Estimating the number of severe COVID-19 cases and COVID-19-related deaths averted by a nationwide vaccination campaign in Republic of Korea

Objectives@#The Korea Disease Control and Prevention Agency promotes vaccination by regularly providing information on its benefits for reducing the severity of coronavirus disease 2019 (COVID-19). This study aimed to analyze the number of averted severe COVID-19 cases and COVID-19-related deaths by age group and quantify the impact of Republic of Korea’s nationwide vaccination campaign. @*Methods@#We analyzed an integrated database from the beginning of the vaccination campaign on February 26, 2021 to October 15, 2022. We estimated the cumulative number of severe cases and COVID-19-related deaths over time by comparing observed and estimated cases among unvaccinated and vaccinated groups using statistical modeling. We compared daily age-adjusted rates of severe cases and deaths in the unvaccinated group to those in the vaccinated group and calculated the susceptible population and proportion of vaccinated people by age. @*Results@#There were 23,793 severe cases and 25,441 deaths related to COVID-19. We estimated that 119,579 (95% confidence interval [CI], 118,901–120,257) severe COVID-19 cases and 137,636 (95% CI, 136,909–138,363) COVID-19-related deaths would have occurred if vaccination had not been performed. Therefore, 95,786 (95% CI, 94,659–96,913) severe cases and 112,195 (95% CI, 110,870–113,520) deaths were prevented as a result of the vaccination campaign. @*Conclusion@#We found that, if the nationwide COVID-19 vaccination campaign had not been implemented, the number of severe cases and deaths would have been at least 4 times higher. These findings suggest that Republic of Korea’s nationwide vaccination campaign reduced the number of severe cases and COVID-19 deaths.

Comparative Effectiveness of COVID-19 Bivalent Versus Monovalent mRNA Vaccines in the Early Stage of Bivalent Vaccination in Korea: October 2022 to January 2023

Background@#This retrospective observational matched-cohort study of 2,151,216 individuals from the Korean coronavirus disease 2019 (COVID-19) vaccine effectiveness cohort aimed to evaluate the comparative effectiveness of the COVID-19 bivalent versus monovalent vaccines in providing additional protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, critical infection, and death in Korea. @*Methods@#Among individuals, those vaccinated with COVID-19 bivalent vaccines were matched in a 1:1 ratio with those who were vaccinated with monovalent vaccines (bivalent vaccines non-recipients) during the observation period. We fitted a time-dependent Cox proportional-hazards model to estimate hazard ratios (HRs) of COVID-19 outcomes for infection, critical infection, and death, and we defined vaccine effectiveness (VE) as 1–HR. @*Results@#Compared with the bivalent vaccination group, the incidence proportions in the monovalent vaccination group were approximately three times higher for infection, nine times higher for critical infection, and 11 times higher for death. In the early stage of bivalent vaccination, relative VE of bivalent vaccine against monovalent vaccine was 42.4% against SARS-CoV-2 infection, 81.3% against critical infection, and 85.3% against death. In addition, VE against critical infection and death according to the elapsed period after bivalent vaccination was maintained at > 70%. @*Conclusion@#The bivalent booster dose provided additional protection against SARS-CoV-2 infections, critical infections, and deaths during the omicron variant phase of the COVID-19 pandemic.

Risk Factors Related to COVID-19Reinfection and Fatality During the Omicron (BA.1/BA.2) Period in Korea

Background@#This study aimed to investigate the deaths due to coronavirus disease 2019 (COVID-19) reinfection and related risk factors. @*Methods@#National cohort data were collected for a six-month period when omicron BA.1/BA.2 variant was dominant in South Korea. @*Results@#The long-term care facility residents (adjusted odds ratio, 3.11; 95% confidence interval [CI], 2.98–3.25) had significantly higher risk of reinfection than the general population. The risk of reinfection was significantly lower for persons with 2 or more vaccine doses compared to the unvaccinated. The risk of death was significantly higher in the reinfection group than in the primary infection group for persons in the 60–74 years age group (adjusted relative risk [aRR], 1.62; 95% CI, 1.19–2.20), and immunocompromised group (aRR, 4.56; 95% CI, 2.34–8.90). @*Conclusion@#In these data, vaccination history was significantly related to reduced COVID-19 reinfection and severe progression, and scheduled vaccinations were important even with a history of infection.

Vaccine Effectiveness Against Severe Disease and Death for Patients With COVID-19 During the Delta-Dominant and Omicron-Emerging Periods:A K-COVE Study

National cohort data collected during the coronavirus disease 2019 (COVID-19) delta and omicron periods in Korea revealed a lower risk of severe infection in recipients of three doses of the COVID-19 vaccine (adjusted odds ratio [aOR], 0.05–0.08). The risk of death was reduced during the omicron period compared to the delta period (aOR, 0.75; 95% confidence interval, 0.67–0.84).

Effectiveness of Heterologous COVID-19 Vaccine Booster in Korean Elderly Population, 2022

We conducted a cohort study to assess vaccine effectiveness (VE) of coronavirus disease 2019 vaccine combinations on severe acute respirator y syndrome coronavirus 2 critical infection and death among elderly population in Korea. From Januar y to August 2022, VE against death for 4 doses mRNA recipients was 96.1%, whereas 1-dose viral vector + 3-dose mRNA recipients had VE of 90.8%.

Importation and Transmission of SARS-CoV-2 B.1.1.529 (Omicron) Variant of Concern in Korea, November 2021

In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel.There may be more transmissions with this VOC in Korea than reported.

Ovarian Gynandroblastoma with a Juvenile Granulosa Cell Tumor Component in a Postmenopausal Woman: A Case Report and Literature Review

Gynandroblastoma is an extremely rare sex cord-stromal tumor with both female (granulosa cell tumor) and male (Sertoli-Leydig cell tumor) elements. Juvenile granulosa cell tumors are also very rare and are so named because they usually occur in children and adolescents. A 71-year-old woman with right upper quadrant abdominal pain visited our hospital. Pelvic computed tomography showed a large multilocular cystic mass, suspected to be of ovarian origin. We performed a total abdominal hysterectomy (total abdominal hysterectomy was performed) with bilateral salpingo-oophorectomy. A 13-cm multilocular cystic mass with serous fluid was observed in her right ovary. Upon microscopic examination, the solid component of the mass showed both Sertoli-Leydig cell and juvenile granulosa cell differentiation, which we diagnosed as gynandroblastoma. Gynandroblastoma with a juvenile granulosa cell tumor component is extremely rare and, until now, only six cases have been reported in the English literature. We report the first gynandroblastoma with a juvenile granulosa cell tumor component diagnosed in an elderly patient, along with a literature review.

The Cut-off Values of Surrogate Measures for Insulin Sensitivity in a Healthy Population in Korea according to the Korean National Health and Nutrition Examination Survey (KNHANES) 2007–2010

BACKGROUND: This study aimed to identify the gender-specific characteristics of the surrogate measures of insulin resistance and to establish valid cut-off values for metabolic abnormalities in a representative sample in Korea. METHODS: Data were collected from the datasets of the Korean National Health and Nutrition Examination Survey between 2007 and 2010. The total number of eligible participants was 10,997. We used three measures of insulin resistance: the homeostasis model assessment-insulin resistance (HOMA-IR), McAuley index, and triglyceride and glucose (TyG) index. The estimated cut-off values were determined using the highest score of the Youden index. RESULTS: The area under the curve (AUC) of the HOMA-IR, McAuley index, and TyG index were 0.737 (95% confidence interval [CI], 0.725–0.750), 0.861 (95% CI, 0.853–0.870), and 0.877 (95% CI, 0.868–0.885), respectively. The cut-off values of the HOMA-IR were 2.20 in men, 2.55 in premenopausal women, and 2.03 in postmenopausal women, and those of the McAuley index were 6.4 in men and 6.6 in premenopausal and postmenopausal women. For the TyG index, the cut-off values were 4.76 in men and 4.71 in premenopausal and postmenopausal women. CONCLUSION: In conclusion, the present study provides the valid cut-off values of the indirect surrogate measures of insulin sensitivity. These values may be used as reference for insulin sensitivity in a clinical setting and may provide a simple and supplementary method for identifying populations at risk of insulin resistance.

BCR-ABL₁ transcripts (MR(4.5)) at post-transplant 3 months as an early predictor for long-term outcomes in chronic myeloid leukemia

BACKGROUND/AIMS: The aim of this study was to identify the role of BCR-ABL1 transcript level as a predictor for post-transplant relapse and outcome in patients who underwent allogeneic stem cell transplantation (SCT) for chronic phase (CP) chronic myeloid leukemia (CML). METHODS: Of 101 patients receiving allograft in CML CP, 85 had available quantitative reverse transcriptase polymerase chain reaction data at post-transplant 3 months. These patients were divided into two groups according to molecular response (MR(4.5)), defined as a BCR-ABL₁ transcript level ≤ 0.0032% on the international scale, at 3 months based on receiver operating characteristic curve analysis of relapse. RESULTS: The 4-year overall survival and event-free survival (EFS) were 80.6% and 57.3%, respectively, and the cumulative incidence of relapse at 4 years was 29.6% after a median follow-up of 126.4 months. We performed multivariate analyses including potential variables to evaluate the early predictive role of MR(4.5) at 3 months and found that MR(4.5) at 3 months was associated with a higher EFS (p = 0.028) and showed a trend for a lower relapse rate (p = 0.089). CONCLUSIONS: our results imply that frequent molecular monitoring and immune suppressive therapy modulation are required for patients without reduction of BCR-ABL1 transcripts to this level after SCT.

Neural Ablation and Regeneration in Pain Practice

A nerve block is an effective tool for diagnostic and therapeutic methods. If a diagnostic nerve block is successful for pain relief and the subsequent therapeutic nerve block is effective for only a limited duration, the next step that should be considered is a nerve ablation or modulation. The nerve ablation causes iatrogenic neural degeneration aiming only for sensory or sympathetic denervation without motor deficits. Nerve ablation produces the interruption of axonal continuity, degeneration of nerve fibers distal to the lesion (Wallerian degeneration), and the eventual death of axotomized neurons. The nerve ablation methods currently available for resection/removal of innervation are performed by either chemical or thermal ablation. Meanwhile, the nerve modulation method for interruption of innervation is performed using an electromagnetic field of pulsed radiofrequency. According to Sunderland's classification, it is first and foremost suggested that current neural ablations produce third degree peripheral nerve injury (PNI) to the myelin, axon, and endoneurium without any disruption of the fascicular arrangement, perineurium, and epineurium. The merit of Sunderland's third degree PNI is to produce a reversible injury. However, its shortcoming is the recurrence of pain and the necessity of repeated ablative procedures. The molecular mechanisms related to axonal regeneration after injury include cross-talk between axons and glial cells, neurotrophic factors, extracellular matrix molecules, and their receptors. It is essential to establish a safe, long-standing denervation method without any complications in future practices based on the mechanisms of nerve degeneration as well as following regeneration.

Laboratory-acquired dengue virus infection by needlestick injury: a case report, South Korea, 2014

BACKGROUND: Dengue fever is one of the most dominant vector-borne diseases, putting approximately 3.9 billion people at risk worldwide. While it is generally vector-borne, other routes of transmission such as needlestick injury are possible. Laboratory workers can be exposed to dengue virus transcutaneously by needlestick injury. This is the first case, to our knowledge, of dengue virus infection by needlestick injury in a laboratory environment. This paper evaluates the risk and related health concerns of laboratory workers exposed to dengue virus. CASE PRESENTATION: We evaluated a 30-year-old female laboratory worker exposed to the dengue virus by needlestick injury while conducting virus filtering. During admission, she showed symptoms of fever, nausea, myalgia, and a characteristic maculopapular rash with elevated aspartate aminotransferase (AST) of 235 IU/L and alanine aminotransferase (ALT) of 269 IU/L. She had been diagnosed by a positive nonstructural protein 1 (NS1) antigen (Ag) rapid test one day prior to symptom onset along with positive immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) on the ninth day of symptom onset. Reverse transcription polymerase chain reaction (RT-PCR), also conducted on the ninth day, was negative. After proper symptomatic treatment, she recovered without any sequelae. As a result of thorough epidemiologic investigation, it was determined that she had tried to recap the needle during the virus filtering procedure and a subsequent needlestick injury occurred. CONCLUSIONS: In the context of health promotion of laboratory workers, we suggest that the laboratory biosafety manual be revised and reinforced, and related prevention measures be implemented. Furthermore, health authorities and health care providers in Korea should be fully informed of proper dengue fever management.

Reversible Pulmonary Arterial Hypertension Associated with Dasatinib for Chronic Myeloid Leukemia / Journal of the Korean Cancer Association, 대한암학회지

We describe two cases of pulmonary arterial hypertension (PAH) that occurred under dasatinib treatment and were resolved after dasatinib discontinuation. Two patients with chronic phase chronic myeloid leukemia (CML) were switched to dasatinib therapy because of hematological progress while receiving imatinib. These patients had New York Heart Association (NYHA) functional class II dyspnea with elevated right ventricular systolic pressure (RVSP), which progressed under dasatinib treatment. After dasatinib treatment was discontinued, subjective symptoms were improved to NYHA functional class I and the follow-up transthoracic Doppler echocardiography showed improved RVSP. Treatment with an alternate tyrosine kinase inhibitor was initiated and had been continued without development of dyspnea or elevation of RVSP. This report suggests that dasatinib can cause the reversible PAH, therefore, routine cardiopulmonary evaluation before and during treatment with dasatinib may be needed in CML patients with clinical manifestations.

Enhancement of Allergen-induced Airway Inflammation by NOX2 Deficiency

BACKGROUND: NADPH oxidase (NOX) modulates cell proliferation, differentiation and immune response through generation of reactive oxygen species. Particularly, NOX2 is recently reported to be important for regulating Treg cell differentiation of CD4+ T cells. METHODS: We employed ovalbumin-induced airway inflammation in wild-type and NOX2-deficient mice and analyzed tissue histopathology and cytokine profiles. RESULTS: We investigated whether NOX2-deficiency affects T cell-mediated airway inflammation. Ovalbumin injection which activates T cell-mediated allergic response increased airway inflammation in wild-type mice, as evidenced by increased immune cell infiltration, allergic cytokine expression, and goblet cell hyperplasia in the lung. Interestingly, NOX2 knockout (KO) mice were more susceptible to allergen-induced lung inflammation compared to wild-type mice. Immune cells including neutrophils, lymphocytes, macrophages, and eosinophils were drastically infiltrated into the lung of NOX2 KO mice and mucus secretion was substantially increased in deficiency of NOX2. Furthermore, inflammatory allergic cytokines and eotaxin were significantly elevated in NOX2 KO mice, in accordance with enhanced generation of inflammatory cytokines interleukin-17 and interferon-gamma by CD4+ T cells. CONCLUSION: These results indicate that NOX2 deficiency favorably produces inflammatory cytokines by T cells and thus increases the susceptibility to severe airway inflammation.

Anti-TNFalpha Treatment for Two Cases of Acute Generalized Exanthematous Pustulosis Caused by Rhus Hypersensitivity / 대한내과학회지

Acute generalized exanthematous pustulosis (AGEP) is characterized by the rapid occurrence of many sterile, nonfollicular pustules on an edematous erythema accompanied by leucocytosis and fever. It is usually attributed to drugs, including herbal medications such as rhus in Korea. We report two cases of AGEP due to rhus hypersensitivity treated with anti-tumor necrosis factor (TNF)-alpha. The patients developed a generalized erythematous rash and edema, particularly on the face, with high fever and leukocytosis several days after ingesting rhus chicken or contacting rhus extract. Following treatment with a systemic steroid, the skin rash spread to the entire body and pustules arose on an edematous erythema. After stopping the systemic steroid and administering a subcutaneous injection of Etanercept, the pustular rashes, fever, and edema improved within 4 days. These results suggest that anti-TNF-alpha treatment may be effective for rapidly improving AGEP.

A Case of Small Bowel Obstruction Due to a Paracecal Hernia

Internal hernias are rare causes of small bowel obstruction, and one such internal hernia is the paracecal hernia. We report a case of a small bowel obstruction related to a paracecal hernia in which a preoperative diagnosis was made on computed tomography. A laparotomy was performed for definitive diagnosis and treatment. The surgery achieved a good outcome.

Acute Urticaria Induced by Oral Methylprednisolone

Although corticosteroids have immunosuppressive, anti-inflammatory, and anti-allergic effects, allergic reactions are rare. We report a case involving a 52-year-old-female with acute urticaria caused by oral methylprednisolone. The patient had experienced aspirin-exacerbated respiratory disease (AERD) for 13 years with frequent asthma exacerbations. Symptoms of asthma exacerbations improved with short-term treatments of systemic steroids, including methylprednisolone or deflazacort, which had been well tolerated. However, the current admission was prompted by the development of acute generalized urticaria following the oral ingestion of methylprednisolone (8 mg) for relief of symptoms. An oral provocation test with 4 mg oral methylprednisolone led to generalized urticaria 20 minutes later, confirming the causal association. This is the first report of acute urticaria caused by oral methylprednisolone in a patient with AERD.

Value and Interpretation of Resection Margin after a Colonoscopic Polypectomy for Malignant Polyps

PURPOSE: This study was designed to compare the clinicopathologic findings of an endoscopic polypectomy for malignant polyps with subsequent surgery and to evaluate the appropriateness of the pathologic finding criterion of the resection margin as an indicator for surgery in cases of malignant colorectal polyps. METHODS: We examined the clinicopathologic characteristics, complications and prognoses among the patients who underwent a colonoscopic polypectomy in both our hospitals and at other hospitals from April 2003 and April 2010. These patients were divided into two groups, the group (non-operation group) that only underwent a polypectomy (n = 37) and the group (operation group) that underwent a polypectomy with subsequent surgery (n = 33). RESULTS: There were no differences between two groups in the ratios of the number of men to the number of women, the ages or the comorbidities. In terms of endoscopic findings, we found no differences between the two groups in the locations of the polyps, the sizes of the polyps, or the presence of stalks. However, ulceration of polyps was higher in the non-operation group (51.5% vs. 21.6%; P = 0.009), as was the case with submucosal invasion (75.8% vs. 16.2%; P < 0.005). When an endoscopic polypectomy was performed, incomplete resection margins and specimens with margins involved occurred more frequently in the operation group (93.9% vs. 51.4%; P < 0.005), but no residual tumor was detected in 31 of 33 (93.9%) patients in that group. One pathologist reviewed the specimens of 54 patients (operation group, 19; non-operation group, 36). Six of the 19 polyps (31.6%) in the operation group and fifteen of the 36 polyps (41.7%) in the non-operation group had a margin without cancer cells. CONCLUSION: We may accept the criterion of a safe margin, including a coagulation zone. A multidisciplinary approach has to be developed by surgeons, endoscopists and pathologists based on a discussion of the risk factors for the patient before making a decision on the treatment treatment.

Vancomycin Pharmacokinetics in Oliguric Patients Undergoing Continuous Venovenous Hemodialysis and Continuous Venovenous Hemodiafiltration / 대한신장학회지

PURPOSE: Critically ill patients receiving continuous renal replacement therapy are susceptible to infection with methicillin-resistant bacteria, which require treatment with vancomycin. However, there are limited reports regarding vancomycin pharmacokinetics in the continuous venovenous hemodialysis (CVVHD) and continuous venovenous hemodiafiltration (CVVHDF). We performed this study to investigate the pharmacokinetics of vancomycin in oliguric patients receiving CVVHD and CVVHDF. METHODS: Data at steady-state obtained as part of our routine drug monitoring of vancomycin therapy in critically ill adult oliguric patients undergoing CVVHD or CVVHDF, retrospectively. Data were available for 35 cases of 23 patients assessed for 2 years. We analyzed the pharmacokinetic parameters of these cases. RESULTS: 8 cases on CVVHD and 27 cases on CVVHDF were available. The mean intensity of CVVHD was 17.7+/-4.9 mL/hour/kg and that of CVVHDF was 32.1+/-3.9 mL/hour/kg (p=0.000). The mean clearance of vancomycin was 16.4+/-3.8 mL/min in the CVVHD group and 21.6+/-5.1 mL/min in the CVVHDF group (P=0.007). The elimination of vancomycin correlated with the intensity of CVVHD and CVVHDF (CVVHD; r2=0.745, p=0.012, CVVHDF; r2=0.452, p=0.000). CONCLUSION: CVVHD and CVVHDF are effective for vancomycin elimination and there is a strong dependency of the vancomycin removal on the intensity of continuous renal replacement therapy. Strategies for individualization of vancomycin therapy in patients receiving CVVHD and CVVHDF are proposed.

Posterior Reversible Encephalopathy Syndrome in a Patient with Lupus Nephritis / 대한류마티스학회지

Posterior reversible encephalopathy syndrome (PRES) has been described in various clinical settings, including severe hypertension, eclampsia, lupus and immunosuppressive therapy. We report a 27 year-old female systemic lupus erythematosus patient who developed severe headache, seizure and hemiparesis during her lupus nephritis flare. Magnetic resonance image (MRI) showed multi-focal high signal intensity lesions in the parieto-occipital cortex bilaterally and in the subcortical white matter. Her condition improved with immunosuppressive treatments, antihypertensives and hemodialysis. The extent of her lesions decreased on follow-up MRI 2 months later. This case suggests that PRES can be treated with immunosuppressive drugs that do not increase blood pressure.

Hyperventilation delays clinical induction of desflurane

BACKGROUND: Ventilation is a major determinant of the alveolar concentration of inhaled anesthetics. Hyperventilation accelerates the equilibration of anesthetic in the lungs, but decelerates it in the brain. We evaluated this phenomenon for desflurane. METHODS: Twenty healthy subjects were enrolled after IRB approval. End-tidal concentrations of desflurane (P.DESF) were recorded during 10 minutes of mask induction with 8% desflurane. P.DESF was modeled with time and end-tidal concentrations of CO2 (P.ETCO2) using a two-exponential pharmacokinetic equation. Bispectral index (BIS) values were also measured to find out the component reflecting the cerebral concentration of desflurane. RESULTS: During induction, the rise of P.DESF could be separated into two components: early and late rises. Individual BIS values showed a higher correlation with the late component of P.DESF (P = 0.000). P.ETCO2 had two different effects on the rise of P.DESF. CONCLUSIONS: Hyperventilation hastened the early rise and delayed the late rise of P.DESF (P = 0.00, P = 0.00). Hyperventilation should be avoided to obtain rapid anesthesia induction with desflurane.