Coronavirus disease 2019 (COVID-19) is a new infectious disease that has had a significant impact on daily life. This study investigated the effect of changes in family life due to COVID-19 on depressive mood and stress perception. We used data from the “Survey on changes in family life due to COVID-19” in Korea. The final study population comprised 1500 adults with children aged ≤19 years. Of the total respondents, 59.3% responded that depressive mood and stress had increased due to COVID-19. However, among them, 46.6% did not attempt to resolve or could not find a way to resolve their depressive mood and stress. In multiple logistic regression analyses, a decrease in household income and increased household expenditure due to COVID-19 were significantly associated with an increased risk of depressive mood and stress perception. Depressive mood and stress were significantly higher in respondents who answered that they had experienced family conflicts. These results could be used to assess changes in family life and manage mental health when a new infectious disease occurs. Therefore, it is necessary to assess the long-term effects of changes in family life due to COVID-19 on mental health.

This study aimed to determine whether secondhand smoking (SHS) in adolescents is associated with allergic diseases. Data from the 2019 Korea Youth Risk Behavior Survey were used (N = 37,848 Korean adolescents: 19,114 boys and 18,734 girls). This study assessed SHS exposure using questionnaire data, which included information, such as exposure to SHS and allergic diseases. Multiple logistic regression analysis was used to estimate the association between exposure to SHS and allergic diseases. The results showed that exposure to SHS in schools and public places, exposure for 1–3 days (OR = 1.158, 95% CI, 1.077–1.246), 4–6 days (OR = 1.308, 95% CI, 1.190–1.438), and everyday (OR = 1.306, 95% CI, 1.187–1.437), and exposure in one, two, or three places were significantly associated with allergic diseases (one OR = 1.226, 95% CI, 1.169–1.128, two OR = 1.289, 95% CI, 1.222–1.360 and three OR = 1.282, 95% CI, 1.177–1.395). The present results show that exposure to SHS occurs in various places and at various frequencies, and it is associated with allergic diseases in Korean adolescents.