Evaluation of a Wastewater-Based Epidemiological Approach to Estimate the Prevalence of SARS-CoV-2 Infections and the Detection of Viral Variants in Disparate Oregon Communities at City and Neighborhood Scales

Background: Positive correlations have been reported between wastewater SARS-CoV-2 concentrations and a community’s burden of infection, disease or both. However, previous studies mostly compared wastewater to clinical case counts or nonrepresentative convenience samples, limiting their quantitative potential.Objectives: This study examined whether wastewater SARS-CoV-2 concentrations could provide better estimations for SARS-CoV-2 community prevalence than reported cases of COVID-19. In addition, this study tested whether wastewater-based epidemiology methods could identify neighborhood-level COVID-19 hotspots and SARS-CoV-2 variants.Methods: Community SARS-CoV-2 prevalence was estimated from eight randomized door-to-door nasal swab sampling events in six Oregon communities of disparate size, location, and demography over a 10-month period. Simultaneously, wastewater SARS-CoV-2 concentrations were quantified at each community’s wastewater treatment plant and from 22 Newport, Oregon, neighborhoods. SARS-CoV-2 RNA was sequenced from all positive wastewater and nasal swab samples. Clinically reported case counts were obtained from the Oregon Health Authority.Results: Estimated community SARS-CoV-2 prevalence ranged from 8 to 1,687/10,000 persons. Community wastewater SARS-CoV-2 concentrations ranged from 2.9 to 5.1log10 gene copies per liter. Wastewater SARS-CoV-2 concentrations were more highly correlated (Pearson’s r=0.96; R2=0.91) with community prevalence than were clinically reported cases of COVID-19 (Pearson’s r=0.85; R2=0.73). Monte Carlo simulations indicated that wastewater SARS-CoV-2 concentrations were significantly better than clinically reported cases at estimating prevalence (p<0.05). In addition, wastewater analyses determined neighborhood-level COVID-19 hot spots and identified SARS-CoV-2 variants (B.1 and B.1.399) at the neighborhood and city scales.Discussion: The greater reliability of wastewater SARS-CoV-2 concentrations over clinically reported case counts was likely due to systematic biases that affect reported case counts, including variations in access to testing and underreporting of asymptomatic cases. With these advantages, combined with scalability and low costs, wastewater-based epidemiology can be a key component in public health surveillance of COVID-19 and other communicable infections. https://doi.org/10.1289/{"type":"entrez-protein","attrs":{"text":"EHP10289","term_id":"372009674","term_text":"EHP10289"}}EHP10289     

A Web-Based Survey of Oculoplastic Surgeons Regarding the Management of Lower Lid Retraction

Purpose: To survey the opinion of oculoplastic surgeons on the assessment and management of lower eyelid retraction (LLR).

Methods: A web-based survey queried oculoplastic surgeon members of Ojoplast, Spanish and Brazilian Oculoplastic Societies on the management of LLR. The frequency and percentage proportions of the responses were analyzed.

Results: One hundred ninety-six oculoplastic surgeons participated in the survey. The main cause of LLR is post-blepharoplasty (62;31.6%). The most used sign to detect LLR is scleral show. The most common approaches to managing LLR are lateral canthal surgery (164/593;27.6%), autogenous spacers (148/593; 24.9%) and retractor release (131/593;22.1%). The preferred autogenous graft material includes ear cartilage (102/260;39.2%). The majority of surgeons (161/314; 51.3%) recommend massage or steroids injection (80/314;25.5%) for early post-blepharoplasty LLR, while, 54.1% (106/196) of participants suggested waiting for at least six months prior to surgical intervention. Frost suture is used after most LLR surgeries (154/196;91.1%). Incomplete correction is the main complication (111/310;35.8%) of LLR surgery. For mild LLR, 48% of the responders prefer clinical treatment; conversely, severe cases routinely require combined surgical techniques.

Conclusions: Oculoplastic surgeons frequently diagnose LLR based on scleral show. LLR management depends on the cause and severity of lid retraction. Mild cases, in general, receive clinical treatment and severe cases need a combination of surgical techniques and grafts.     

Eye eccentricity modifies the perception of whole-body rotation

In order to explore the effect of gaze orientation on whole-body rotation perception, ten healthy participants were rotated in the dark while fixating on a visual target located either straight ahead or 15° to the right. A vestibular-memory contingent saccade paradigm was used to estimate the rotation perception. The results attest to the participants’ ability to accurately perceive their rotation, based solely on the intrinsic inputs (somesthetic and mainly vestibular), since the correlation between the imposed body rotation and the saccade amplitude was significant and positive. However, the rotation perception was less accurate and of lesser magnitude when the gaze was deviated in the opposite direction to the rotation than when it was either straight ahead or deviated in the direction of the rotation. This can be interpreted as the perceptual equivalent of Alexander’s law.     

Special Feature: Complex Systems: From Chemistry to Systems Biology Special Feature: Complexity in bacterial cell–cell communication: Quorum signal integration and subpopulation signaling in the Bacillus subtilis phosphorelay

A common form of quorum sensing in Gram-positive bacteria is mediated by peptides that act as phosphatase regulators (Phr) of receptor aspartyl phosphatases (Raps). In Bacillus subtilis, several Phr signals are integrated in sporulation phosphorelay signal transduction. We theoretically demonstrate that the phosphorelay can act as a computational machine performing a sensitive division operation of kinase-encoded signals by quorum-modulated Rap signals, indicative of cells computing a “food per cell” estimate to decide whether to enter sporulation. We predict expression from the rapA-phrA operon to bifurcate as relative environmental signals change in a developing population. We experimentally observe that the rapA-phrA operon is heterogeneously induced in sporulating microcolonies. Uninduced cells sporulate rather synchronously early on, whereas the RapA/PhrA subpopulation sporulates less synchronously throughout later stationary phase. Moreover, we show that cells sustain PhrA expression during periods of active growth. Together with the model, these findings suggest that the phosphorelay may normalize environmental signals by the size of the (sub)population actively competing for nutrients (as signaled by PhrA). Generalizing this concept, the various Phrs could facilitate subpopulation communication in dense isogenic communities to control the physiological strategies followed by differentiated subpopulations by interpreting (environmental) signals based on the spatiotemporal community structure.