Search

We report 5 clustered acute gastroenteritis outbreaks in long-term care facilities in Utah, USA, that were linked to healthcare employees working at multiple facilities. Four outbreaks were caused by norovirus genotype GIX. We recommend continued norovirus surveillance and genotyping to determine contributions of this genotype to norovirus outbreaks.

Wastewater-based epidemiology has emerged as a powerful public health tool to trace new outbreaks, detect trends in infection and provide an early warning of COVID-19 community spread. Here, we investigated the spread of SARS-CoV-2 infections across Utah by characterizing lineages and mutations detected in wastewater samples. We sequenced over 1,200 samples from 32 sewersheds collected between November 2021 and March 2022. Wastewater sequencing confirmed the presence of Omicron (B.1.1.529) in Utah in samples collected on November 19, 2021, up to ten days before its corresponding detection via clinical sequencing. Analysis of diversity of SARS-CoV-2 lineages revealed Delta as the most frequently detected lineage during November, 2021 (67.71%), but it started declining in December, 2021 with the onset of Omicron (B.1.1529) and its sub-lineage BA.1 (6.79%). Proportion of Omicron increased to ∼58% by January 4th 2022 and completely displaced Delta by February 7th, 2022. Wastewater genomic surveillance revealed the presence of Omicron sub-lineage BA.3, a lineage that is yet to be identified from Utah’s clinical surveillance. Interestingly, several Omicron-defining mutations began to appear in early November, 2021 and increased in prevalence across sewersheds from December to January. Our study suggests that tracking epidemiologically relevant mutations is critical in detecting emerging lineages in the early stages of an outbreak. Wastewater genomic epidemiology provides an unbiased representation of community-wide infection dynamics and is an excellent complementary tool to SARS-CoV-2 clinical surveillance, with the potential of guiding public health action and policy decisions.

From July–November 2020, mink (Neogale vison) on 12 Utah farms experienced an increase in mortality rates due to confirmed SARS-CoV-2 infection. We conducted epidemiologic investigations on six farms to identify the source of virus introduction, track cross-species transmission, and assess viral evolution. Interviews were conducted and specimens were collected from persons living or working on participating farms and from multiple animal species. Swabs and sera were tested by SARS-CoV-2 real-time reverse transcription polymerase chain reaction (rRT-PCR) and serological assays, respectively. Whole genome sequencing was attempted for specimens with cycle threshold values