Lessons from the COVID-19 pandemic: strategies and challenges for an aging society in Japan

Purpose: This article analyzes the challenges of infectious disease control under a super-aged society through Japan's experience with COVID-19. Design/methodology/approach: This article provides an overview of Japan's COVID-19 measures and their characteristics, discusses their successes and failures, and identifies future challenges. Findings: Japan's basic strategy for COVID-19 consists of three parts: the border defense (Stage 1), slowing down the spread (Stage 2), and damage control (Stage 3). One key policy feature in Stage 2 and Stage 3 is based on "voluntary restriction”. It had a certain effect, but it was prolonged with each recurring "wave of infection”, resulting in economic exhaustion and people's dissatisfaction. Thus, the effect of the voluntary restriction has weakened, while the percentage of people who have been vaccinated is improving, making it difficult to predict the damage of the next "wave”. Under the hyper-aged society, it was necessary to identify and protect particularly vulnerable areas, i.e., psychiatry hospitals, chronic care hospitals, and long term care (LTC) facilities. On the other hand, secondary impacts extend to young people. The most serious one is the decrease in births which further accelerates the aging of society. Originality/value: This study is original as it investigated why Japan's unique countermeasures against COVID-19 without mandatory lockdown worked well for a considerable period. It also revealed that secondary impacts of the COVID-19 epidemic are broader and more significant than the direct loss of life, and that the social system, especially super-aged society with many vulnerable areas should be reformed in consideration of the threat of infectious diseases. Lessons from the Japanese case may contribute to other countries. © 2023, Tomonori Hasegawa, Koki Hirata and Kunichika Matsumoto.

Investigation of Treatment-Emergent Amino Acid Substitutions in Nonstructural Protein 5 from Ph2a Study of Ensitrelvir, a Novel Oral SARS-CoV-2 3C-Like Protease Inhibitor

Background. Ensitrelvir is a novel oral SARS-CoV-2 3C-like protease inhibitor, and under late clinical development stage for COVID-19 disease. In Ph2a and Ph2b studies, ensitrelvir demonstrated rapid decline of viral titer and viral RNA compared with placebo, and tolerability. To investigate treatment-emergent amino acid substitutions (TEAASs), we analyzed viral RNA sequences of nonstructural protein 5 (NSP5), target of ensitrelvir from Ph2a study in Japan. Methods. In Ph2a study, 69 patients with confirmed SARS-CoV-2 infection were randomized 1:1:1 to ensitrelvir with the loading dose on Day 1/maintenance dose on Day 2-5 (375/125 mg or 750/250 mg), or placebo. Intent-to-treat (ITT) population was defined as participants confirmed with positivity by qualitative RT-PCR at baseline. TEAASs were defined as novel amino acid substitutions identified after treatment with ensitrelvir. NSP5 sequence analysis was performed with sanger sequencing using nasopharyngeal swab samples at Day 1, 6, 9, 14, and 21 with allowances from ITT population with ensitrelvir. Infectious viral titer was measured by virus-induced cytopathic effects in VeroE6/TMPRSS2 cells. Viral RNA was quantified by RT-PCR. Results. By NSP5 sequence analysis, TEAASs were observed in 1 patient from 375/125 mg group and 2 patients from 750/250 mg group. H246Y in 375/125 mg was detected from specimen on Day 8, and A234S and T198I in 750/250 mg were detected from specimens on Day 8 and Day 14, respectively. Structural analysis revealed that these mutations are located outside of the active center of 3C-like protease which is the binding site of ensitrelvir. Viral titer and viral RNA in each specimen, in which TEAASs were observed, were below lower limit of detection and lower limit of quantification, respectively. Furthermore, H246Y, A234S and T198I are rare substitution (< 0.05%) among SARS-CoV-2 variants according to Global Initiative on Sharing Avian Influenza Data. Conclusion. In Ph2a study, H246Y, A234S, and T198I in NSP5 were detected as TEAASs. However, results of viral titer and viral RNA, and structural information suggest that these mutations do not have the impact on antiviral efficacy of ensitrelvir.

A Case of Silent COVID-19 Pneumonia Found by an Optional Chest CT Scan During a Health Check

We experienced a case of silent Coronavirus disease 2019 (COVID-19) pneumonia that was found by an optional chest computed tomography (CT) scan during a health check. A 62-year-old man with a present medical history of hypertension visited the health screening center at Tokai University Tokyo Hospital on August 7th, 2020. Prior to entry into the hospital, his body temperature was measured and his history was obtained (called 'COVID-19 triage'), but there were no remarkable findings. Subsequently, patchy ground glass opacities were observed with peripheral distribution in bilateral multiple lobes. Based on this finding COVID-19 pneumonia was highly suspected. Subsequently, a PCR test was positive for COVID-19. Even in health check settings, we should be aware of possible encounters with COVID-19 infections. The high risk of silent spread plays a significant role in the ongoing pandemic. Chest CT scans, which can efficiently identify silent COVID-19 pneumonia, should be performed earlier during health check examinations, at least before gastroendoscopy, which causes significant droplet dispersion. Health check examination providers should not cancel or postpone health checks;rather, it is necessary for them to provide health check examinees with a safe environment with minimal delay in access to recommended health care services.

A study of the effect of wearing face masks in preventing COVID-19 transmission in the United States of America

Purpose - The purpose of this paper is to intelligibly demonstrate the effectiveness of face mask wearing as a means to prevent COVID-19 transmission. Through understanding the benefits of wearing masks, it is hoped to facilitate the change of societal behavior and more people are willing to wear face mask. Design/methodology/approach - The paper investigates the 50 states in the United States of America (U.S.) and Washington, D.C. that implemented the mask mandates before September 30, 2020, which are divided into four groups: (1) those implemented the statewide mask mandates before June 5, 2020 when World Health Organization (WHO) recommended mask wearing;(2) those implemented statewide mask mandates after June 5, 2020;(3) those implemented partial mandates affecting 30 percent or more of the state's population;and (4) those implemented partial mandates affecting less than 30 percent. Simple descriptive statistics are analyzed. Findings - For the 50 U.S. states andWashington, D.C., the higher the mask wearing rate, the lower the number of COVID-19 cases (correlation coefficient: -0.69 (p<0.001)). For the 23 states with mobility reduction of less than 15 percent, the higher the proportion of population required to wear masks, the lower the number of cases. This can be seen from the difference in the number of cases among the four groups by ANOVA (p = 0.013). Originality - The positive effect of wearing masks is shown based on simple descriptive statistics for intuitive and intelligible understanding, which may lead people to comprehend the importance of wearing masks, and break through their custom, culture, and norms, and wear masks.

Faculty Survey on the Distance Learning of Engineering Education during the COVID-19

This work-in-progress paper describes a project of a faculty survey at our university about distance learning. The purpose is to assure the quality of distance learning. Therefore, we adopted a questionnaire survey for faculty-members in charge of classes. From the survey results, the attendance rate and the degree of understanding of distance learning were equitable or more to those of face-to-face learning. Faculty members also considered the communication environment and students with handicapped. Although there are some concerns, it makes clear that distance learning is conducted smoothly.