ImportanceDespite the COVID-19 pandemic’s effect on daily life, limited research exists on the prevalence and risk factors of suicidality and sadness among South Korean adolescents.ObjectivesTo examine whether the observed sadness and suicidality in the early to middle periods of the COVID-19 pandemic differed from the expected level and to investigate changes in risk factors for sadness and suicidality.Design, Setting, and ParticipantsThis nationwide serial cross-sectional survey study used data on 1 109 776 Korean adolescents aged 13 to 18 years from the Korea Youth Risk Behavior Web-based Survey from 2005 to 2021.ExposureThe COVID-19 pandemic.Main Outcomes and MeasuresThe pattern of changes in the percentage or proportion of sadness or suicidality, as well as the risk factors for sadness or suicidality. The transitional effect of the COVID-19 pandemic was assessed using weighted odds ratios (wORs) or weighted beta coefficients with 95% CIs.ResultsBetween 2005 and 2021, 1 109 776 adolescents (mean [SD] age, 15.0 [1.7] years; 51.5% male adolescents; and 51.7% in grades 7-9 and 48.3% in grades 10-12) were included in the Korea Youth Risk Behavior Web-based Survey. The slope of the long-term trends in sadness and suicidality decreased in the prepandemic period (sadness: from 37.8% [95% CI, 37.4%-38.2%] in 2005-2007 to 26.1% [95% CI, 25.9%-26.4%] in 2016-2019; suicidality: from 23.0% [95% CI, 22.7%-23.3%] in 2005-2007 to 12.3% [95% CI, 12.1%-12.5%] in 2016-2019), whereas the slope increased during the COVID-19 pandemic (sadness: from 25.0% [95% CI, 24.5%-25.6%] in 2020 to 26.6% [95% CI, 26.1%-27.1%] in 2021; trend difference in β, 0.249 [95% CI, 0.236-0.262]; suicidality: from 10.7% [95% CI, 10.3%-11.1%] in 2020 to 12.5% [95% CI, 12.1%-12.9%] in 2021; trend difference in β, 0.328 [95% CI, 0.312-0.344]). The trends presented a similar tendency in the subgroups according to sex, school grade, residential area, smoking status, and current alcohol use. Compared with the prepandemic period, the risk factors associated with sadness during the pandemic were younger age (wOR, 0.907; 95% CI, 0.881-0.933), female sex (wOR, 1.031; 95% CI, 1.001-1.062), urban residence (wOR, 1.120; 95% CI, 1.087-1.153), current smoking status (wOR, 1.134; 95% CI, 1.059-1.216), and current alcohol use (wOR, 1.051; 95% CI, 1.002-1.102). Female sex (wOR, 1.064; 95% CI, 1.021-1.109), urban residence (wOR, 1.117; 95% CI, 1.074-1.162), and low economic status (wOR, 1.286; 95% CI, 1.180-1.403) were the risk factors significantly associated with suicidality after the COVID-19 pandemic began.Conclusions and RelevanceIn this nationwide serial cross-sectional survey study of South Korean adolescents, the slope of the prevalence of sadness and suicidality increased during the COVID-19 pandemic after a decrease prior to the pandemic. The findings suggest that public health measures are needed to recognize vulnerable groups with risk factors and to prevent an increase in sadness and suicidality among adolescents during the COVID-19 pandemic.

Little is known about the ongoing monkeypox (mpox) outbreak, and the clinical features of mpox in patients worldwide have not been rigorously analysed. Thus, we aimed to investigate the clinical features associated with mpox infection and understand the pathophysiology and characteristics of the disease. For this systematic review and meta-analysis, we searched PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and the Cochrane Database of Systematic Reviews for articles published till 16 September 2022. We used a random effects model to calculate the pooled prevalence and 95% confidence interval (CI). We used the I 2 statistic to assess heterogeneity, Egger's test to assess publication bias, 95% prediction interval to determine the level of uncertainty, and the Newcastle-

Background Although previous studies have provided data on early pandemic periods of alcohol and substance use in adolescents, more adequate studies are needed to predict the trends of alcohol and substance use during recent periods, including the mid-pandemic period. This study investigated the changes in alcohol and substance use, except tobacco use, throughout the pre-, early-, and mid-pandemic periods in adolescents using a nationwide serial cross-sectional survey from South Korea. Methods Data on 1,109,776 Korean adolescents aged 13–18 years from 2005 to 2021 were obtained in a survey operated by the Korea Disease Control and Prevention Agency. We evaluated adolescents’ alcohol and substance consumption prevalence and compared the slope of alcohol and substance prevalence before and during the COVID-19 pandemic to see the trend changes. We define the pre-COVID-19 period as consisting of four groups of consecutive years (2005–2008, 2009–2012, 2013–2015, and 2016–2019). The COVID-19 pandemic period is composed of 2020 (early-pandemic era) and 2021 (mid-pandemic era). Results More than a million adolescents successfully met the inclusion criteria. The weighted prevalence of current alcohol use was 26.8% [95% confidence interval (CI) 26.4–27.1] from 2005 to 2008 and 10.5% (95% CI 10.1–11.0) in 2020 and 2021. The weighted prevalence of substance use was 1.1% (95% CI 1.1–1.2) from 2005 to 2008 and 0.7% (95% CI 0.6–0.7) between 2020 and 2021. From 2005 to 2021, the overall trend of use of both alcohol and drugs was found to decrease, but the decline has slowed since COVID-19 epidemic (current alcohol use: β diff 0.167; 95% CI 0.150–0.184; substance use: β diff 0.152; 95% CI 0.110–0.194). The changes in the slope of current alcohol and substance use showed a consistent slowdown with regard to sex, grade, residence area, and smoking status from 2005 to 2021. Conclusion The overall prevalence of alcohol consumption and substance use among over one million Korean adolescents from the early and mid-stage (2020–2021) of the COVID-19 pandemic showed a slower decline than expected given the increase during the prepandemic period (2005–2019). Supplementary Information The online version contains supplementary material available at 10.1007/s12519-023-00715-9.

Background Although smoking is classified as a risk factor for severe COVID-19 outcomes, there is a scarcity of studies on prevalence of smoking during the COVID-19 pandemic. Thus, this study aims to analyze the trends of prevalence of smoking in adolescents over the COVID-19 pandemic period. Methods The present study used data from middle to high school adolescents between 2005 and 2021 who participated in the Korea Youth Risk Behavior Web-based Survey (KYRBS). We evaluated the smoking prevalence (ever or daily) by year groups and estimated the slope in smoking prevalence before and during the pandemic. Results A total of 1,137,823 adolescents participated in the study [mean age, 15.04 years [95% confidence interval (CI) 15.03–15.06]; and male, 52.4% (95% CI 51.7–53.1)]. The prevalence of ever smokers was 27.7% (95% CI 27.3–28.1) between 2005 and 2008 but decreased to 9.8% (95% CI 9.3–10.3) in 2021. A consistent trend was found in daily smokers, as the estimates decreased from 5.4% (95% CI 5.2–5.6) between 2005 and 2008 to 2.3% (95% CI 2.1–2.5) in 2021. However, the downward slope in the overall prevalence of ever smokers and daily smokers became less pronounced in the COVID-19 pandemic period than in the pre-pandemic period. In the subgroup with substance use, the decreasing slope in daily smokers was significantly more pronounced during the pandemic than during the pre-pandemic period. Conclusions The proportion of ever smokers and daily smokers showed a less pronounced decreasing trend during the pandemic. The findings of our study provide an overall understanding of the pandemic’s impact on smoking prevalence in adolescents. Supplementary Information The online version contains supplementary material available at 10.1007/s12519-022-00673-8.

The monkeypox is an unusual viral disease which, until recently, has rarely been detected outside of Africa. Approximately over 70,000 laboratory-verified or suspected cases of human monkeypox have been discovered in at least 107 countries in a matter of months. A total of 71,237 laboratory confirmed cases, 1,097 probable cases, and 26 related deaths regarding the monkeypox were confirmed worldwide up to October 6th, 2022. Among the six World Health Organization regions, the Americas demonstrated the highest total laboratory-confirmed monkeypox cases (45,342 cases), followed by the European Region (24,889 cases), the African Region (727 cases), the Western Pacific Region (189 cases), the Eastern Mediterranean Region (67 cases), and the South-East Asia Region (23 cases). The nation with the highest cumulative monkeypox cases was the United States of America (26,723 cases), followed by Brazil (8,147 cases), Spain (7,209 cases), France (4,043 cases), The United Kingdom (3,654 cases), and Germany (3,640 cases). This international and comprehensive review, through analysis of the types and differences among the virus, the reason of its epidemic, and current available vaccines, aims to provide crucial information needed for monkeypox research and enhance global health policies in an individual-and country-level strategies towards the treatment of monkeypox.