detected in the field. Herein, we present the results of some of our recent studies assessing the toxicity of microcystins produced by a toxigenic strain of Microcystis aeruginosa on key functional traits (survival, growth, reproduction) of zooplankton (Daphnia magna) and fish (Rainbow Trout, and Lake Trout). We further investigated molecular-level impacts using nontargeted proteomics to link sublethal toxicity with adverse outcomes occurring within these organisms. Our results demonstrate that microcystins at naturally occurring concentrations induced sublethal toxicity in all three organisms, including growth and reproductive impairment, oxidative stress, and carcinogenesis. Taken together, our results demonstrate that Microcystis blooms have the potential to cause deleterious health effects in wildlife

Proteomic Profiles of White Sucker (<i>Catostomus commersonii</i>) Sampled from within the Thunder Bay Area of Concern Reveal Up-Regulation of Proteins Associated with Tumor Formation and Exposure to Environmental Estrogens

White sucker (<i>Catostomus commersonii</i>) sampled from the Thunder Bay Area of Concern were assessed for health using a shotgun approach to compile proteomic profiles. Plasma proteins were sampled from male and female fish from a reference location, an area in recovery within Thunder Bay Harbour, and a site at the mouth of the Kaministiquia River where water and sediment quality has been degraded by industrial activities. The proteins were characterized using reverse-phase liquid chromatography tandem to a quadrupole-time-of-flight (LC-Q-TOF) mass spectrometer and were identified by searching in peptide databases. In total, 1086 unique proteins were identified. The identified proteins were then examined by means of a bioinformatics pathway analysis to gain insight into the biological functions and disease pathways that were represented and to assess whether there were any significant changes in protein expression due to sampling location. Female white sucker exhibited significant (<i>p</i> = 0.00183) site-specific changes in the number of plasma proteins that were related to tumor formation, reproductive system disease, and neurological disease. Male fish plasma had a significantly different (<i>p</i> < 0.0001) number of proteins related to neurological disease and tumor formation. Plasma concentrations of vitellogenin were significantly elevated in females from the Kaministiquia River compared to the Thunder Bay Harbour and reference sites. The protein expression profiles indicate that white sucker health has benefited from the remediation of the Thunder Bay Harbour site, whereas white sucker from the Kaministiquia River site are impacted by ongoing contaminant discharges

Estrogen-like Effects in Male Goldfish Co-exposed to Fluoxetine and 17 Alpha-Ethinylestradiol

The antidepressant fluoxetine (FLX) and the synthetic estrogen, 17 alpha-ethinylestradiol (EE2), are present in municipal sewage discharges. To better understand possible interactions between them, male goldfish were exposed to an ethanol control or to nominal concentrations of FLX (0.54 μg/L) and EE2 (5 ng/L) alone and in combination for 14 days. Real-time reverse-transcription polymerase chain reaction was used to assess effects on hepatic gene expression and liquid chromatography tandem mass spectrometry to analyze the plasma proteome. The results showed an increase in estrogen receptor alpha (<i>esr1</i>) and vitellogenin (<i>vtg</i>) gene expression by 1.9–2.4-fold in the FLX and EE2 groups, but this did not reach statistical significance. In contrast, co-exposure up regulated <i>esr1</i> and <i>vtg</i> gene expression by 5.5- and 5.3-fold, respectively. Fluoxetine and EE2 alone did not affect estrogen receptor beta (<i>esr2</i>), but the co-exposure down regulated <i>esr2</i> expression by 50%. There was a significant increase in the number of plasma proteins that were related to endocrine system disorders in the FLX and FLX plus EE2 groups. The level of VTG protein was increased in the plasma from goldfish exposed to EE2, FLX, and FLX plus EE2. Our study demonstrates that low concentrations of FLX and EE2 in a simple mixture produce strong estrogen-like effects in the male goldfish