As worldwide large-scale inoculation of novel vaccines is on the way, the importance of real-world data on safety cannot be overemphasized. We aimed to investigate the adverse events following immunization (AEFIs) associated with the ChAdOx1 nCoV-19 vaccine among healthcare workers (HCWs). We investigated the systemic and local adverse events reported within seven days following the first and second doses of vaccination, using the mobile vaccine adverse events reporting system (MVAERS) developed by our hospital. The response rates were 71.8% (994/1384) and 52.9% (727/1375) after the first and second doses, respectively. The most commonly reported AEFIs were tenderness and pain at the injection site and fatigue after the first and second doses. In comparison to the first dose, the incidence and severity of AEFIs were lower following the second dose. Since the Korean government does not recommend the ChAdOx1 nCoV-19 vaccination for those under 30 years of age, with greater risk than benefit, we additionally compared the AEFIs of age groups under and above 30 years of age. The overall incidence of AEFIs was similar in both the under and over 30 age groups. In conclusion, AEFIs associated with the ChAdOx1 nCoV-19 vaccine were found to be tolerable, and AEFIs associated with the second dose were less common and severe compared to the first dose. Further safety surveillance studies on COVID-19 vaccines are required to validate our findings.

Introduction: Vaccination is the most effective method of preventing infectious disease among healthcare workers (HCWs). Although HCWs are recommended to receive vaccination, the vaccination rates have been low. We sought to investigate the effect of HCWs’ vaccination recommendation program by the types of enforcement and influencing factors on compliance, with the aim of enhancing their immunity. Methodology: First and second interventions were carried out. During the first intervention, vaccinations were recommended through official documents. Hepatitis B vaccination was mandatory. Diphtheria toxoid, acellular pertussis (Tdap) and Hepatitis A vaccinations were recommended without financial support. MMR and varicella vaccinations were recommended with fees for the antibody test were covered by the hospital. One-to-one consultation (OC) regarding vaccination was held in the second intervention. Aside from the OC, the second intervention followed the same procedure as the first intervention for the antibody tests and vaccination, but differed in that pertussis vaccination fees were covered. Results: The immunization rates for infectious diseases were greater after the second intervention than the first intervention. The rate of immunized HCWs with hepatitis B virus was 100% at the end of the second intervention. The greatest increase in immunization rates from the first to the second intervention was that for pertussis, and the second greatest was that for hepatitis A. Age and working units were influencing factors on hepatitis A vaccine compliance. Conclusions: In order to increase vaccination rates, efforts must be made to deliver information to individual HCWs through OC as well as financial support including a mandatory policy.

Background/Objectives: Care-seeking for precocious puberty (PP) in South Korea has risen sharply, coinciding with dietary westernization among children. This study describes sex-specific and temporal dietary trends among Korean children aged 1–11 years, focusing on the 6–11-year band preceding the typical PP diagnosis threshold. Methods: Using KNHANES (2017–2021) dietary data and HIRA care-seeking counts with the sex-year aggregate, not the individual child. Sex differences were assessed using the Mann–Whitney U test, year-to-year patterns using a sex-by-year interaction model (n = 5 annual observations per sex), and dietary pattern structure using principal component analysis (PCA) on 12 food groups (n = 10 sex-year observations). Results: PP care-seeking rates rose in both sexes, substantially more in girls. Boys showed significantly higher intake of most food groups and macronutrients; within the 6–11-year band this held for meat, cola, and macronutrients (p = 0.008) but not legumes (p = 0.421). Macronutrient sex gaps numerically narrowed while meat and cola gaps widened over 2017–2021, though none reached significance. PCA identified a primary axis reflecting overall intake volume that separated boys and girls, and a secondary axis distinguishing a dairy/seaweed/beverage profile from a meat/egg/cola-dominant profile. Conclusions.: These findings describe sex-specific dietary patterns amid rising PP rates without establishing that intake volume explains the sex disparity, identifying candidate exposures for future research and cautioning against oversimplified dietary narratives.