The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new zoonotic agent that emerged in December 2019, causes coronavirus disease 2019 (COVID-19). This infection can be spread by asymptomatic, presymptomatic, and symptomatic carriers. SARS-CoV-2 spreads primarily via respiratory droplets during close person-to-person contact in a closed space, especially a building. This article summarizes the environmental factors involved in SARS-CoV-2 transmission, including a strategy to prevent SARS-CoV-2 transmission in a building environment. SARS-CoV-2 can persist on surfaces of fomites for at least 3 days depending on the conditions. If SARS-CoV-2 is aerosolized intentionally, it is stable for at least several hours. SARS-CoV-2 is inactivated rapidly on surfaces with sunlight. Close-contact aerosol transmission through smaller aerosolized particles is likely to be combined with respiratory droplets and contact transmission in a confined, crowded, and poorly ventilated indoor environment, as suggested by some cluster cases. Although evidence of the effect of aerosol transmission is limited and uncertainty remains, adequate preventive measures to control indoor environmental quality are required, based on a precautionary approach, because COVID-19 has caused serious global damages to public health, community, and the social economy. The expert panel for COVID-19 in Japan has focused on the "3 Cs," namely, "closed spaces with poor ventilation," "crowded spaces with many people," and "close contact." In addition, the Ministry of Health, Labour and Welfare of Japan has been recommending adequate ventilation in all closed spaces in accordance with the existing standards of the Law for Maintenance of Sanitation in Buildings as one of the initial political actions to prevent the spread of COVID-19. However, specific standards for indoor environmental quality control have not been recommended and many scientific uncertainties remain regarding the infection dynamics and mode of SARS-CoV-2 transmission in closed indoor spaces. Further research and evaluation are required regarding the effect and role of indoor environmental quality control, especially ventilation.
Aerosols ; Air Pollution, Indoor/prevention & control* ; Betacoronavirus/physiology* ; COVID-19 ; Coronavirus Infections/transmission* ; Crowding ; Environment, Controlled ; Humans ; Pandemics/prevention & control* ; Pneumonia, Viral/transmission* ; SARS-CoV-2 ; Ventilation

Microorganisms play important roles in obesity; however, the role of the gut microbiomes in obesity is controversial because of the inconsistent findings. This study investigated the gut microbiome communities in obese and lean groups of captive healthy cynomolgus monkeys reared under strict identical environmental conditions, including their diet. No significant differences in the relative abundance of Firmicutes, Bacteroidetes and Prevotella were observed between the obese and lean groups, but a significant difference in Spirochetes (p < 0.05) was noted. Microbial diversity and richness were similar, but highly variable results in microbial composition, diversity, and richness were observed in individuals, irrespective of their state of obesity. Distinct clustering between the groups was not observed by principal coordinate analysis using an unweighted pair group method. Higher sharedness values (95.81% ± 2.28% at the genus level, and 79.54% ± 5.88% at the species level) were identified among individual monkeys. This paper reports the association between the gut microbiome and obesity in captive non-human primate models reared under controlled environments. The relative proportion of Firmicutes and Bacteroidetes as well as the microbial diversity known to affect obesity were similar in the obese and lean groups of monkeys reared under identical conditions. Therefore, obesity-associated microbial changes reported previously appear to be associated directly with environmental factors, particularly diet, rather than obesity.
Bacteroidetes ; Diet ; Environment, Controlled ; Firmicutes ; Gastrointestinal Microbiome ; Haplorhini ; Macaca fascicularis ; Methods ; Microbiota ; Obesity ; Prevotella ; Primates ; Spirochaetales

BACKGROUND: The aim of this study was to describe the types of diseases that developed in semiconductor workers who have registered with the Korea Workers' Compensation and Welfare Service (KWCWS) and to identify potential common occupational characteristics by the type of claimed disease. METHODS: A total of 55 semiconductor workers with cancer or rare diseases who claimed to the KWCWS were compared based on their work characteristics and types of claimed diseases. Leukemia, non-Hodgkin lymphoma, and aplastic anemia were grouped into lymphohematopoietic (LHP) disorder. RESULTS: Leukemia (n = 14) and breast cancer (n = 10) were the most common complaints, followed by brain cancer (n = 6), aplastic anemia (n = 6), and non-Hodgkin lymphoma (n = 4). LHP disorders (n = 24) accounted for 43%. Sixty percent (n = 33) of registered workers (n = 55) were found to have been employed before 2000. Seventy-six percent (n = 42) of registered workers and 79% (n = 19) among the registered workers with LHP (n = 24) were found to be diagnosed at a relatively young age, ≤40 years. A total of 18 workers among the registered semiconductor workers were finally determined to deserve compensation for occupational disease by either the KWCWS (n = 10) or the administrative court (n = 8). Eleven fabrication workers who were compensated responded as having handled wafers smaller than eight inches in size. Eight among the 18 workers compensated (44 %) were found to have ever worked at etching operations. CONCLUSION: The distribution of cancer and rare diseases among registered semiconductor workers was closely related to the manufacturing era before 2005, ≤8 inches of wafer size handled, exposure to clean rooms of fabrication and chip assembly operations, and etching operations.
Anemia, Aplastic ; Brain Neoplasms ; Breast Neoplasms ; Compensation and Redress ; Environment, Controlled ; Korea ; Leukemia ; Lymphoma, Non-Hodgkin ; Occupational Diseases ; Rare Diseases ; Semiconductors ; Workers' Compensation

The incidence of obesity has been rapidly increasing, and this condition has become a major public health threat. A substantial shift in environmental factors and lifestyle, such as unhealthy diet, is among the major driving forces of the global obesity pandemic. Longitudinal studies and randomized intervention trials have shown that genetic susceptibility to obesity may interact with dietary factors in relation to the body mass index and risk of obesity. This review summarized data from recent longitudinal studies and intervention studies on variations and diets and discussed the challenges and future prospects related to this area and public health implications.
Body Mass Index ; Diet ; Gene-Environment Interaction ; Genetic Predisposition to Disease ; Humans ; Life Style ; Obesity ; epidemiology ; genetics ; Observational Studies as Topic ; Randomized Controlled Trials as Topic

Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.
Delivery of Health Care ; Environment, Controlled ; Filtration ; Humans ; Infection Control* ; Personal Protective Equipment ; Tuberculosis* ; Ventilation ; Ventilators, Mechanical

To determine the correlation between the working environment and the health status of employees in solar greenhouse, 1171 employees were surveyed. The results show the 'Greenhouse diseases' are affected by many factors. Among general uncomforts, the morbidity of the bone and joint damage is the highest and closely related to labor time and age. Planting summer squash and wax gourd more easily cause skin pruritus. Asthma-related cough, eye disease, and skin pruritus are significantly correlated with the cultivation of wax gourd. The application of inorganic fertilizer and fertigation dramatically induce the bone and joint damage. The smell of covering film greatly influence skin pruritus. Personal protection is badly scanty and normative occupational health and safety need to be completed.
Adult ; Asthma ; chemically induced ; Cough ; chemically induced ; Crops, Agricultural ; Educational Status ; Environment, Controlled ; Eye Diseases ; chemically induced ; Fertilizers ; toxicity ; Humans ; Middle Aged ; Nose Diseases ; chemically induced ; Occupational Exposure ; Pesticides ; toxicity ; Pruritus ; chemically induced ; Risk Factors ; Stomach Diseases ; chemically induced ; Workplace

PURPOSE: The study aimed to compare the physical activity of hematopoietic stem cell transplantation (HSCT) patients with healthy people (HP). METHODS: The research design of this study was cross sectional and, descriptive study. It was conducted from January 26th to May 22nd, 2013. We matched HSCT patients to HP based on age and gender, and measured physical activity using a pedometer. Patient's clinical information were gathered by the medical record reviews. RESULTS: The number of steps was significantly less in HSCT patients (HSCT: 214 (7~3,373) vs HP: 7,921 (3,180~17,539), p<.001). Physical activity time was significantly less in HSCT patients (HSCT: 840 (680~1,320)min vs HP: 990 (540~1,090)min, p<.001). Step count showed a significant relationship with platelet count (r=.40, p=.004). CONCLUSION: HSCT patients perform very low intensity of physical activities. The study shows the necessity to apply programs to promote physical activities in isolation rooms for patients undergoing HSCT.
Environment, Controlled ; Exercise Test ; Hematologic Diseases ; Hematopoietic Stem Cell Transplantation* ; Humans ; Medical Records ; Motor Activity* ; Platelet Count ; Research Design

OBJECTIVE: To measure the prevalence of dry eye syndrome (DES) among clean room (relative humidity < or =1%) workers from 2011 to 2013. METHODS: Three annual DES examinations were performed completely in 352 clean room workers aged 20-40 years who were working at a secondary battery factory. Each examination comprised the tear-film break-up test (TFBUT), Schirmer's test I, slit-lamp microscopic examination, and McMonnies questionnaire. DES grades were measured using the Delphi approach. The annual examination results were analyzed using a general linear model and post-hoc analysis with repeated-ANOVA (Tukey). Multiple logistic regression was performed using the examination results from 2013 (dependent variable) to analyze the effect of years spent working in the clean room (independent variable). RESULTS: The prevalence of DES among these workers was 14.8% in 2011, 27.1% in 2012, and 32.8% in 2013. The TFBUT and McMonnies questionnaire showed that DES grades worsened over time. Multiple logistic regression analysis indicated that the odds ratio for having dry eyes was 1.130 (95% CI 1.012-1.262) according to the findings of the McMonnies questionnaire. CONCLUSIONS: This 3-year trend suggests that the increased prevalence of DES was associated with longer working hours. To decrease the prevalence of DES, employees should be assigned reasonable working hours with shift assignments that include appropriate break times. Workers should also wear protective eyewear, subdivide their working process to minimize exposure, and utilize preservative-free eye drops.
Dry Eye Syndromes* ; Environment, Controlled* ; Humidity ; Linear Models ; Logistic Models ; Odds Ratio ; Ophthalmic Solutions ; Prevalence*

PURPOSE: To determine the change in lacrimal gland (LG) acinar cells induced by in vivo dry eye (DE). METHODS: Six to 8-week-old (C57BL/6) mice were placed in a controlled environment chamber at <20% humidity for 2 weeks, and a control group was bred in a normal environment. After these 2 weeks of dry eye (DE) induction, the mice were sacrificed and their LGs were collected. Lacrimal gland acinar cell organelle structures were observed with Transmission Electron Microscopy (TEM). TEM images were analyzed using the Image J program. RESULTS: The size of the LGs of DE-induced mice decreased compared to those of normal mice. Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) staining was negative in DE-induced LGs. Under the TEM, the endoplasmic reticulum (ER) lumen was dilated and the lumen density increased in DE-induced mice. Additionally, cell organelles were surrounded by elongated ER lumens. The mitochondrial structure was destroyed and the number of vacuoles increased in the LGs of DE-induced mice. CONCLUSIONS: Structural changes of the LG developed due to DE induction. This suggests that the detailed mechanisms of these changes were ER stress and autophagy. However, there were no definite signs of apoptosis in the acinar cells of the DE-induced LGs. These findings are regarded as an important clue of the pathogenesis of non-Sjogren-type dry eye.
Acinar Cells* ; Animals ; Apoptosis ; Autophagy ; DNA Nucleotidylexotransferase ; Endoplasmic Reticulum ; Environment, Controlled ; Humidity ; Lacrimal Apparatus* ; Mice ; Microscopy, Electron, Transmission ; Organelles ; Vacuoles

Oxygen enrichment of room air is an effective way to resist hypoxia at high altitude, but it may introduce a potential fire hazard. In common, the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere was used to assess the fire hazard. For the purpose of measuring the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere, we used the methods of laser contact ignition and direct calculation of burning rate, and invented a device that includes mixing gas system, ignition equipment, system of measuring the burning rate and self-made specimen frame. By using the homemade device, we studied the burning rate of filter paper under low pressure and in oxygen-enriched atmosphere and in that of the oxygen concentration of reached stationary burning rate. The results showed that this device was simple, and could obtain the burning rate of light and thin homogeneous solid quantitatively.
Air Pressure ; Altitude ; Atmosphere Exposure Chambers ; Environment, Controlled ; Equipment Design ; Fires ; prevention & control ; Oxygen ; analysis