Singing Is a Risk Factor for Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Case-Control Study of Karaoke-Related Coronavirus Disease 2019 Outbreaks in 2 Cities in Hokkaido, Japan, Linked by Whole Genome Analysis.

Background: Singing in an indoor space may increase the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We conducted a case-control study of karaoke-related coronavirus disease 2019 (COVID-19) outbreaks to reveal the risk factors for SARS-CoV-2 infection among individuals who participate in karaoke. Methods: Cases were defined as people who enjoyed karaoke at a bar and who tested positive for SARS-CoV-2 by reverse-transcription polymerase chain reaction between 16 May and 3 July 2020. Controls were defined as people who enjoyed karaoke at the same bar during the same period as the cases and tested negative. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. ORs of key variables adjusted for each other were also estimated (aOR). Results: We identified 81 cases, the majority of whom were active elderly individuals (median age, 75 years). Six cases died (case fatality ratio, 7%). Among the cases, 68 (84%) were guests, 18 of whom had visited ≧2 karaoke bars. A genome analysis conducted in 30 cases showed 6 types of isolates within 4 single-nucleotide variation difference. The case-control study revealed that singing (aOR, 11.0 [95% CI, 1.2-101.0]), not wearing a mask (aOR, 3.7 [95% CI, 1.2-11.2]), and additional hour spent per visit (aOR, 1.7 [95% CI, 1.1-2.7]) were associated with COVID-19 infection. Conclusions: A karaoke-related COVID-19 outbreak that occurred in 2 different cities was confirmed by the results of genome analysis. Singing in less-ventilated, indoor and crowded environments increases the risk of acquiring SARS-CoV-2 infection. Wearing a mask and staying for only a short time can reduce the risk of infection during karaoke.

[Association between clustered strain of M. tuberculosis and infectiousness index of tuberculosis cases in a population-based IS6110-RFLP analysis].

OBJECTIVE: Isolates of M. tuberculosis were analyzed for their DNA fingerprints to facilitate understanding of ongoing transmission of tuberculosis in Sapporo (population 1.87 million), Japan, where the incidence rate of tuberculosis was 15.0 per 100,000 in 2004. SUBJECT: Out of all tuberculosis patients registered in the city from November 1998 to December 2003, isolates from culture-positive respiratory tuberculosis cases for whom written informed consent had been obtained, were analyzed by restriction fragment length polymorphism (RFLP). The study included 345 cases (249 men and 96 women) whose isolates were available for DNA patterns. METHOD: Using standard IS6110-RFLP typing, cases whose isolates shared identical fingerprints were considered to belong to the same cluster. Proportions of clustered cases were evaluated according to their clinical and socio-economical characteristics. RESULTS: Out of 345 cases, 207 (60.0%) were classified into 59 clusters, and 15% of clustered cases having definite epidemiological links. Multiple logistic regression analysis in men showed that age and infectiousness were significantly related to clustering. The adjusted odds ratios (OR) [95% confidence intervals (CI)] were 0.17 [0.03-0.79] for 30-59 years, 0.15 [0.03-0.69] for 60 years or over and 2.35 [1.17-4.70] for those cases assigned as the highest level of transmission of tuberculosis from the infectiousness index of cases. For women the final model showed the adjusted OR [95% CI] were 0.52 [0.22-1.22] for those with previous history of tuberculosis and 0.33 [0.06-1.85] for diabetics. In male cases with a previous history of tuberculosis, most highly infectious cases were significantly associated with clustering (OR [95% CI], 4.53 [1.16-17.68]). CONCLUSION: The results suggest that highly infectious male tuberculosis cases with endogenous reactivation have contributed to recent transmission of tuberculosis in the studied area.

[Study of influences of social support and social networks on participation in periodic health examination of the elderly at home comparison of three regions with different social backgrounds].

PURPOSE: Periodic health examination are presumed to be important with respect to the well-being of aged individuals. The purpose of this study was to analyze the relationships between elderly at home accepting periodic health examination and their social support and social networks. METHOD: The survey was performed targeting so-called young elderly persons living at home in 3 regions in Hokkaido Prefecture, a large city (Sapporo), an ex-coalmining town (Yuubari) and a small farming town (Takasu). The study populations were asked about social support and social networks, and the Mantel-Haenszel method was applied to analyze the data. RESULTS: 1) Both males and females who received periodic health examination within the last one year (participants) were members of various groups, such as neighborhood societies, clubs for the elderly and so on, and were more interested in public magazines and political issues than those who had never received periodic health examination (non-participants). Elderly males who accepted periodic health examination were those who were interested in elections, who had a hobby, and who thought that life was worthwhile. 2) Both elderly males and females who accepted periodic health examination were those who had friends, and elderly males who accepted periodic health examination were those who had close relatives and who lived in a friendly neighborhood. 3) Elderly males who accepted periodic health examination were more likely to both receive and supply instrumental and emotional support in interaction with others.

[Tuberculin skin test reaction of health-care workers exposed to tuberculosis infection].

OBJECTIVE: The objective of this study was to describe tuberculin skin test (TST) of health-care workers who had had contacts with a tuberculosis patient and to investigate whether the distributions of the size of TST were different by sputum-smear status of index cases and medical procedures done to the patient. SUBJECTS: Health-care workers who were exposed to tuberculosis infection through contact with patients before diagnosis of tuberculosis were included in this study. Index cases had pulmonary tuberculosis with positive sputum smear and were registered at Sapporo Public Health Office from April 2001 to March 2002. Subjects without past history of BCG (bacilli Calmette-Guerin) vaccinacion were excluded, and final study subjects were 415 (52 male and 363 female, mean age 29.1 years). METHOD: Characteristics of index cases and contact status were obtained from the registration cards of tuberculosis cases at Sapporo Public Health Office. Subjects were divided into two or more categories by the characteristics of index cases and the contact status. Distributions of TST of the subjects in different categories were compared. RESULTS: Contacts with patients received tracheal aspiration showed significantly larger TST reaction than contacts with patients not receiving tracheal aspiration. Among contacts with patients showing minimum to moderately positive sputum-smear, TST reaction was significantly larger in contacts with patients received tracheal aspiration (mean diameter of erythema 35.8 mm) than those not receiving tracheal aspiration (24.8 mm). In contrast, among contacts with patients of severely positive sputum-smear, TST reaction was not significantly different between contacts of patients received tracheal aspiration (35.3 mm) and not receiving tracheal aspiration (33.1 mm). CONCLUSION: TST was significantly stronger in contacts with a tuberculosis patient received tracheal aspiration, which indicates medical procedures such as tracheal aspiration increases the risk of tuberculosis infection in health-care workers.

[Factors associated with participation in medical checkups of the elderly at home comparison of 3 regions with different social backgrounds].

PURPOSE: Annual medical checkups are presumed to be important with the well-being of aged individuals. The purpose of this study was to investigate factors related to participation in medical checkups of elderly persons at home. METHODS: A survey was performed targeting so-called young elderly persons living at home in 3 regions in Hokkaido Prefecture, a large city (Sapporo), an ex-coalmining town (Yubari) and a small farming town (Takasu). The study populations were asked about medical checkups, economic status, self-rated health status, activities of daily living (ADL) and basic characteristics such as age, sex and occupation. We used the Mantel-Haenszel method for statistical analysis. RESULTS: 1) Elderly males who received medical checkups within the last 1 year (participants) had a shorter period of education, were less likely to have or to have had the smoking habit, undertook more physical activity, had better eating habit, more often rated their own health as good or normal, and had a better physical ADL & instrumental ADL, than those who had never received medical checkups (non-participants). Regionally, the items that showed significant differences included: "live with the spouse", "do not smoke" and "do not have physical pain or disabilities" in Sapporo; "enjoy physical activity", "have good eating habit" and "have good instrumental ADL" in Yubari; and "engaged in agriculture/fishery work" and "had outpatient visits in the last three months" in Takasu. 2) Elderly female participants who had outpatient visits in the last three months had anxiety about their own health, significantly different from non-participants. Regionally, the items that showed significant differences included: "often drink alcohol" in Sapporo; "still working right now", "was engaged in agriculture/fishery work in the past" and "had outpatient visits in the last three months" in Yubari; and "have own house", "do not smoke" and "pay attention to eating habit" in Takasu. 3) The item which showed a significantly high rate both for male and female participants was "still working right now". CONCLUSIONS: This study indicates that medical checkups should be recommended to the elderly, taking into account not only their basic characteristics such as sex and occupation, but also lifestyle, self-rated health status and ADL, which are associated with medical checkup participation.