Impact of Infection Prevention Programs on Catheter-Associated Urinary Tract Infections Analyzed in Multicenter Study.

BACKGROUND: Catheter-associated urinary tract infections (CAUTIs) account for a large proportion of healthcare-associated infections and have a significant impact on morbidity, length of hospital stay, and mortality. Adherence to the recommended infection prevention practices can effectively reduce the incidence of CAUTIs. This study aimed to assess the characteristics of CAUTIs and the efficacy of prevention programs across hospitals of various sizes. METHODS: Intervention programs, including training, surveillance, and monitoring, were implemented. Data on the microorganisms responsible for CAUTIs, urinary catheter utilization ratio, rate of CAUTIs per 1,000 device days, and factors associated with the use of indwelling catheters were collected from 2017 to 2019. The incidence of CAUTIs and associated data were compared between university hospitals and small- and medium-sized hospitals. RESULTS: Thirty-two hospitals participated in the study, including 21 university hospitals and 11 small- and medium-sized hospitals. The microorganisms responsible for CAUTIs and their resistance rates did not differ between the two groups. In the first quarter of 2018, the incidence rate was 2.05 infections/1,000 device-days in university hospitals and 1.44 infections/1,000 device-days in small- and medium-sized hospitals. After implementing interventions, the rate gradually decreased in the first quarter of 2019, with 1.18 infections/1,000 device-days in university hospitals and 0.79 infections/1,000 device-days in small- and medium-sized hospitals. However, by the end of the study, the infection rate increased to 1.74 infections/1,000 device-days in university hospitals and 1.80 infections/1,000 device-days in small- and medium-sized hospitals. CONCLUSION: We implemented interventions to prevent CAUTIs and evaluated their outcomes. The incidence of these infections decreased in the initial phases of the intervention when adequate support and personnel were present. The rate of these infections may be reduced by implementing active interventions such as consistent monitoring and adherence to guidelines for preventing infections.

Interim Estimates of 2023-2024 Seasonal Influenza Vaccine Effectiveness Among Adults in Korea.

In the 2023-2024 season, the influenza epidemic in South Korea peaked earlier than in recent years. In this study, we aimed to estimate the interim vaccine effectiveness (VE) of the influenza vaccination to prevent influenza during the early season. From November 1, 2023, to December 31, 2023, we enrolled 2,632 subjects with influenza-like illness from eight hospitals participating in hospital-based influenza morbidity and mortality surveillance. A retrospective test-negative case-control study was conducted to estimate the VE. The results showed an adjusted VE of 22.5% (95% confidence interval [CI], 6.6 to 35.8) for the total population. The adjusted VE was 22.3% (95% CI, 6.1 to 35.7) for influenza A and 9.4% (95% CI, -51.3 to 45.7) for influenza A/H1N1. Full results of the analysis will be reported.

Updated Clinical Practice Guidelines for the Diagnosis and Management of Long COVID.

"Long COVID" is a term used to describe a condition when the symptoms and signs associated with coronavirus disease 2019 (COVID-19) persist for more than three months among patients infected with COVID-19; this condition has been reported globally and poses a serious public health issue. Long COVID can manifest in various forms, highlighting the need for appropriate evaluation and management by experts from various fields. However, due to the lack of clear clinical definitions, knowledge of pathophysiology, diagnostic methods, and treatment protocols, it is necessary to develop the best standard clinical guidelines based on the scientific evidence reported to date. We developed this clinical guideline for diagnosing and treating long COVID by analyzing the latest research data collected from the start of the COVID-19 pandemic until June 2023, along with the consensus of expert opinions. This guideline provides recommendations for diagnosis and treatment that can be applied in clinical practice, based on a total of 32 key questions related to patients with long COVID. The evaluation of patients with long COVID should be comprehensive, including medical history, physical examination, blood tests, imaging studies, and functional tests. To reduce the risk of developing long COVID, vaccination and antiviral treatment during the acute phase are recommended. This guideline will be revised when there is a reasonable need for updates based on the availability of new knowledge on the diagnosis and treatment of long COVID.

Psychopathology as long-term sequelae of maltreatment and socioeconomic disadvantage: Neurocognitive development perspectives.

Neuroscience research underscores the critical impact of adverse experiences on brain development. Yet, there is limited understanding of the specific pathways linking adverse experiences to accelerated or delayed brain development and their ultimate contributions to psychopathology. Here, we present new longitudinal data demonstrating that neurocognitive functioning during adolescence, as affected by adverse experiences, predicts psychopathology during young adulthood. The sample included 167 participants (52% male) assessed in adolescence and young adulthood. Adverse experiences were measured by early maltreatment experiences and low family socioeconomic status. Cognitive control was assessed by neural activation and behavioral performance during the Multi-Source Interference Task. Psychopathology was measured by self-reported internalizing and externalizing symptomatology. Results indicated that higher maltreatment predicted heightened frontoparietal activation during cognitive control, indicating delayed neurodevelopment, which, in turn predicted higher internalizing and externalizing symptomatology. Furthermore, higher maltreatment predicted a steeper decline in frontoparietal activation across adolescence, indicating neural plasticity in cognitive control-related brain development, which was associated with lower internalizing symptomatology. Our results elucidate the crucial role of neurocognitive development in the processes linking adverse experiences and psychopathology. Implications of the findings and directions for future research on the effects of adverse experiences on brain development are discussed.

Vaccination and the risk of post-acute sequelae after COVID-19 in the Omicron-predominant period.

OBJECTIVES: To assess the association of primary and third doses of vaccination with the risk of post-acute sequelae of COVID-19. METHODS: This retrospective cohort study utilized a combined database of nationwide health care claims data, COVID-19 patient registry, and vaccination records from South Korea. Individuals diagnosed with COVID-19 in the Omicron variant-dominant period of January-March 2022 were tracked for 30-120 days post-infection. The exposure of interest was the receipt of primary and third doses of the SARS-CoV-2 vaccine. The occurrence of 26 specific conditions in eight domains was compared using Cox regression with inverse probability of treatment weighting. RESULTS: This study included 394 773 unvaccinated individuals and 7 604 081 individuals receiving ≥2 doses of vaccine. Compared with unvaccinated individuals, vaccination with at least two doses was associated with a reduced risk (adjusted hazard ratio; 95% CI) of several conditions, including ischaemic heart disease (0.73; 0.57-0.94), heart failure (0.55; 0.48-0.63), cardiac dysrhythmia (0.72; 0.61-0.85), cardiac arrest (0.41; 0.33-0.51), pulmonary embolism (0.66; 0.52-0.84), venous thromboembolism (0.54; 0.44-0.66), acute renal failure (0.56; 0.46-0.67), new dialysis (0.45; 0.34-0.59), chronic obstructive pulmonary disease (0.74; 0.65-0.84), acute pancreatitis (0.64; 0.51-0.80), and diabetes (0.82; 0.71-0.95). The risks of heart failure, cardiac dysrhythmias, cardiac arrest, pulmonary embolism, and new dialysis were lower in those who were vaccinated with three doses compared with those who were vaccinated with two doses. DISCUSSION: Vaccination was associated with a decreased risk of post-acute sequelae of COVID-19, suggesting its potential role in mitigating the indirect impacts of COVID-19.

Trends of antimicrobial susceptibilities and multidrug-resistant colonization rate in patients transferred from long-term care facilities during 2017-2022: a cross-sectional study.

BACKGROUND: With the global increase in the older population, the proportion of those receiving care in long-term care facilities (LTCFs) has also been increasing. We assessed the epidemiology, antibiotic susceptibility, and colonization status of drug-resistant organisms in patients transferred from LTCFs. METHODS: We retrospectively reviewed the medical records of patients transferred from LTCFs between 2017 and 2022. The reasons for admission, antimicrobial susceptibility, and colonization rates of carbapenem-resistant Enterobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA), and carbapenem-resistant Acinetobacter baumannii (CRAB) were recorded. We analyzed the susceptibility and colonization rates by year to identify trends. RESULTS: Of the 936 patients transferred from LTCFs, 54.3% were admitted to the intensive care unit and 12.5% died. The most common reason for admission was infection (n = 573, 61.2%), followed by gastrointestinal bleeding (n = 67, 7.2%) and cerebrovascular disorder (n = 65, 6.9%). A total of 452 Enterobacterales strains were isolated, and their susceptibility rates to ciprofloxacin and cefotaxime were 33.3% and 35.6%, respectively. A total of 54.9% were extended-spectrum beta-lactamase-producing strains, and 4.9% of them were carbapenem-resistant, both of which showed an increasing trend (P = 0.024 and P < 0.001, respectively). The prevalence rates of CRE, CRAB, and MRSA colonization were 9.2%, 7.1%, and 23.1%, respectively. CRE colonization showed a significant increase (P < 0.001), with carbapenemase-producing Enterobacterales accounting for 75.9% of cases. CONCLUSIONS: Patients transferred from LTCFs are primarily affected by infections and exhibit high resistance rates. The increasing trend in CRE colonization rates each year highlights the need for the implementation of rigorous infection control measures for effective management.

Establishment of Safety Monitoring System for Vaccines Not Included in the National Immunization Program in Korea.

BACKGROUND: In Korea, there are no surveillance programs for vaccines that are not included in the national immunization program (NIP), and vaccine safety monitoring in the adult population is inadequate. This study aimed to establish a safety monitoring system for non-NIP vaccines in adults. METHODS: Frequently administered non-NIP vaccines were selected. Individuals were included if they received at least one of the selected vaccines at a participating institution and provided informed consent. Solicited and unsolicited adverse events were monitored using questionnaires sent through text messages on days 1, 3, 7, 28, and 90 post-vaccination. Selected adverse events of special interest (AESIs) were monitored monthly by retrospective review of electronic medical records. Causality was assessed according to the Korea Disease Control and Prevention Agency guidelines. RESULTS: Four vaccines (tetanus-diphtheria-pertussis [Tdap], pneumococcal conjugate 13-valent [PCV13], live zoster vaccine [ZVL], and recombinant zoster vaccine [RZV]) were selected, and their safety profiles were monitored at four tertiary hospitals and 10 primary care clinics. The response rates of the questionnaires on post-vaccination days 1, 7, 28, and 90 were 99.2%, 93.6%, 81.0%, and 48.7%, respectively. Of 555 AESI identified over 10 months, 10 cases received one of the selected non-NIP vaccines within 90 days of the event. CONCLUSION: We are establishing the first safety monitoring system for selected non-NIP vaccines in Korea since September 2022 and report its progress as of July 2023. However, continuous government support is essential for its maintenance and improvement.

Effectiveness of Bivalent mRNA Booster Vaccine Against COVID-19 in Korea.

BACKGROUND: Bivalent booster mRNA vaccines containing the omicron-variant strains have been introduced worldwide in the autumn of 2022. Nevertheless, the omicron subvariants evoked another large coronavirus disease 2019 (COVID-19) pandemic wave in late 2022 and early 2023. METHODS: A retrospective, test-negative, case-control study was conducted to estimate the vaccine effectiveness (VE) of bivalent COVID-19 vaccines in 8 university hospitals between January and February 2023. The case and control groups were divided based on nasopharyngeal COVID-19 real-time polymerase chain reaction results and matched based on age, sex, hospital, and date (week) of the test performed. The VE of the BA.1- or BA.4/BA.5-based mRNA vaccines were estimated. VE was calculated using the 1-adjusted odds ratio from multivariable logistic regression. RESULTS: In total, 949 patients and 947 controls were enrolled in this study. VE for the BA.4/BA.5-based bivalent mRNA vaccine was 43% (95% confidence interval [CI], 17, 61%). In subgroup analysis based on age and underlying medical conditions, BA.4/BA.5-based bivalent mRNA vaccine was effective against old adults aged ≥ 65-years (VE, 55%; 95% CI, 23, 73%) and individuals with comorbidities (VE, 54%; 95% CI, 23, 73%). In comparison, the BA.1-based bivalent mRNA vaccine did not demonstrate statistically significant effectiveness (VE, 25%; 95% CI, -8, 49%). CONCLUSION: The BA.4/BA.5-based bivalent mRNA booster vaccine provided significant protection against COVID-19 in the Korean adults, especially in the older adults aged ≥ 65 years and in individuals with underlying medical conditions.

Effectiveness of Antiviral Therapy on Long COVID: A Systematic Review and Meta-Analysis.

Antiviral treatment reduces the severity and mortality of SARS-CoV-2 infection; however, its effectiveness against long COVID-19 is unclear. This study aimed to evaluate the effectiveness of antiviral drugs in preventing long COVID and related hospitalizations/deaths. Scientific and medical databases were searched from 1 January 2020 to 30 June 2023. We included observational cohort studies comparing individuals receiving early antiviral therapy for COVID-19 and those receiving supportive treatment. A fixed-effects model was used to merge the effects reported in two or more studies. The risk of post-acute sequelae of COVID-19 (PASC) was combined as an odds ratio (OR). Six studies were selected, including a total of 3,352,235 participants. The occurrence of PASC was 27.5% lower in patients who received antiviral drugs during the early stages of SARS-CoV-2 infection (OR = 0.725; 95% confidence interval [CI] = 0.409-0.747) than in the supportive treatment group. Moreover, the risk of PASC-associated hospitalization and mortality was 29.7% lower in patients receiving early antiviral therapy than in the supportive treatment group (OR = 0.721; 95% CI = 0.697-0.794). Early antiviral therapy was associated with a reduced risk of PASC and related hospitalization or death. Thus, early antiviral therapy is recommended for at-risk individuals.

Community-Acquired Pneumococcal Pneumonia in Highly Vaccinated Population: Analysis by Serotypes, Vaccination Status, and Underlying Medical Conditions.

BACKGROUND: Targeted risk population has been highly vaccinated against pneumococcal diseases in South Korea. Despite this, the pneumococcal serotype distribution is evolving, which impedes efficient roll-out of vaccines. METHODS: This prospective cohort study included patients aged ≥ 19 years with community-acquired pneumonia (CAP) from five university hospitals in South Korea between September 2018 and July 2021. The outcomes of interest were the demographic and clinical characteristics of patients with CAP, pneumococcal serotype distribution, and risk factors of 30-day mortality in patients with pneumococcal CAP (pCAP). Considering the high seroprevalence, we analyzed the clinical characteristics of serotype 3 pCAP. RESULTS: A total of 5,009 patients hospitalized with CAP was included (mean age ± standard deviation, 70.3 ± 16.0 years; 3,159 [63.1%] men). Streptococcus pneumoniae was the leading causative agent of CAP (11.8% overall, 17.7% in individuals aged < 65 years with chronic medical conditions). Among the 280 serotyped Streptococcus pneumococcus, serotype 3 was the most common (10.0%), followed by serotypes 19A (8.9%), 34 (8.9%), and 35B (8.9%). Non-vaccine serotypes (serotype 35B [13.9%] and 34 [12.0%]) were the most prevalent in 108 individuals vaccinated with 23-valent pneumococcal polysaccharide vaccine (PPSV23). Serotype 3 was prevalent, irrespective of PPSV23 vaccination status, and more common in individuals with chronic lung disease (P = 0.008). Advanced age (adjusted odds ratio [aOR], 1.040; 95% confidence interval [CI], 1.011-1.071), long-term care facility residence (aOR, 2.161; 95% CI, 1.071-4.357), and bacteremia (aOR, 4.193; 95% CI, 1.604-10.962) were independent risk factors for 30-day mortality in patients with pCAP. PPSV23 vaccination reduced the risk of mortality (aOR, 0.507; 95% CI, 0.267-0.961). CONCLUSION: Serotype 3 and 19A were still the most common serotypes of pCAP in South Korea despite the national immunization program of 13-valent pneumococcal conjugated vaccine in children and PPSV23 in old adults. PPSV23 vaccination might reduce the risk of mortality in patients with pCAP.

Effectiveness and Adverse Events of Nirmatrelvir/Ritonavir Versus Molnupiravir for COVID-19 in Outpatient Setting: Multicenter Prospective Observational Study.

BACKGROUND: In this study, we aimed to compare the effectiveness and adverse reactions of nirmatrelvir/ritonavir and molnupiravir in high-risk outpatients with coronavirus disease 2019 (COVID-19). METHODS: This multicenter prospective observational study evaluated the rate of hospitalization, death, and adverse events within 28 days of oral antiviral agent prescription (molnupiravir, n = 240; nirmatrelvir/ritonavir, n = 240) to 480 nonhospitalized adult patients with COVID-19 from August 2, 2022 to March 31, 2023. RESULTS: Patients receiving molnupiravir had a higher prevalence of comorbidities (85.8% vs. 70.4%; P < 0.001) and a higher Charlson comorbidity index (2.8 ± 1.4 vs. 2.5 ± 1.5; P = 0.009) than those receiving nirmatrelvir/ritonavir. Three patients required hospitalization (nirmatrelvir/ritonavir group, n = 1 [0.4%]; molnupiravir group, n = 2 [0.8%]; P = 1.000). Nirmatrelvir/ritonavir was associated with a higher risk of adverse events than molnupiravir (odds ratio [OR], 1.96; 95% confidence interval [CI], 1.27-3.03), especially for patients aged 65 years and older (OR, 3.04; 95% CI, 1.71-5.39). The severity of adverse events in both groups was mild to moderate and improved after discontinuation of medication. In the molnupiravir group, age ≥ 65 years (OR, 0.43 95% CI, 0.22-0.86) and appropriate vaccination (OR, 0.37; 95% CI, 0.15-0.91) reduced the occurrence of adverse events. CONCLUSION: The rates of hospitalization and death were low and not significantly different between high-risk patients who received either nirmatrelvir/ritonavir or molnupiravir. Although adverse events were more frequent with nirmatrelvir/ritonavir than with molnupiravir, none were severe. Nirmatrelvir/ritonavir can be safely used to treat COVID-19, while molnupiravir could be considered as an alternative treatment option for high-risk groups.

KAT6A mutations in Arboleda-Tham syndrome drive epigenetic regulation of posterior HOXC cluster.

Arboleda-Tham Syndrome (ARTHS) is a rare genetic disorder caused by heterozygous, de novo mutations in Lysine(K) acetyltransferase 6A (KAT6A). ARTHS is clinically heterogeneous and characterized by several common features, including intellectual disability, developmental and speech delay, and hypotonia, and affects multiple organ systems. KAT6A is the enzymatic core of a histone-acetylation protein complex; however, the direct histone targets and gene regulatory effects remain unknown. In this study, we use ARTHS patient (n = 8) and control (n = 14) dermal fibroblasts and perform comprehensive profiling of the epigenome and transcriptome caused by KAT6A mutations. We identified differential chromatin accessibility within the promoter or gene body of 23% (14/60) of genes that were differentially expressed between ARTHS and controls. Within fibroblasts, we show a distinct set of genes from the posterior HOXC gene cluster (HOXC10, HOXC11, HOXC-AS3, HOXC-AS2, and HOTAIR) that are overexpressed in ARTHS and are transcription factors critical for early development body segment patterning. The genomic loci harboring HOXC genes are epigenetically regulated with increased chromatin accessibility, high levels of H3K23ac, and increased gene-body DNA methylation compared to controls, all of which are consistent with transcriptomic overexpression. Finally, we used unbiased proteomic mass spectrometry and identified two new histone post-translational modifications (PTMs) that are disrupted in ARTHS: H2A and H3K56 acetylation. Our multi-omics assays have identified novel histone and gene regulatory roles of KAT6A in a large group of ARTHS patients harboring diverse pathogenic mutations. This work provides insight into the role of KAT6A on the epigenomic regulation in somatic cell types.

Immunogenicity and safety of SARS-CoV-2 recombinant protein nanoparticle vaccine GBP510 adjuvanted with AS03: interim results of a randomised, active-controlled, observer-blinded, phase 3 trial.

Background: GBP510 vaccine contains self-assembling, recombinant nanoparticles displaying SARS-CoV-2 spike receptor-binding domains. We report interim phase 3 immunogenicity results for GBP510 adjuvanted with AS03 (GBP510/AS03) compared with ChAdOx1-S (Vaxzevria, AstraZeneca) in healthy adults aged ≥18 years, up to 6 months after the second dose. Methods: This was a randomised, active-controlled, observer-blinded, parallel group, phase 3 study, conducted at 38 sites across six countries (South Korea, Philippines, Thailand, Vietnam, Ukraine and New Zealand). Cohort 1 (no history of SARS-CoV-2 infection/COVID-19 vaccination) was randomised 2:1 to receive two doses of GBP510/AS03 or ChAdOx1-S (immunogenicity and safety), while Cohort 2 (regardless of baseline serostatus) was randomised 5:1 (safety). Primary objectives were to demonstrate superiority in geometric mean titre (GMT) and non-inferiority in seroconversion rate (SCR; ≥4-fold rise from baseline) of GBP510/AS03 vs. ChAdOx1-S for neutralising antibodies against the ancestral strain by live-virus neutralisation assay. Secondary objectives included assessment of safety and reactogenicity (long-term 6 months cut-off date: 09 August 2022). This study was registered on ClinicalTrials.gov (NCT05007951). Findings: Between 30 August 2021 and 11 January 2022, a total of 4913 participants were screened and 4036 participants (1956 in Cohort 1 and 2080 in Cohort 2) who met eligibility criteria were enrolled and randomised to receive 2 doses of GBP510/AS03 (n = 3039) or ChAdOx1-S (n = 997). Most participants were Southeast Asian (81.5%) and aged 18-64 years (94.7%). The primary objectives assessed in per-protocol set included 877 participants in GBP510/AS03 and 441 in ChAdOx1-S group: at 2 weeks after the second vaccination, the GMT ratio (GBP510/AS03/ChAdOx1-S) in per-protocol set was 2.93 (95% CI 2.63-3.27), demonstrating superiority (95% CI lower limit >1) of GBP510/AS03; the between-group SCR difference of 10.8% (95% CI 7.68-14.32) also satisfied the non-inferiority criterion (95% CI lower limit > -5%). Neutralizing antibody titres sustained higher for the GBP510/AS03 group compared to the ChAdOx1-S group through 6 months after the second vaccination. In Safety analysis (Cohort 1 & 2), the proportion of participants with adverse events (AEs) after any vaccination was higher with GBP510/AS03 vs. ChAdOx1-S for solicited local AEs (56.7% vs. 49.2%), but was similar for solicited systemic AEs (51.2% vs. 53.5%) and unsolicited AEs (13.3% vs. 14.6%) up to 28 days after the second vaccination. No safety concerns were identified during follow-up for 6 months after the second vaccination. Interpretation: Our interim findings suggested that GBP510/AS03 met the superiority criterion for neutralising antibodies and non-inferiority criterion for SCR compared with ChAdOx1-S, and showed a clinically acceptable safety profile. Funding: This work was supported, in whole or in part, by funding from CEPI and the Bill & Melinda Gates Foundation Investments INV-010680 and INV-006462. The Bill & Melinda Gates Foundation supported this project for the generation of IND-enabling data and CEPI supported this clinical study.

KAT6A mutations in Arboleda-Tham syndrome drive epigenetic regulation of posterior HOXC cluster.

Arboleda-Tham Syndrome (ARTHS) is a rare genetic disorder caused by heterozygous, de novo truncating mutations in Lysine(K) acetyltransferase 6A (KAT6A). ARTHS is clinically heterogeneous and characterized by several common features including intellectual disability, developmental and speech delay, hypotonia and affects multiple organ systems. KAT6A is highly expressed in early development and plays a key role in cell-type specific differentiation. KAT6A is the enzymatic core of a histone-acetylation protein complex, however the direct histone targets and gene regulatory effects remain unknown. In this study, we use ARTHS patient (n=8) and control (n=14) dermal fibroblasts and perform comprehensive profiling of the epigenome and transcriptome caused by KAT6A mutations. We identified differential chromatin accessibility within the promoter or gene body of 23%(14/60) of genes that were differentially expressed between ARTHS and controls. Within fibroblasts, we show a distinct set of genes from the posterior HOXC gene cluster (HOXC10, HOXC11, HOXC-AS3, HOXC-AS2, HOTAIR) that are overexpressed in ARTHS and are transcription factors critical for early development body segment patterning. The genomic loci harboring HOXC genes are epigenetically regulated with increased chromatin accessibility, high levels of H3K23ac, and increased gene-body DNA methylation compared to controls, all of which are consistent with transcriptomic overexpression. Finally, we used unbiased proteomic mass spectrometry and identified two new histone post-translational modifications (PTMs) that are disrupted in ARTHS: H2A and H3K56 acetylation. Our multi-omics assays have identified novel histone and gene regulatory roles of KAT6A in a large group of ARTHS patients harboring diverse pathogenic mutations. This work provides insight into the role of KAT6A on the epigenomic regulation in somatic cell types.

Risk estimation of lifted mask mandates and emerging variants using mathematical model.

Background: More than half of the population in Korea had a prior COVID-19 infection. In 2022, most nonpharmaceutical interventions, except mask-wearing indoors, had been lifted. And in 2023, the indoor mask mandates were eased. Methods: We developed an age-structured compartmental model that distinguishes vaccination history, prior infection, and medical staff from the rest of the population. Contact patterns among hosts were separated based on age and location. We simulated scenarios with the lifting of the mask mandate all at once or sequentially according to the locations. Furthermore, we investigated the impact of a new variant assuming that it has higher transmissibility and risk of breakthrough infection. Results: We found that the peak size of administered severe patients may not exceed 1100 when the mask mandate is lifted everywhere, and 800 if the mask mandate only remains in the hospital. If the mask mandate is lifted in a sequence (except hospital), then the peak size of administered severe patients may not exceed 650. Moreover, if the new variant has both higher transmissibility and immune reduction, the effective reproductive number of the new variant is approximately 3 times higher than that of the current variant, and additional interventions may be needed to keep the administered severe patients from exceeding 2,000, which is the critical level we set. Conclusion: Our findings showed that the lifting of the mask mandate, except in hospitals, would be more manageable if implemented sequentially. Considering a new variant, we found that depending on the population immunity and transmissibility of the variant, wearing masks and other interventions may be necessary for controlling the disease.

Modelling the effects of social distancing, antiviral therapy, and booster shots on mitigating Omicron spread.

As the COVID-19 situation changes because of emerging variants and updated vaccines, an elaborate mathematical model is essential in crafting proactive and effective control strategies. We propose a COVID-19 mathematical model considering variants, booster shots, waning, and antiviral drugs. We quantify the effects of social distancing in the Republic of Korea by estimating the reduction in transmission induced by government policies from February 26, 2021 to February 3, 2022. Simulations show that the next epidemic peak can be estimated by investigating the effects of waning immunity. This research emphasizes that booster vaccination should be administered right before the next epidemic wave, which follows the increasing waned population. Policymakers are recommended to monitor the waning population immunity using mathematical models or other predictive methods. Moreover, our simulations considering a new variant's transmissibility, severity, and vaccine evasion suggest intervention measures that can reduce the severity of COVID-19.

Estimation of monkeypox spread in a nonendemic country considering contact tracing and self-reporting: A stochastic modeling study.

In May 2022, monkeypox started to spread in nonendemic countries. To investigate contact tracing and self-reporting of the primary case in the local community, a stochastic model is developed. An algorithm based on Gillespie's stochastic chemical kinetics is used to quantify the number of infections, contacts, and duration from the arrival of the primary case to the detection of the index case (or until there are no more local infections). Different scenarios were set considering the delay in contact tracing and behavior of infectors. We found that the self-reporting behavior of a primary case is the most significant factor affecting outbreak size and duration. Scenarios with a self-reporting primary case have an 86% reduction in infections (average: 5-7, in a population of 10 000) and contacts (average: 27-72) compared with scenarios with a non-self-reporting primary case (average number of infections and contacts: 27-72 and 197-537, respectively). Doubling the number of close contacts per day is less impactful compared with the self-reporting behavior of the primary case as it could only increase the number of infections by 45%. Our study emphasizes the importance of the prompt detection of the primary case.

Differential Associations of Adversity Profiles with Adolescent Cognitive Control and Psychopathology.

Adverse childhood experiences are common and have long-term consequences for biological and psychosocial adjustment. We used a person-centered approach to characterize distinct profiles of adversity in early adolescence and examined associations with later cognitive control and psychopathology. The sample included 167 adolescents (47% female) and their primary caregivers who participated in a longitudinal study across four time points (approximately one year between assessments). At Time 1 (Mage = 14 years), we measured seven indicators of adversity: socioeconomic disadvantage, abuse, neglect, household chaos, parent substance use, parent depression, and negative life events. At Times 2-4, adolescents' behavioral performance and functional activation during a cognitive control task were measured. At Time 5, adolescents and their caregiver reported on adolescent internalizing and externalizing symptomatology. Using latent profile analysis, we identified four distinct adversity subgroups: a low exposure group, a neglect group, a household instability group, and a poly-adversity group. These groups significantly differed on subsequent levels of psychopathology, but not cognitive control. Specifically, the poly-adversity group reported significantly higher levels of both internalizing and externalizing symptomatology relative to the low exposure group, and the household instability group demonstrated elevated risk for externalizing symptomatology. When using a cumulative risk approach, higher levels of adversity exposure were associated with significantly worse cognitive control performance (but not neural activation). These results suggest that psychopathology outcomes may be differentially predicted by distinct patterns of risk, and that cognitive control impairment may be more strongly predicted by cumulative risk.

Correlation Between Third Dose of COVID-19 Vaccines and Regional Case Fatality Rates During the Omicron Wave in Korea.

This study seeks to find the correlation between case fatality rates (CFRs) and third-dose vaccination coverage in 244 counties (si/gun/gu) of South Korea during the omicron variant wave. Multivariate regression analyses report that the higher third-dose vaccination rates were correlated with lower regional CFRs, when controlling for age structure. If the third-dose vaccination rate of a county is higher by 10%, it would have a CFR lower by 0.05% (95% confidence interval, 0.03-0.08%). As the number of cumulative confirmed cases in South Korea was 16,353,495 as of April 20, 2022, a lower CFR by 0.03-0.08% is equivalent to 4,394-12,448 lives (8.6-24.4 per 100,000) spared. County-specific characteristics, such as age structure, intensive care unit availability, and the level of non-pharmaceutical interventions may also affect the extent of this correlation. The conclusion implicates the potential role of coronavirus disease 2019 vaccines in reducing the pressure on the regional healthcare capacity.

Delivery of stable ultra-thin liquid sheets in vacuum for biochemical spectroscopy.

The development of ultra-thin flat liquid sheets capable of running in vacuum has provided an exciting new target for X-ray absorption spectroscopy in the liquid and solution phases. Several methods have become available for delivering in-vacuum sheet jets using different nozzle designs. We compare the sheets produced by two different types of nozzle; a commercially available borosillicate glass chip using microfluidic channels to deliver colliding jets, and an in-house fabricated fan spray nozzle which compresses the liquid on an axis out of a slit to achieve collision conditions. We find in our tests that both nozzles are suitable for use in X-ray absorption spectroscopy with the fan spray nozzle producing thicker but more stable jets than the commercial nozzle. We also provide practical details of how to run these nozzles in vacuum.