Comparison of risk factors for SARS-CoV-2 infection among healthcare workers during Omicron and Delta dominance periods in Japan.

BACKGROUND: The risk factors for coronavirus disease (COVID-19) among healthcare workers (HCWs) might have changed since the emergence of the highly immune evasive Omicron variant. AIM: To compare the risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among HCWs during the Delta- and Omicron-predominant periods. METHODS: Using data from repeated serosurveys among the staff of a medical research centre in Tokyo, two cohorts were established: Delta period cohort (N = 858) and Omicron period cohort (N = 652). The potential risk factors were assessed using a questionnaire. Acute/current or past SARS-CoV-2 infection was identified by polymerase chain reaction or anti-nucleocapsid antibody tests, respectively. Poisson regression was used to calculate the risk ratio (RR) of infection risk. FINDINGS: The risk of SARS-CoV-2 infection during the early Omicron-predominant period was 3.4-fold higher than during the Delta-predominant period. Neither working in a COVID-19-related department nor having a higher degree of occupational exposure to SARS-CoV-2 was associated with an increased infection risk during both periods. During the Omicron-predominant period, infection risk was higher among those who spent ≥30 min in closed spaces, crowded spaces, and close-contact settings without wearing mask (≥3 times versus never: RR: 6.62; 95% confidence interval: 3.01-14.58), whereas no such association was found during the Delta period. CONCLUSION: Occupational exposure to COVID-19-related work was not associated with the risk of SARS-CoV-2 infection in the Delta or Omicron period, whereas high-risk behaviours were associated with an increased infection risk during the Omicron period.

5-year Efforts and Operational Results of Virtual Computer Classroom in TUAT

Tokyo University of Agriculture and Technology (TUAT) has provided a university information system based on BYOD (Bring Your Own Device) environment since April 2016. This university information system has provided a brand-new computer system for the classroom, called TUAT Virtual Computer Classroom (TUAT-VCCR), replacing old computer rooms and terminals. The unique feature of this system is to provide a platform-independent computer exercise environment by constructing a TUAT-VCCR that can be accessed via a web browser on an off-campus cloud. This article shares our 5-year efforts and operational reports of TUAT-VCCR and the knowledge gained from the operation. At present, many universities and schools are restricting the use of conventional physical terminal classrooms to prevent contact infections caused by COVID-19 through shared touched items such as keyboards and mice and prevent dense environments in classrooms. At the TUAT, an online course using web conferencing tools has been implemented since April 2020 to prevent the spread of COVID-19 infection. In response to these changes in the place where classes are taken, TUAT-VCCR, which can be used as long as network accessibility is ensured, is one of the ways to facilitate computer exercises in the COVID-19 pandemic. In this article, we also discuss the usage of TUAT-VCCR before and under the COVID-19 pandemic. This article will provide valuable information to other organizations planning similar BYOD initiatives, and we would like to discuss together with the SIGUCCS community how the system should be designed for an unusual situation like the COVID-19 pandemic. © 2022 ACM.

Actual Practice of Short Time Period Implementation of MultipleWeb Conferencing Systems for Online Classes

With the expansion of COVID-19 outbreaks, the lecture environment has changed dramatically. Various activities have been held by distance learning, however, the style of online learning and hybrid learning is also popular. The key to these lectures is the web conferencing tool. The key factor to success in new age lectures is how the web conferencing tool can be adapted to the existing information system. Tokyo University of Agriculture and Technology (TUAT) has developed full online courses from the first semester (spring semester) in April 2020. However, the increase of the infection has remained constant, and TUAT will continue to provide online courses using the web conferencing tool from the second semester (fall semester) in October 2020, and hybrid courses that combine face-to-face teaching. To support this, a campus-wide license was purchased that enables the use of three different web conferencing tools including Zoom Meeting, Cisco Webex, and Google Meet in the suitable applications. For the start of the second semester, the Information Media Center (IMC) has developed a system to integrate with the existing authentication system to enable use of the these three tools. Since we didn't have enough time to implement the system integration, we need to take less than a month (about 3 weeks) from the contract to the start of service. In this presentation, we explain in detail how we designed the system and how it was implemented in order to deploy these systems in a very short time period. We will also mention the implementation issues we faced. By explaining the ideal and reality of the system, we would like to discuss together with the SIGUCCS community how the system should be designed for the unusual situation. © 2022 ACM.