Why school is crucial to increase vaccination coverage for children: Evaluation of school vaccination check program in South Korea 2021-2022.

The School Vaccination Check Program (SVCP) is a public health measure that aims to achieve high levels of National Immunization Program (NIP) vaccination coverage for children by checking the completion of the vaccination schedule for students when they enter elementary or middle school. Due to the COVID-19 pandemic, the SVCP was stopped in 2020 and 2021, and restarted in June-August 2022. In this study, we examined and quantified the relationship with SVCP and the vaccination uptake by comparing the vaccination coverage of 2021 and 2022. Based on the standard schedule, the vaccination records of DTaP5, IPV4, MMR2 and IJEV4 were evaluated for elementary school students. The Tdap6, IJEV5 and HPV1 were evaluated for the students from middle school. Using a difference-in-difference study design and national level big data, the study compared vaccination coverage as of August 2021 and 2022. The study found that the SVCP was effective in increasing vaccination coverage for targeted vaccinations such as DTaP5, IPV4, MMR2 and IJEV4 for elementary school students, and Tdap6, IJEV5 for middle school students. However, the SVCP did not show a statistically significant effect on increasing vaccination coverage on HPV1 for middle school students. School can play an important role to improve vaccination coverage. Therefore, close collaboration with health and education authority is crucial to accomplish successful vaccination program reducing vaccine preventable disease outbreaks in schools.

Evaluation of roadside air quality using deep learning models after the application of the diesel vehicle policy (Euro 6).

Euro 6 is the latest vehicle emission standards for pollutants such as CO, NO2 and PM, that all new vehicles must comply, and it was introduced in September 2015 in South Korea. This study examined the effect of Euro 6 by comparing the measured pollutant concentrations after 2016 (Euro 6-era) to the estimated concentrations without Euro 6. The concentration without Euro 6 was estimated by first modeling the air quality using various environmental factors related to diesel vehicles, meteorological conditions, temporal information such as date and precursors in 2002-2015 (pre-Euro 6-era), and then applying the model to predict the concentration after 2016. In this study, we used both recurrent neural network (RNN) and random forest (RF) algorithms to model the air quality and showed that RNN can achieve higher R2 (0.634 ~ 0.759 depending on pollutants) than RF, making it more suitable for air quality modeling. According to our results, the measured concentrations during 2016-2019 were lower than the concentrations predicted using RNN by - 1.2%, - 3.4%, and - 4.8% for CO, NO2 and PM10. Such reduction can be attributed to the result of Euro 6.

Changes in the Clinical Characteristics of Kawasaki Disease After Coronavirus Disease (COVID-19) Pandemic: A Database Analysis.

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) pandemic on Kawasaki disease (KD) has not yet been established. We investigated changes in the observed number and severity of KD cases and accompanying coronary artery complications during the COVID-19 pandemic in Korea. METHODS: This retrospective observational study included patients aged < 18 years with acute-phase KD diagnosed between March 2018 and February 2021. Data were extracted from the Clinical Data Warehouse that houses data from five affiliated university hospitals in Korea. We analyzed changes in the number of patient admissions and clinical characteristics, including cardiac complications, before and after the onset of the COVID-19 pandemic. RESULTS: A total of 475 admissions were included in the analysis. After March 2020, we observed a significant decrease of 33% in the number of hospitalizations for KD compared with the average number of hospitalizations during the previous 2 years. The number of admissions per month significantly decreased by 7.9 persons/month (95% confidence interval, -13.8 to -2.0; P < 0.05) compared with that before COVID-19. By contrast, the proportion of patients aged < 1 year with KD increased. The proportion of patients with refractory KD and the rate of cardiac complications did not change significantly. CONCLUSION: Since the onset of the COVID-19 pandemic, the total number of hospital admissions for KD has decreased in Korea. Although the proportion of admissions of infants aged < 1 year increased, no changes were observed in clinical courses and complications.

Impacts of COVID-19 on Air Quality through Traffic Reduction.

In 2020, the first case of COVID-19 was confirmed in Korea, and social distancing was implemented to prevent its spread. This reduced the movement of people, and changes in air quality were expected owing to reduced emissions. In the present paper, the impact of traffic volume change caused by COVID-19 on air quality in Seoul, Korea, is examined. Two regression analyses were performed using the generalized additive model (GAM), assuming a Gaussian distribution; the relationships between (1) the number of confirmed COVID-19 cases in 2020-2021 and the rate of change in the traffic volume in Seoul, and (2) the traffic volume and the rate of change in the air quality in Seoul from 2016 to 2019 were analyzed. The regression results show that traffic decreased by 0.00431% per COVID-19 case; when traffic fell by 1%, the PM10, PM2.5, CO, NO2, O3, and SO2 concentrations fell by 0.48%, 0.94%, 0.39%, 0.74%, 0.16%, and -0.01%, respectively. This mechanism accounts for air quality improvements in PM10, PM2.5, CO, NO2, and O3 in Seoul during 2020-2021. From these results, the majority of the reduction in pollutant concentrations in 2020-2021 appears to be the result of a long-term declining trend rather than COVID-19.

PEGylated nanoparticle albumin-bound steroidal ginsenoside derivatives ameliorate SARS-CoV-2-mediated hyper-inflammatory responses.

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on a global scale urges prompt and effective countermeasures. Recently, a study has reported that coronavirus disease-19 (COVID-19), the disease caused by SARS-CoV-2 infection, is associated with a decrease in albumin level, an increase in NETosis, blood coagulation, and cytokine level. Here, we present drug-loaded albumin nanoparticles as a therapeutic agent to resolve the clinical outcomes observed in severe SARS-CoV-2 patients. PEGylated nanoparticle albumin-bound (PNAB) was used to promote prolonged bioactivity of steroidal ginsenoside saponins, PNAB-Rg6 and PNAB-Rgx365. Our data indicate that the application of PNAB-steroidal ginsenoside can effectively reduce histone H4 and NETosis-related factors in the plasma, and alleviate SREBP2-mediated systemic inflammation in the PBMCs of SARS-CoV-2 ICU patients. The engineered blood vessel model confirmed that these drugs are effective in suppressing blood clot formation and vascular inflammation. Moreover, the animal model experiment showed that these drugs are effective in promoting the survival rate by alleviating tissue damage and cytokine storm. Altogether, our findings suggest that these PNAB-steroidal ginsenoside drugs have potential applications in the treatment of symptoms associated with severe SARS-CoV-2 patients, such as coagulation and cytokine storm.

Lung-selective 25-hydroxycholesterol nanotherapeutics as a suppressor of COVID-19-associated cytokine storm.

In response to the coronavirus disease-19 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), global efforts are focused on the development of new therapeutic interventions. For the treatment of COVID-19, selective lung-localizing strategies hold tremendous potential, as SARS-CoV-2 invades the lung via ACE2 receptors and causes severe pneumonia. Similarly, recent reports have shown the association of COVID-19 with decreased 25-hydroxycholesterol (25-HC) and increased cytokine levels. This mechanism, which involves the activation of inflammatory NF-κB- and SREBP2-mediated inflammasome signaling pathways, is believed to play a crucial role in COVID-19 pathogenesis, inducing acute respiratory distress syndrome (ARDS) and sepsis. To resolve those clinical conditions observed in severe SARS-CoV-2 patients, we report 25-HC and didodecyldimethylammonium bromide (DDAB) nanovesicles (25-HC@DDAB) as a COVID-19 drug candidate for the restoration of intracellular cholesterol level and suppression of cytokine storm. Our data demonstrate that 25-HC@DDAB can selectively accumulate the lung tissues and effectively downregulate NF-κB and SREBP2 signaling pathways in COVID-19 patient-derived PBMCs, reducing inflammatory cytokine levels. Altogether, our findings suggest that 25-HC@DDAB is a promising candidate for the treatment of symptoms associated with severe COVID-19 patients, such as decreased cholesterol level and cytokine storm.

Sustained Vaccination Coverage during the Coronavirus Disease 2019 Epidemic in the Republic of Korea.

Amid the COVID-19 pandemic, vaccination coverage may decline due to limited accessibility to healthcare. We assessed the impact of the COVID-19 pandemic on vaccination coverage and the incidence of vaccine-preventable diseases (VPDs) in the Republic of Korea. National vaccination coverage of 10 essential vaccines administered to children between January-June 2019 and January-June 2020 was analyzed. The national incidence of selected VPDs was compared for the corresponding periods. During the COVID-19 outbreak, the vaccination rate in children aged 0-35 months in Korea did not decrease significantly, whereas the vaccination rate for children aged 4-6 years decreased by 1.4-1.9%. The overall incidence of VPDs decreased by 10-50% between 2019 and 2020, especially with varicella. Thus, the COVID-19 pandemic did not result in a decrease in vaccination coverage among Korean children, which prevented a surge in VPD incidence. Maintaining essential vaccination coverage without interruption is important during the response to the COVID-19 pandemic.

Sustained Vaccination Coverage during the Coronavirus Disease 2019 Epidemic in the Republic of Korea

Amid the COVID-19 pandemic, vaccination coverage may decline due to limited accessibility to healthcare. We assessed the impact of the COVID-19 pandemic on vaccination coverage and the incidence of vaccine-preventable diseases (VPDs) in the Republic of Korea. National vaccination coverage of 10 essential vaccines administered to children between January–June 2019 and January–June 2020 was analyzed. The national incidence of selected VPDs was compared for the corresponding periods. During the COVID-19 outbreak, the vaccination rate in children aged 0–35 months in Korea did not decrease significantly, whereas the vaccination rate for children aged 4–6 years decreased by 1.4–1.9%. The overall incidence of VPDs decreased by 10–50% between 2019 and 2020, especially with varicella. Thus, the COVID-19 pandemic did not result in a decrease in vaccination coverage among Korean children, which prevented a surge in VPD incidence. Maintaining essential vaccination coverage without interruption is important during the response to the COVID-19 pandemic.

Long-acting nanoparticulate DNase-1 for effective suppression of SARS-CoV-2-mediated neutrophil activities and cytokine storm.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new strain of coronavirus not previously identified in humans. Globally, the number of confirmed cases and mortality rates of coronavirus disease 2019 (COVID-19) have risen dramatically. Currently, there are no FDA-approved antiviral drugs and there is an urgency to develop treatment strategies that can effectively suppress SARS-CoV-2-mediated cytokine storms, acute respiratory distress syndrome (ARDS), and sepsis. As symptoms progress in patients with SARS-CoV-2 sepsis, elevated amounts of cell-free DNA (cfDNA) are produced, which in turn induce multiple organ failure in these patients. Furthermore, plasma levels of DNase-1 are markedly reduced in SARS-CoV-2 sepsis patients. In this study, we generated recombinant DNase-1-coated polydopamine-poly(ethylene glycol) nanoparticulates (named long-acting DNase-1), and hypothesized that exogenous administration of long-acting DNase-1 may suppress SARS-CoV-2-mediated neutrophil activities and the cytokine storm. Our findings suggest that exogenously administered long-acting nanoparticulate DNase-1 can effectively reduce cfDNA levels and neutrophil activities and may be used as a potential therapeutic intervention for life-threatening SARS-CoV-2-mediated illnesses.