Use of Bluetooth contact tracing technology to model COVID-19 quarantine policies in high-risk closed populations.

Containment measures in high-risk closed settings, like migrant worker (MW) dormitories, are critical for mitigating emerging infectious disease outbreaks and protecting potentially vulnerable populations in outbreaks such as coronavirus disease 2019 (COVID-19). The direct impact of social distancing measures can be assessed through wearable contact tracing devices. Here, we developed an individual-based model using data collected through a Bluetooth wearable device that collected 33.6M and 52.8M contact events in two dormitories in Singapore, one apartment style and the other a barrack style, to assess the impact of measures to reduce the social contact of cases and their contacts. The simulation of highly detailed contact networks accounts for different infrastructural levels, including room, floor, block, and dormitory, and intensity in terms of being regular or transient. Via a branching process model, we then simulated outbreaks that matched the prevalence during the COVID-19 outbreak in the two dormitories and explored alternative scenarios for control. We found that strict isolation of all cases and quarantine of all contacts would lead to very low prevalence but that quarantining only regular contacts would lead to only marginally higher prevalence but substantially fewer total man-hours lost in quarantine. Reducing the density of contacts by 30% through the construction of additional dormitories was modelled to reduce the prevalence by 14 and 9% under smaller and larger outbreaks, respectively. Wearable contact tracing devices may be used not just for contact tracing efforts but also to inform alternative containment measures in high-risk closed settings.

Estimating SARS-CoV-2 infection risk in university dormitories using CO2 pulse injections

Air movement dynamics within three student dormitories were studied with simulated carbon dioxide (CO2) pulse injections to understand SARS-CoV-2 transmission risk. CO2 decay rate, proportion of shared air, and transport time were calculated from dynamic CO2 measurement data within simulated source and adjacent receptor rooms. Applying a Wells-Riley infection risk analysis with these results, the risk of SARS-CoV-2 infection in adjacent rooms ranged from 1% to 58% assuming an average emission rate of 5 quanta per hour and exposure duration of 3.5 days. Door opening status was very influential in resulting risk and vertical transport from source to above rooms was observed in all dormitories. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

Measurement of Phthalates in Settled Dust in University Dormitories and Its Implications for Exposure Assessment

Six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), and di(n-octyl) phthalate (DOP) in settled dust on different indoor surfaces were measured in 30 university dormitories. A Monte Carlo simulation was used to estimate college students' exposure via inhalation, non-dietary ingestion, and dermal absorption based on measured concentrations. The detection frequencies for targeted phthalates were more than 80% except for DEP (roughly 70%). DEHP was the most prevalent compound in the dust samples, followed by DnBP, DOP, and BBzP. Statistical analysis suggested that phthalate levels were higher in bedside dust than that collected from table surfaces, indicating a nonuniform distribution of dust-phase phthalates in the sleep environment. The simulation showed that the median DMP daily intake was 0.81 μg/kg/day, which was the greatest of the targeted phthalates. For the total exposures to all phthalates, the mean contribution of exposures during the daytime and sleeping time was 54% and 46%, respectively.

Psychological State and Subjective Environmental Perception of College Students Residing in Dormitories during Quarantine: A Case Study

Quarantine is one of the effective approaches to control the spread of COVID-19. However, prolonged isolation may harm the health of residents, especially students, who are quarantined in dormitories. This study surveyed students' behaviors, living environment, and psychological state through an online questionnaire. The results showed that during the isolation period, the participants' discomfort mainly came from high temperatures, high humidity, loud sounds, and dark lighting. Moreover, about half of the students experienced severe anxiety or depression, with poor sleep and an unclear mind being the most common problems. Additionally, this study focused on exploring the correlations between environmental perceptions and the psychological state of isolated students, that were identified to be significant. Furthermore, as isolation time was prolonged, the psychological state of isolated students worsened, and the most significant factor changed from thermal sensations to acoustic sensations. Interestingly, the psychological state of males was worse than females, and they were more easily affected by their thermal and acoustic environments. Therefore, keeping the environment comfortable has a positive influence on maintaining the good psychological condition of people in isolation. This study can provide suggestions for the improvement of indoor environments and for the mental health of people in isolation and in other similar situations.

Lockdown in Chinese university dormitories: Significant increase in negative feelings and time perception distortion.

The COVID-19 pandemic has led to a global crisis resulting in lockdowns worldwide. Studies found that these could amplify negative affects predictive of disturbances in time perception. However, all existing studies on this topic concentrated on the general population during a lockdown at home. There was no research on university students living in dormitories. This study fills a gap in the literature by investigating the affective states and awareness of the passage of time of Chinese university students during an exceptional dormitory lockdown. Using a snowball sampling approach, this web-based study recruited 225 volunteers (136 girls, 17-27 years old) during a dormitory lockdown. The online survey consisted of questions on demographic information, affective states (the Chinese version of the depression anxiety stress scales-21 (DASS-21) on depression, anxiety, and stress), and sense of the passage of time (the translated version of the assessment of passage of time over daily, weekly and yearly periods). The researchers shared the questionnaire link via the social media application WeChat. The study applied descriptive statistics and column charts to represent students' affective states and sense of the passage of time under extreme conditions and Pearson's correlation analysis to examine the impact of affective states on their sense of time. The study's results indicate that the dormitory lockdown caused a significant increase in all depression, anxiety, and stress categories of the DASS-21, as well as a distortion of the sense of time passing. However, the direction of the distortion differed from that in previous studies. Moreover, a Pearson correlation analysis showed that none of the three negative affects could be associated with students' sense of time. The findings of this study indicate an increased vulnerability of students due to the lockdown. Their emotions were strongly affected, requiring particular interventions to preserve their mental well-being. In addition, they showed a different distortion direction of time passage. Finally, they differed in the correlations between negative affect and the sense of passage of time compared to the general population in lockdown at home. This shows a need to investigate the impact of psychological states on students' routines and quality of life in emergencies. This study's scope should be expanded by incorporating additional factors pertaining to the passage of time and by integrating cross-cultural comparisons.

CFD Simulations of Ventilation and Interunit Dispersion in Dormitory Complex: A Case Study of Epidemic Outbreak in Shanghai.

Since the beginning of March 2022, a new round of COVID-19 outbreaks in Shanghai has led to a sharp increase in the number of infected people. It is important to identify possible pollutant transmission routes and predict potential infection risks for infectious diseases. Therefore, this study investigated the cross-diffusion of pollutants caused by natural ventilation, including external windows and indoor ventilation windows, under three wind directions in a densely populated building environment with the CFD method. In this study, CFD building models were developed based on an actual dormitory complex and surrounding buildings under realistic wind conditions to reproduce the airflow fields and transmission paths of pollutants. This paper adopted the Wells-Riley model to assess the risk of cross-infection. The biggest risk of infection was when a source room was located on the windward side, and the risk of infection in other rooms on the same side as the source room was large in the windward direction. When pollutants were released from room 8, north wind resulted in the highest concentration of pollutants in room 28, reaching 37.8%. This paper summarizes the transmission risks related to the indoor and outdoor environments of compact buildings.

Integrative Effects between a Bubble and Seal Program and Workers' Compliance to Health Advice on Successful COVID-19 Transmission Control in a Factory in Southern Thailand.

Applying health measures to prevent COVID-19 transmission caused disruption of businesses. A practical plan to balance public health and business sustainability during the pandemic was needed. Herein, we describe a "Bubble and Seal" (B&S) program implemented in a frozen seafood factory in southern Thailand. We enrolled 1539 workers who lived in the factory dormitories. First, the workers who had a high fatality risk were triaged by RT-PCR tests, quarantined and treated if they had COVID-19. Newly diagnosed or suspected COVID-19 workers underwent the same practices. The non-quarantined workers were regulated to work and live in their groups without contact across the groups. Workers' personal hygiene and preventive measures were strongly stressed. Between the 6th and 9th weeks of the program, the post-COVID-19 infection status (PCIS) of all participants was evaluated by mass COVID-19 antibody or RT-PCR tests. Finally, 91.8% of the workers showed positive PCIS, which was above the number required for program exit. Although no workers had received a vaccination, there was only one case of severe COVID-19 pneumonia, and no evidence of COVID-19 spreading to the surrounding communities. Implementation of the B&S program and workers' adherence to health advice was the key to this success.

Exploring theory-based behavioral interventions promoting COVID-19 prevention and healthcare-seeking for migrant worker men in Singapore: a qualitative study.

BACKGROUND: The first wave of COVID-19 during April to July 2020 in Singapore largely affected the migrant workers living in residential dormitories. A government taskforce working with dormitory operators, employers and non-government agencies came together to deliver behavioral interventions and health care services for migrant worker as dorms were imposed movement restrictions. To fill the research gap in understanding movement restriction experiences of migrant workers, this research seeks to describe dormitory contexts and explore behavior change related to both prevention of transmission as well as healthcare seeking for COVID-19 among male migrant workers. METHODS: With social constructivism as the foundation for this study, 23 telephone interviews were conducted with Bangladeshi and Indian migrant workers. A theory-informed, data-driven conceptual framework, characterized by the "Four Ss": Sensitization, Surveillance, Self-preservation, and Segregation was first generated and later used to frame second-stage, more in-depth, thematic analyses. An effective multipronged approach was documented, persuading migrant workers in our case-study to improve hygiene and follow some safe distancing measures, and adhere to help-seeking when symptomatic. RESULTS: Rapid collective adaptation was demonstrated; it was propped up by effective harnessing of infrastructure and technology. While technology and digital platforms were central to shaping Sensitization for prevention-related behaviors, interpersonal communication, especially peer-sharing, was key to normalizing and accepting healthcare delivery and norms about healthcare seeking. Interpersonal factors particularly supported successful implementation of case-detection Surveillance, stimulating Self-preserving and acceptance of rules, and was found helpful to those Segregated in recovery facilities. In contrast, encouraging prevention-related behaviors relied more heavily on multiple online-platforms, phone-based e-learning/knowledge testing, e-monitoring of behavior, as well as interpersonal exchanges. CONCLUSION: Overall, the findings showed that the conception of the Four Ss helped inform intervention strategies. Anchoring these towards optimal use of technology and harnessing of interpersonal communication for prevention and promotion of healthcare seeking in the planning of future Infectious Disease outbreaks in closed institutional settings is recommended.

Analysis of the influence of the stay-at-home order on the electricity consumption in Chinese university dormitory buildings during the COVID-19 pandemic.

During the COVID-19 pandemic, strict stay-at-home orders have been implemented in many Chinese universities in virus-hit regions. While changes in electricity consumption in the residential sector caused by COVID-19 have been thoroughly analysed, there is a lack of insight into the impact of the stay-at-home order on electricity consumption in university dormitory buildings. Based on questionnaire survey results, this study adopted the statistical Kaplan-Meier survival analysis to analyse the energy-use behaviours of university students in dormitories during the COVID-19 pandemic. The electricity load profiles of the dormitory buildings before and during the implementation of the stay-at-home order were generated and compared to quantitatively analyse the influence of COVID-19 pandemic on the energy-use behaviours of university students, and the proposed load forecasting method was validated by comparing the forecasting results with monitoring data on electricity consumption. The results showed that: 1) during the implementation of the stay-at-home order, electricity consumption in the university dormitory buildings increased by 41.05%; 2) due to the increased use of illuminating lamps, laptops, and public direct drinking machines, the daily electricity consumption increased most significantly from 13:00 to 18:00, with an increase rate of 97.15%; and 3) the morning peak shifted backward and the evening peak shifted forward, demonstrating the effect of implementing the stay-at-home order on reshaping load profiles.

Association of Shared Living Spaces and COVID-19 in University Students, Wisconsin, USA, 2020.

We describe characteristics associated with having coronavirus disease (COVID-19) among students residing on a university campus. Of 2,187 students, 528 (24.1%) received a COVID-19 diagnosis during fall semester 2020. Students sharing a bedroom or suite had approximately twice the odds of contracting COVID-19 as those living alone.

Interventions to Disrupt Coronavirus Disease Transmission at a University, Wisconsin, USA, August-October 2020.

University settings have demonstrated potential for coronavirus disease (COVID-19) outbreaks; they combine congregate living, substantial social activity, and a young population predisposed to mild illness. Using genomic and epidemiologic data, we describe a COVID-19 outbreak at the University of Wisconsin-Madison, Madison, Wisconsin, USA. During August-October 2020, a total of 3,485 students, including 856/6,162 students living in dormitories, tested positive. Case counts began rising during move-in week, August 25-31, 2020, then rose rapidly during September 1-11, 2020. The university initiated multiple prevention efforts, including quarantining 2 dormitories; a subsequent decline in cases was observed. Genomic surveillance of cases from Dane County, in which the university is located, did not find evidence of transmission from a large cluster of cases in the 2 quarantined dorms during the outbreak. Coordinated implementation of prevention measures can reduce COVID-19 spread in university settings and may limit spillover to the surrounding community.

Development of Wastewater Pooled Surveillance of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) from Congregate Living Settings.

Wastewater-based monitoring for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the individual building level could be an efficient, passive means of early detection of new cases in congregate living settings, but this approach has not been validated. Preliminary samples were collected from a hospital and a local municipal wastewater treatment plant. Molecular diagnostic methods were compared side by side to assess feasibility, performance, and sensitivity. Refined sample collection and processing protocols were then used to monitor two occupied dormitory complexes (n = 105 and 66) over 8 weeks. Wastewater results were validated using known case counts from external clinical testing of building occupants. Results confirm that ultracentrifugation from a 24-h composite collection had a sensitivity of 96.2% and a specificity of 100%. However, the method could not distinguish new infectious cases from persistent convalescent shedding of SARS-CoV-2 RNA. If the detection of convalescent shedding is considered a false positive, then the sensitivity is 100% and specificity drops to 45%. It was determined that the proposed approach constitutes a highly sensitive wastewater surveillance method for detecting SARS-CoV-2, but it could not distinguish new infectious cases from persistent convalescent shedding. Future work must focus on approaches to distinguish new infections from convalescent shedding to fully realize the potential of building wastewater as a surveillance tool for congregate living. IMPORTANCE Some of the most severe outbreaks of COVID-19 have taken place in places where persons live together, such as nursing homes. Wastewater testing from individual buildings could be used for frequent pooled surveillance of virus from all occupants, including those who are contagious, with or without symptoms. This work provides a sensitive practical method for detecting infected individuals, as validated in two building complexes housing occupants who underwent frequent clinical testing performed by external entities. Although this sensitive method could be deployed now for pooled surveillance as an early warning system to limit outbreaks, the study shows that the approach will require further refinement to differentiate contagious, newly infected individuals from persons who have persistent viral fragments shedding in their stool outside the contagious period.

Promoting COVID-19 prevention strategies in student dormitory setting: A qualitative study.

OBJECTIVE: To explore the risk perceptions and COVID-19 prevention practices of dormitory residents in Indonesia. Participants: Nineteen dormitory residents, 3 staff and 1 dormitory manager were recruited from the Saint Theresa Avila student dormitory. Methods: This qualitative study used individual interviews and framework analysis. Results: Generally, the study confirms that there is a gap between risk perception and COVID-19 prevention practices among dormitory residents. There are barriers in accessing hand washing facilities and in complying with COVID-19 prevention protocols including not wearing masks, not following quarantine procedures and visiting friends' rooms. Conclusion: Dormitory managers and staff should repeatedly remind residents to wear masks and maintain safe distance through sending short messages on dormitory social media groups. In addition to psychological assistance and basic supplies during self-quarantine, providing sanitizer and installing posters detailing the hand-washing steps are essential at each hand-washing facility in the dormitory.

COVID-19 containment on a college campus via wastewater-based epidemiology, targeted clinical testing and an intervention.

Wastewater-based epidemiology has potential as an early-warning tool for determining the presence of COVID-19 in a community. The University of Arizona (UArizona) utilized WBE paired with clinical testing as a surveillance tool to monitor the UArizona community for SARS-CoV-2 in near real-time, as students re-entered campus in the fall. Positive detection of virus RNA in wastewater lead to selected clinical testing, identification, and isolation of three infected individuals (one symptomatic and two asymptomatic) that averted potential disease transmission. This case study demonstrated the value of WBE as a tool to efficiently utilize resources for COVID-19 prevention and response. Thus, WBE coupled with targeted clinical testing was further conducted on 13 dorms during the course of the Fall semester (Table 3). In total, 91 wastewater samples resulted in positive detection of SARS-CoV-2 RNA that successfully provided an early-warning for at least a single new reported case of infection (positive clinical test) among the residents living in the dorm. Overall, WBE proved to be an accurate diagnostic for new cases of COVID-19 with an 82.0% positive predictive value and an 88.9% negative predictive value. Increases in positive wastewater samples and clinical tests were noted following holiday-related activities. However, shelter-in-place policies proved to be effective in reducing the number of daily reported positive wastewater and clinical tests. This case study provides evidence for WBE paired with clinical testing and public health interventions to effectively contain potential outbreaks of COVID-19 in defined communities.