Objectives: This study analyzed the clinical outcomes of remdesivir treatment in coronavirus disease 2019 (COVID-19) patients in South Korea. Methods: This retrospective cohort study involved the secondary analysis of epidemiological data. Among patients diagnosed with COVID-19 from July 2, 2020 to March 23, 2021 (12 AM), 4,868 who received oxygen therapy and were released from isolation after receiving remdesivir treatment were assigned to the treatment group, and 6,068 patients who received oxygen therapy but not remdesivir were assigned to the untreated group. The study subjects included children under the age of 19. The general characteristics and severity were compared between the groups. Differences in the time to death and mortality were also compared. Results: In the untreated group, the hazard ratio [HR] for mortality was 1.59 (95% confidence interval [CI], 1.40–1.80) among patients aged ≥70 years and 2.32 (95% CI, 2.00–2.69) in patients with severe disease in comparison to the treatment group. In a comparison of survival time among patients with severe disease aged ≥70 years, the HR for mortality before 50 days was 2.09 (95% CI, 1.77–2.46) in the untreated group compared to the treatment group. Conclusion Patients with remdesivir treatment showed better clinical outcomes in this study, but these results should be interpreted with caution since this study was not a fully controlled clinical trial.

BACKGROUND: Korean national cancer screening program selected fecal occult blood test (FOBT) as a primary screening method of colorectal carcinoma in adult > or =50 yr old irrespective of symptom. Notice to pre-analytical errors is especially important for the FOBT because examinees collect and submit their specimens to laboratories by themselves. We examined the influences of the fecal storage temperatures, durations and with or without buffer on the FOBT results. METHODS: Thirty FOBT-positive specimens above 100 ng/mL were used for the study from July to August 2008. Quantitative FOBT was performed with OC-sensors II (Eiken Chemical Co., Japan). Each specimen was divided into 4 groups. Two groups in plastic buffer-free containers were kept either at 4degrees C or room temperature (25-28degrees C), respectively. Another two groups in buffer-tubes were also kept either at 4degrees C or room temperature. Each group was repeatedly examined with same method every 24 hr up to 120 hr. RESULTS: Eleven specimens (36.7%) in buffer-free containers converted to negative results (below the 100 ng/mL) after 24 hr and 17 specimens (56.7%) did after 48 hr at room temperature. Ten specimens (33.3%) in buffer-free containers converted to negative after 48 hr at 4degrees C. Specimens contained in buffer-tubes showed little change; 3 specimens (10.0%) at room temperature and no specimen at 4degrees C showed negative conversions after 48 hr. CONCLUSIONS: Buffer-tube minimizes false negative FOBT results during pre-analytical delay of specimen. The examinees using buffer-free containers need to be educated to hand in their specimens to laboratories as soon as possible.
Buffers ; Colorectal Neoplasms/*diagnosis ; Humans ; Middle Aged ; *Occult Blood ; *Specimen Handling ; Temperature ; Time Factors

OBJECTIVES: The aim of this study was to evaluate the roles of cigarette smoking, alcohol consumption, tuberculosis, and their interactions in the risk of lung cancer in a Korean cohort. METHODS: The study subjects comprised 13,150 males and females aged above 20 years old. During the follow up period from 1993 to 2002, 79 lung cancer cases were identified by the central cancer registry and the national death certificate database. Information on cigarette smoking, alcohol consumption and the history of physiciandiagnosed tuberculosis was obtained by interview. Indirect chest X-ray findings were also evaluated to ascertain tuberculosis cases. Cox proportional hazard models were used to estimate relative risks (RR) and 95% confidence intervals (CI) after adjusting for age and gender. RESULTS: Cigarette smoking was statistically significantly associated with an increased risk of lung cancer [for current smokers, RR = 2.33 (95% CI = 1.23 - 4.42) compared to non-smokers]. After further adjustment for cigarette smoking, both alcohol consumption and tuberculosis showed no statistically significant association with the risk of lung cancer [for current drinkers, RR = 0.80 (95% CI = 0.48 - 1.33) compared to non-drinkers] [for tuberculosis cases, RR = 1.17 (95% CI = 0.58 - 2.36) compared to noncases]. There was no statistically significant interaction between cigarette smoking and alcohol consumption (pinteraction = 0.38), or cigarette smoking and tuberculosis (p-interaction = 0.74). CONCLUSIONS: Although cigarette smoking was confirmed as a risk factor of lung cancer in this cohort study, this study suggests that alcohol consumption and tuberculosis may not be associated with the risk of lung cancer.
Adult ; Aged ; Alcohol Drinking/*adverse effects ; Cohort Studies ; Educational Status ; Female ; Humans ; Korea/epidemiology ; Lung Neoplasms/epidemiology/*etiology ; Male ; Middle Aged ; Proportional Hazards Models ; Smoking/*adverse effects ; Tuberculosis, Pulmonary/*complications

This article was published with an error.

BACKGROUND/AIMS: In Korea, hepatitis C is included as an infectious disease in a sentinel surveillance system. Recently, a large variation in hepatitis C incidence between different regions in Korea has been noticed. The current study verified the nationwide distribution of hepatitis C infection for effective prevention and management. METHODS: We counted the number of hepatitis C patients who visited a hospital per county using the National Health Insurance database from 2007 to 2011. The age-adjusted prevalence ratio was used, and the age adjustment method was used as an indirect standardization method. Disease mapping and spatial analysis were conducted using a geographic information system. RESULTS: The annual prevalence of diagnosed hepatitis C was approximately 0.12% to 0.13% in Korea. The age-adjusted prevalence ratios in Busan, Jeonnam, and Gyeongnam were high (1.75, 1.4, and 1.3, respectively). The three regions in the southern coastal area of the Korean Peninsula were identified as a high-prevalence cluster (Moran's index, 0.3636). CONCLUSIONS: The present study showed that hepatitis C infection has very large regional variation, and there are several high-risk areas. Preventive measures focusing on these areas should be applied to block the transmission of hepatitis C and reduce the disease burden.
Adult ; Age Distribution ; Aged ; Hepatitis C, Chronic/*epidemiology ; Humans ; Middle Aged ; Prevalence ; Republic of Korea/epidemiology ; Residence Characteristics ; Risk Factors

PURPOSE: This study was carried out to predict the mortality rate for gastric cancer up to 2020 in Korea with forecasting model. METHODS: The trends of the age-adjusted mortality rate was calculated from 1983 to 2003 using the mortality data of the past 20 years in Korea, and projected up to the year of 2020 with log-linear models for each gender. The number of deaths from gastric cancer was calculated from the predicted mortality rate. RESULTS: Age-adjusted mortality rates for gastric cancer per 100,000 persons were 32.13 in 1983, 23.95 in 1990, and 15.99 in 2003 for women, and 70.37, 58.74, 41.04 for men, respectively. The expected age-adjusted mortality rates for gastric cancer were 16.50 in 2005, 14.27 in 2010, and 10.66 in 2020 for women, and 39.14, 33.83, 25.28 for men, respectively. In contrast to this decreasing trend, it is predicted that mortality rates for those aged 75 or over would increase steadily. The predicted number of deaths from gastric cancer was 6,519 for women and 13,743 for men in 2020. CONCLUSIONS: This study suggests that gastric cancer mortality rate would decrease continuously except for some aged groups. The declining trends in gastric cancer mortality are regarded as a result of lifestyle changes, improvements in screening methods and treatments. Strategies for aged groups should be developed in order to control increasing mortality rates.
Female ; Forecasting ; Humans ; Korea* ; Life Style ; Linear Models ; Male ; Mass Screening ; Mortality* ; Stomach Neoplasms*

PURPOSE: Cancer has been the leading cause of deaths since 1980s in Korea. Among them, colorectal cancer and breast cancer shows steadily increasing pattern, being the fourth and the fifth common site of cancer death in Korea, respectively. This analysis aimed to evaluate potential contribution of birth cohort effects to the recent increases in mortality of colorectal cancer and breast cancer since 1983 in Korea. METHODS: Mortality statistics on deaths of both cancers for the past 20 years of 1983~2002 were obtained from the National Statistical Office. The age-standardized mortality rates were calculated based on the census population of 1992 as a standard. RESULTS: Age-standardized mortality rate for colorectal cancer increased 4.7-fold in men and 3.6-fold in women, whereas 2.1-fold increase in breast cancer mortality during 1983~2002. Age-specific mortality rates for colorectal cancer were steadily increasing by age before 1991 in both genders. However, the mortality rates showed an exponentially increasing pattern for the age group of 70 and over during 1993~2001, which was more prominent in female. The birth cohort curves showed that there were 2- to 3-fold increases in the mortality rates of people who were born in 1931 for colorectal cancer compared to those of people who were born in 1921. Differences in mortality for breast cancer by birth cohort were 1.7-fold among age group of 45~49 and 50~54 between 1936 and 1946. CONCLUSIONS: This analysis suggests that recent increases in mortality of colorectal cancer and breast cancer could potentially be due to birth cohort effects, i.e. rapid changes in life-style in younger generation. The quantitative approach using age-period-cohort model should be pursued.
Breast Neoplasms* ; Breast* ; Cause of Death ; Censuses ; Cohort Effect* ; Cohort Studies* ; Colorectal Neoplasms* ; Female ; Humans ; Korea* ; Male ; Mortality* ; Parturition*

BACKGROUND: The cases of Plasmodium vivax malaria in Korea are mixed with long and short incubation periods. This study aims to define clinico-epidemiologic chracteristcs of Plasmodium vivax malaria in Korea. MATERIALS AND METHODS: We selected the civilian cases infected with P. vivax malaria in Korea from the epidemiological investigation data of 2001 to 2010, whose incubation periods could be estimated. The long and short incubation periods were defined by duration of infection and onset time, and the cases were compared by demographic factors and clinical symptom, infection and onset time. The correlation was analyzed between the proportion of cases in the infected region with the long incubation period and meteorological factors along with latitude. RESULTS: The length of the mean short and long incubation periods for the cases were 25.5 days and 329.4 days, respectively. The total number of the study subjects was 897, and the number cases of short and long incubation periods was 575 (64.1%) and 322 (35.9%), respectively. The aspect of incubation period showed a significant difference by region of infection; there was a higher proportion of long incubation period infection cases in Gangwon-do than in Gyeonggi-do and Incheon. The proportion of long incubation period cases showed significant correlation with latitude and temperature of August and September of the infected regions. CONCLUSIONS: Incubation period of P. vivax malaria in Korea showed significant difference by infected region, infection and onset time and the proportion of long incubation period cases showed significant correlation with latitude and meteorological factors of the infected regions.
Demography ; Korea ; Malaria ; Malaria, Vivax ; Meteorological Concepts ; Plasmodium ; Plasmodium vivax

Objectives: Real-time polymerase chain reaction is currently used as a confirmatory test for coronavirus disease 2019 (COVID-19). The test results are interpreted as positive, negative, or inconclusive, and are used only for a qualitative classification of patients. However, the test results can be quantitated using threshold count (Ct) values to determine the amount of virus present in the sample. Therefore, this study investigated the diagnostic usefulness of Ct results through various quantitative analyzes, along with an analysis of clinical and epidemiological characteristics. Methods: Clinical and epidemiological data from 4,642 COVID-19 patients in April 2021 were analyzed, including the Ct values of the RNA-dependent RNA polymerase (RdRp), envelope (E), and nucleocapsid (N) genes. Clinical and epidemiological data (sex, age, underlying diseases, and early symptoms) were collected through a structured questionnaire. A correlation analysis was used to examine the relationships between variables. Results: All 3 genes showed statistically significant relationships with symptoms and severity levels. The Ct values of the RdRp gene decreased as the severity of the patients increased. Moreover, statistical significance was observed for the presence of underlying diseases and dyspnea. Conclusion Ct values were found to be related to patients’ clinical and epidemiological characteristics. In particular, since these factors are closely related to symptoms and severity, Ct values can be used as primary data for predicting patients’ disease prognosis despite the limitations of this method. Conducting follow-up studies to validate this approach might enable using the data from this study to establish policies for preventing COVID-19 infection and spread.

Purpose: In response to the surge in coronavirus disease 2019 (COVID-19) omicron variant cases, we have implemented preemptive testing for preschool and school. The purpose is to quickly detect COVID-19 cases using a rapid antigen test (RAT) kit so that normal school activities can continue. Methods: The results entered in The Healthcare Self-Test App were merged with the information on the status of confirmed cases in the COVID-19 Information Management System by Korea Disease Control and Prevention Agency (KDCA) for preschool and school of students and staffs March 2 to May 1, 2022 to analyze the RAT positive rate and positive predictive value of RAT. Results: In preschool and school 19,458,575 people were tested, weekly RAT positive rate ranged from 1.10% to 5.90%, positive predictive value of RAT ranged from 86.42% to 93.18%.By status, RAT positive rate ranged from 1.13% to 6.16% for students, 0.99% to 3.93% for staffs, positive predictive value of RAT ranged from 87.19% to 94.03% for students, 77.55% to 83.10% for staffs. RAT positive rate by symptoms ranged from 76.32% to 88.02% for those with symptoms and 0.34% to 1.11% for those without symptoms. As a result of preschool and school RAT, 943,342 confirmed cases were preemptively detected, before infection spread in preschool and school. Conclusions RAT was well utilized to detect confirmed cases at an early stage, reducing the risk of transmission to minimize the educational gap in preschool and school. To compensate for the limitations of RAT, further research should continue to reevaluate the performance of RAT as new strains of viruses continue to emerge. We will have to come up with various ways to utilize it, such as performing periodic and repeated RAT and parallel polymerase chain reaction.