The emergence of the omicron variant and its sub-lineages has necessitated vaccine updates for coronavirus disease 2019. In September 2023, the U.S. Food and Drug Administration approved an updated BNT162b2 vaccine targeting the omicron XBB.1.5 variant, which was initiated in Korea in October 2024. This study demonstrates the adverse events reported through active nationwide surveillance after XBB.1.5 vaccination in Korea. Since October 19, 2023, the Korea Disease Control and Prevention Agency has conducted daily Short Message Service surveys to collect data on health issues, fever, vaccination site reactions, systemic symptoms, impact on daily life, and healthcare visits. Among 20,180 respondents, 27.9% reported health issues. Adverse reactions peaked on day 1 (28.7%), including pain at the vaccination site, muscle pain, fatigue, and fever. These findings elucidate the short-term safety of the XBB.1.5 vaccine and support its co-administration with the influenza vaccine, reducing vaccine hesitancy and achieving herd immunity.

The emergence of the omicron variant and its sub-lineages has necessitated vaccine updates for coronavirus disease 2019. In September 2023, the U.S. Food and Drug Administration approved an updated BNT162b2 vaccine targeting the omicron XBB.1.5 variant, which was initiated in Korea in October 2024. This study demonstrates the adverse events reported through active nationwide surveillance after XBB.1.5 vaccination in Korea. Since October 19, 2023, the Korea Disease Control and Prevention Agency has conducted daily Short Message Service surveys to collect data on health issues, fever, vaccination site reactions, systemic symptoms, impact on daily life, and healthcare visits. Among 20,180 respondents, 27.9% reported health issues. Adverse reactions peaked on day 1 (28.7%), including pain at the vaccination site, muscle pain, fatigue, and fever. These findings elucidate the short-term safety of the XBB.1.5 vaccine and support its co-administration with the influenza vaccine, reducing vaccine hesitancy and achieving herd immunity.

In response to the Mpox domestic epidemic, South Korea initiated a nationwide vaccination program in May 2023, administering a 0.1 mL intradermal dose of JYNNEOS (Modified Vaccinia Ankara vaccine, Bavarian Nordic) to a high-risk group. To investigate the adverse reactions after intradermal JYNNEOS vaccination, an anonymous online survey was conducted at the National Medical Center from May 22 to July 31, 2023. Overall, 142 individuals responded. Over 80% of the respondents reported local reactions of predominantly mild severity. The predominant local reactions were pruritus, redness, and swelling; their incidence rates after the first dose were 66.2%, 48.1%, and 49.4%, respectively; the corresponding rates after the second dose were 69.2%, 60.6%, and 53.8%. Fewer respondents reported systemic symptoms. The most common systemic symptom was fatigue, the incidence rates of which after the first and second doses were 37.7% and 24.6%, respectively. Overall, the intradermally administered JYNNEOS vaccine appeared well tolerated.

We aimed to characterize the genomes of monkeypox virus isolates from the Far East, providing insights into viral transmission and evolution. Genomic analysis was conducted on 8 isolates obtained from patients with monkeypox virus disease in the Republic of Korea between May 2022 and early 2023. These isolates were classified into Clade IIb. Distinct lineages, including B.1.1, A.2.1, and B.1.3, were observed in 2022 and 2023 isolates, with only the B.1.3 lineage detected in six isolates of 2023. These genetic features were specific to Far East isolates (the Republic of Korea, Japan, and Taiwan), distinguishing them from the diverse lineages found in the Americas, Europe, Africa, and Oceania. In early 2023, the prevalence of the B.1.3 lineage of monkeypox virus identified in six patients with no overseas travel history is considered as an indicator of the potential initiation of local transmission in the Republic of Korea.

Background: Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) can cause more rapid progression to cirrhosis than HCV-monoinfection. In this study, incident HCV case (IHCV)s were investigated in a HIV clinic in Korea. Materials and Methods: A retrospective HIV cohort was constructed who visited National Medical Center in Korea from 2013 to 2022 and performed ≥ 1 anti-HCV antibody tests (anti-HCV) during the study period. IHCV was defined as newly confirmed HCV infection by PCR with a prior negative anti-HCV and factors associated with IHCV were investigated among alanine aminotransferase (ALT) >150 IU/mL sub-cohort without plausible reasons for ALT elevation. Results: Overall, 2,567 HIV clinic visitors were recruited during the study period and 42 (1.63%) were confirmed as HIV/HCV co-infection. Fifteen IHCVs were identified during the study period. While no IHCV was observed in 2013–2015, incidence of 2016–2019 and 2020–2022 were 0.84 and 1.48 per 1000 person-year, respectively. Subtype 1a were more common among IHCVs in 2020–2022 (8/9) while subtype 2 dominated in 2016–2019 (5/6, P=0.003). Most IHCVs were identified during the evaluation of de novo liver enzyme elevation which was identified through the regularly performed blood tests (86.7%, 13/15). Comparing twelve IHCVs with ALT>150 IU/mL with 58 HIV mono-infection comparators whose peak ALT exceeded 150 IU/mL during the study period, age, sex, HIV/HCV infection risk factor, CD4 cell count, and HIV-RNA viral load were not different between two groups. However, mean peak ALT of IHCVs was higher than comparators (776 vs. 237, P<0.001) and syphilis treatment within prior 24 months of ALT elevation was more common in IHCV group (41.7% vs. 12.7%, P=0.026). Conclusion Incidence rate of HCV among PLH revealed increasing trend between 2013 and 2022 among visitors at a HIV clinic in Korea. Subtype 1a dominated among IHCVs after 2020 and recent syphilis treatment was associated with IHCVs.

Background: Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) can cause more rapid progression to cirrhosis than HCV-monoinfection. In this study, incident HCV case (IHCV)s were investigated in a HIV clinic in Korea. Materials and Methods: A retrospective HIV cohort was constructed who visited National Medical Center in Korea from 2013 to 2022 and performed ≥ 1 anti-HCV antibody tests (anti-HCV) during the study period. IHCV was defined as newly confirmed HCV infection by PCR with a prior negative anti-HCV and factors associated with IHCV were investigated among alanine aminotransferase (ALT) >150 IU/mL sub-cohort without plausible reasons for ALT elevation. Results: Overall, 2,567 HIV clinic visitors were recruited during the study period and 42 (1.63%) were confirmed as HIV/HCV co-infection. Fifteen IHCVs were identified during the study period. While no IHCV was observed in 2013–2015, incidence of 2016–2019 and 2020–2022 were 0.84 and 1.48 per 1000 person-year, respectively. Subtype 1a were more common among IHCVs in 2020–2022 (8/9) while subtype 2 dominated in 2016–2019 (5/6, P=0.003). Most IHCVs were identified during the evaluation of de novo liver enzyme elevation which was identified through the regularly performed blood tests (86.7%, 13/15). Comparing twelve IHCVs with ALT>150 IU/mL with 58 HIV mono-infection comparators whose peak ALT exceeded 150 IU/mL during the study period, age, sex, HIV/HCV infection risk factor, CD4 cell count, and HIV-RNA viral load were not different between two groups. However, mean peak ALT of IHCVs was higher than comparators (776 vs. 237, P<0.001) and syphilis treatment within prior 24 months of ALT elevation was more common in IHCV group (41.7% vs. 12.7%, P=0.026). Conclusion Incidence rate of HCV among PLH revealed increasing trend between 2013 and 2022 among visitors at a HIV clinic in Korea. Subtype 1a dominated among IHCVs after 2020 and recent syphilis treatment was associated with IHCVs.

The emergence of the omicron variant and its sub-lineages has necessitated vaccine updates for coronavirus disease 2019. In September 2023, the U.S. Food and Drug Administration approved an updated BNT162b2 vaccine targeting the omicron XBB.1.5 variant, which was initiated in Korea in October 2024. This study demonstrates the adverse events reported through active nationwide surveillance after XBB.1.5 vaccination in Korea. Since October 19, 2023, the Korea Disease Control and Prevention Agency has conducted daily Short Message Service surveys to collect data on health issues, fever, vaccination site reactions, systemic symptoms, impact on daily life, and healthcare visits. Among 20,180 respondents, 27.9% reported health issues. Adverse reactions peaked on day 1 (28.7%), including pain at the vaccination site, muscle pain, fatigue, and fever. These findings elucidate the short-term safety of the XBB.1.5 vaccine and support its co-administration with the influenza vaccine, reducing vaccine hesitancy and achieving herd immunity.

Background: Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) can cause more rapid progression to cirrhosis than HCV-monoinfection. In this study, incident HCV case (IHCV)s were investigated in a HIV clinic in Korea. Materials and Methods: A retrospective HIV cohort was constructed who visited National Medical Center in Korea from 2013 to 2022 and performed ≥ 1 anti-HCV antibody tests (anti-HCV) during the study period. IHCV was defined as newly confirmed HCV infection by PCR with a prior negative anti-HCV and factors associated with IHCV were investigated among alanine aminotransferase (ALT) >150 IU/mL sub-cohort without plausible reasons for ALT elevation. Results: Overall, 2,567 HIV clinic visitors were recruited during the study period and 42 (1.63%) were confirmed as HIV/HCV co-infection. Fifteen IHCVs were identified during the study period. While no IHCV was observed in 2013–2015, incidence of 2016–2019 and 2020–2022 were 0.84 and 1.48 per 1000 person-year, respectively. Subtype 1a were more common among IHCVs in 2020–2022 (8/9) while subtype 2 dominated in 2016–2019 (5/6, P=0.003). Most IHCVs were identified during the evaluation of de novo liver enzyme elevation which was identified through the regularly performed blood tests (86.7%, 13/15). Comparing twelve IHCVs with ALT>150 IU/mL with 58 HIV mono-infection comparators whose peak ALT exceeded 150 IU/mL during the study period, age, sex, HIV/HCV infection risk factor, CD4 cell count, and HIV-RNA viral load were not different between two groups. However, mean peak ALT of IHCVs was higher than comparators (776 vs. 237, P<0.001) and syphilis treatment within prior 24 months of ALT elevation was more common in IHCV group (41.7% vs. 12.7%, P=0.026). Conclusion Incidence rate of HCV among PLH revealed increasing trend between 2013 and 2022 among visitors at a HIV clinic in Korea. Subtype 1a dominated among IHCVs after 2020 and recent syphilis treatment was associated with IHCVs.

The emergence of the omicron variant and its sub-lineages has necessitated vaccine updates for coronavirus disease 2019. In September 2023, the U.S. Food and Drug Administration approved an updated BNT162b2 vaccine targeting the omicron XBB.1.5 variant, which was initiated in Korea in October 2024. This study demonstrates the adverse events reported through active nationwide surveillance after XBB.1.5 vaccination in Korea. Since October 19, 2023, the Korea Disease Control and Prevention Agency has conducted daily Short Message Service surveys to collect data on health issues, fever, vaccination site reactions, systemic symptoms, impact on daily life, and healthcare visits. Among 20,180 respondents, 27.9% reported health issues. Adverse reactions peaked on day 1 (28.7%), including pain at the vaccination site, muscle pain, fatigue, and fever. These findings elucidate the short-term safety of the XBB.1.5 vaccine and support its co-administration with the influenza vaccine, reducing vaccine hesitancy and achieving herd immunity.

Background: A healthcare system’s collapse due to a pandemic, such as the coronavirus disease 2019 (COVID-19), can expose healthcare workers (HCWs) to various mental health problems. This study aimed to investigate the impact of the COVID-19 pandemic on the depression and anxiety of HCWs. Methods: A nationwide questionnaire-based survey was conducted on HCWs who worked in healthcare facilities and public health centers in Korea in December 2020. Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure depression and anxiety. To investigate factors associated with depression and anxiety, stepwise multiple logistic regression analysis was performed. Results: A total of 1,425 participating HCWs were included. The mean depression score (PHQ-9) of HCWs before and after COVID-19 increased from 2.37 to 5.39, and the mean anxiety score (GAD-7) increased from 1.41 to 3.41. The proportion of HCWs with moderate to severe depression (PHQ-9 ≥ 10) increased from 3.8% before COVID-19 to 19.5% after COVID-19, whereas that of HCWs with moderate to severe anxiety (GAD-7 ≥ 10) increased from 2.0% to 10.1%. In our study, insomnia, chronic fatigue symptoms and physical symptoms after COVID-19, anxiety score (GAD-7) after COVID-19, living alone, and exhaustion were positively correlated with depression. Furthermore, post-traumatic stress symptoms, stress score (Global Assessment of Recent Stress), depression score (PHQ-9) after COVID-19, and exhaustion were positively correlated with anxiety. Conclusion In Korea, during the COVID-19 pandemic, HCWs commonly suffered from mental health problems, including depression and anxiety. Regularly checking the physical and mental health problems of HCWs during the COVID-19 pandemic is crucial, and social support and strategy are needed to reduce the heavy workload and psychological distress of HCWs.