Evaluation of Environmental Stability and Disinfectant Effectiveness for Human Coronavirus OC43 on Human Skin Surface.

The environmental stability of human coronavirus OC43 (HCoV-OC43) on the surface of human skin and the effectiveness of disinfectant against HCoV-OC43, which are important to prevent contact transmission, have not been clarified in previous studies. Using previously generated models, we evaluated HCoV-OC43 stability and disinfection effectiveness. Then we compared the results with those for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The median survival time of HCoV-OC43 on the surface of human skin was 24.6 h (95% confidence interval, 19.7 to 29.6 h), which was higher than that of SARS-CoV-2 (10.8 h). Although the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43 has a higher ethanol resistance than SARS-CoV-2, HCoV-OC43 on the skin surface was completely inactivated by a minimum of 50% ethanol within 5 s (the log reduction values were >4.0). Moreover, 1.0% chlorhexidine gluconate and 0.2% benzalkonium chloride showed relatively high disinfectant effectiveness, and the log reduction values when these disinfectants were applied for 15 s were >3.0. HCoV-OC43 is highly stable on the skin surface, which may increase the risk of contact transmission. Although HCoV-OC43 has relatively high ethanol resistance, appropriate hand hygiene practices with current alcohol-based disinfectants sufficiently reduce the risk of contact transmission. IMPORTANCE This study revealed the environmental stability of HCoV-OC43 and disinfectant effectiveness against HCoV-OC43, which had not been demonstrated in previous studies. HCoV-OC43 is highly stable on the surface of human skin, with a survival time of approximately 25 h. High stability of HCoV-OC43 may increase the risk of contact transmission. Furthermore, the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43, which is classified as an envelope virus, has a relatively high ethanol resistance. This finding suggests that disinfectant effectiveness may vary greatly depending on the virus and that each virus targeted for infection control should be evaluated individually. HCoV-OC43 on the skin surface was rapidly inactivated by 50% ethanol, which suggests that appropriate hand hygiene practices with current alcohol-based disinfectants can sufficiently reduce the risk of HCoV-OC43 contact transmission.

Discussion of the features of suicide trends in 1994-1995 and 2019-2020: The need for different contents in suicide prevention measures for both periods in Japan from the viewpoint of the present.

Japan is a country that is prone to natural disasters. This study compared the characteristics of suicide trends before and after the Great Hanshin-Awaji Earthquake, and during the current COVID-19 pandemic 25 years later. In the present study, we examined the annual number of suicides, the number of suicides by age group, and the reason for suicide during the period associated with the earthquake (1994-1995) and the period associated with the pandemic (2019-2020). This study used statistical analyses to compare the two periods. Our findings suggest that research needs to be conducted from the perspective of legal medicine and social medicine to devise current and future measures to prevent suicides. During the first period, suicides increased in 1995 compared to 1994. Suicide due to economic and life problems increased significantly. During the second period, suicides increased in 2020 compared to 2019. Suicides by males decreased significantly and those by females increased significantly; suicides by individuals aged 19 or under and by those aged 20-29 increased significantly, while suicides by individuals aged 60-69 decreased significantly; and suicides due to "other problems" increased significantly, while suicides due to economic and life problems decreased significantly. Ongoing studies of detailed trends in suicides due to the effects of COVID-19 need to be conducted in the future, and it is important to determine suicide risk due to the effects of COVID-19. Legal medicine and social medicine are fields that conduct such studies and that can offer science-based responses to these trends.

Changes in university classes as COVID-19 continues and new findings regarding future university instruction methods: from the perspective of Japan and Semey, Republic of Kazakhstan.

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Adequate measures to prevent medical personnel from contracting COVID-19 should be promptly implemented: support from numerous agencies is needed.

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A case of urgent colonoscopic hemostasis of a cecal hemorrhagic ulceration in a patient receiving heparin for COVID-19 coagulopathy.

COVID-19 rarely causes lower gastrointestinal bleeding even though its RNA has been detected in patient's stool. Urgent colonoscopy in a COVID-19 patient with massive bloody stool requires various procedural and equipment considerations. Here, we present a case of colonoscopic hemostasis of a cecal hemorrhagic ulceration in a patient on heparin for COVID-19 coagulopathy. We also share various management methods for the prevention of COVID-19 contamination. A 71-year-old man was diagnosed with COVID-19 pneumonia and subsequently underwent hemodiafiltration. Heparin was initiated for COVID-19 coagulopathy. At day 42, the patient experienced 2000 mL of bloody stool. An operator performed urgent colonoscopy with three assistants in a negative-pressure room with full personal protective equipment. A hemorrhagic ulceration was detected at the cecum, and endoscopic hemostasis was performed. Immunohistochemistry was positive for cytomegalovirus. Postprocedure, the endoscopic systems were thoroughly cleaned, and specific measures for endoscope reprocessing and disinfection were performed to prevent contamination with COVID-19.