Background: Dengue fever is considered one of the transfusion-transmissible emerging infectious diseases. Dengue fever has been reported every year by the Korea Disease Control and Prevention Agency (KDCA). Because a blood donor screening assay to detect the dengue virus (DENV) as an agent of dengue fever is not performed, the risk of transfusion-transmitted DENV infection needs to be assessed. Methods: This study collected the data of DENV infected cases from the Infectious Disease Portal of the KDCA, the data of blood donors and blood components from the Blood Information Management System of the Korean Red Cross, and the data of travelers to major dengue outbreak countries from the Korean Tourism Organization.All data were from 2016 to 2018. A risk assessment was performed using European Up-Front Risk Assessment Tool (EUFRAT). Results: The risk of DENV-infected red cells and platelet concentrate was higher than that of plasma and apheresis platelet. Nevertheless, the risk of the DENV infected blood component was shown to be less than one case per year for all kinds of blood components. Conclusion All the DENV infected cases in Korea were overseas travelers. Therefore, the risk of transfusiontransmissible DENV infection is very low. On the other hand, continuous observation and monitoring are required because Aedes albopictus as a vector of DENV is found in Korea, and the increase in reported cases may lead to domestic infections.

Background: Dengue fever is considered one of the transfusion-transmissible emerging infectious diseases. Dengue fever has been reported every year by the Korea Disease Control and Prevention Agency (KDCA). Because a blood donor screening assay to detect the dengue virus (DENV) as an agent of dengue fever is not performed, the risk of transfusion-transmitted DENV infection needs to be assessed. Methods: This study collected the data of DENV infected cases from the Infectious Disease Portal of the KDCA, the data of blood donors and blood components from the Blood Information Management System of the Korean Red Cross, and the data of travelers to major dengue outbreak countries from the Korean Tourism Organization.All data were from 2016 to 2018. A risk assessment was performed using European Up-Front Risk Assessment Tool (EUFRAT). Results: The risk of DENV-infected red cells and platelet concentrate was higher than that of plasma and apheresis platelet. Nevertheless, the risk of the DENV infected blood component was shown to be less than one case per year for all kinds of blood components. Conclusion All the DENV infected cases in Korea were overseas travelers. Therefore, the risk of transfusiontransmissible DENV infection is very low. On the other hand, continuous observation and monitoring are required because Aedes albopictus as a vector of DENV is found in Korea, and the increase in reported cases may lead to domestic infections.

BACKGROUND: Because of a lack of substances for platelet (PLT) metabolism and preservation, normal saline (NS) washed PLTs can only be stored for short lengths of time. However, the use of platelet additive solutions (PAS) could help solve this problem. In this study, the in vitro quality of NS washed platelets (wPLTs) stored in two types of PAS were compared with those of wPLTs stored in NS. METHODS: Five units of NS washed apheresis platelets were pooled aseptically and separated into five aliquots for storage in NS only as well as T-PAS+ (Terumo BCT, Lakewood, CO, USA) and CompoSol PS (Fenwal, Lake Zurich, IL, USA) with or without 15 mM glucose. The parameters of wPLTs quality were assessed up to 48 hrs after washing and the whole experiment was repeated 10 times independently. RESULTS: wPLTs in two kinds of PAS had better quality than wPLTs in NS, and wPLTs in T-PAS+ showed better quality than those in CompoSol PS. PAS-stored wPLTs with added glucose maintained stable CD62P and Annexin V expression during storage, but exhibited increased lactate accumulation. Evaluation of in vitro quality revealed that all wPLTs had a rating of 4 immediately after washing. However, only T-PAS+-stored wPLTs with glucose maintained a rating of 4 up to 48 hrs of post-washing. CONCLUSION: Using PAS storage for wPLTs may be beneficial compared to NS. The results presented herein suggest that T-PAS+ containing glucose has the potential to extend storage time by up to 48-hours.
Annexin A5 ; Blood Component Removal ; Blood Platelets* ; Blood Preservation ; Glucose ; In Vitro Techniques ; Lactic Acid ; Lakes ; Metabolism

OBJECTIVES: This study aimed to examine the effects of unemployment on health-related behavioral changes and worker's health, and to produce the basic data that is needed to formulate the necessary measures for reducing the health hazards and social costs caused by unemployment. METHODS: A questionnaire survey was conducted with a group of 123 people who had lost their jobs due to structural unemployment (the unemployment group) and with a group of 155 employed people (the employment group). The 36-Item Short-Form Health Survey (SF-36) was used as a tool for evaluating the demographic characteristics, the health-related behaviors and the health level. RESULTS: Irregular mealtimes and increased smoking and drinking rates were observed in the unemployment group (P<0.05). The results of the logistic regression analysis that was conducted after correcting for the confounding variable showed that in the unemployment group, unlike in the employment group, the odds ratio of the group with a low health level score on the SF-36 has a significant difference in "Role limitation resulting from physical problems" (OR 2.20, 95% CI=1.01~4.78), "Role limitation resulting from emotional problems" (OR 4.51, 95% CI=1.90~10.69) and "Mental health" (OR 3.43, 95% CI=1.52~7.74) among the eight lower areas. CONCLUSIONS: Unemployment causes a negative change in health-related behaviors and lower levels of mental and physical health. Systematic research must be conducted to promote good health among unemployed workers and to reduce their social costs.
Confounding Factors (Epidemiology) ; Drinking ; Employment ; Hazardous Substances ; Health Behavior ; Health Status ; Health Surveys ; Logistic Models ; Meals ; Odds Ratio ; Quality of Life ; Questionnaires ; Smoke ; Smoking ; Unemployment

Analysis of HCV genotypes can help identify infection routes and the development of treatment methods. However, in some samples with a low titer of HCV RNA, it is difficult to analyze their genotypes. In our previous study about HCV genotyping, we could not identify 12 cases among the 175 HCV NAT reactive samples due to their low titer. In this study, we adopted three different kinds of virus concentration methods to identify the genotypes of the 12 unidentified cases and compared their efficacy. The three virus concentration methods were automatic nucleic acid extraction, polyethyleneimine-magnetic bead-based extraction, and sucrose cushion ultracentrifugation. After virus concentration using every three methods, we analyzed HCV RNA genotypes using the concentrated sample of the best efficacy. Among the 12 cases, six were identified as 1b, four as mixed types, and two were unidentified. Here we could validate that the sample concentration method is useful to identify the HCV genotypes, especially in samples with low HCV RNA titers. Furthermore, considering the convenience, high efficacy, and time-saving, automatic nucleic acid extraction is considered the most useful concentration method for samples with titer lower than 50 IU/mL.

There were 10 cases of transfusion-transmitted P. vivax malaria from 1990 to 2021. The Korean Centers for Disease Control and Prevention (KCDC) designated the areas showing a high frequency of malaria as a malaria-endemic area and has restricted whole blood donation from these areas. While the number of malaria infections has declined in recent years, the blood inventory has declined sharply due to the COVID-19 pandemic. Accordingly, the Ministry of Health and Welfare temporarily approved the donation of whole blood from malaria-endemic areas to secure the supply of blood products. In the present study, an anti-malaria screening and nucleic acid amplification test (NAT) was performed on samples collected from the malaria-endemic areas from May 20 to June 30, 2020. A total of 14,741 samples were collected and tested. NAT was performed for 1096 runs to test all the collected samples. The 117 (0.79%) samples showed initial reactive results due to the contamination of abnormal PCR results. Negative results were obtained for the samples showing initial reactive results using a duplicated re-test. From the NAT tests, no sample showed a true positive result. The results of the malaria antibody screening test were reactive in 10 out of the 14,741 samples. The malaria antibody screening needs to be reviewed through further study because of its insufficient sensitivity and specificity. According to this study, excluding the 10 reactive malaria antibodies, additional blood components could be secured from 14,731 blood donors for a stable blood supply.

Analysis of HCV genotypes can help identify infection routes and the development of treatment methods. However, in some samples with a low titer of HCV RNA, it is difficult to analyze their genotypes. In our previous study about HCV genotyping, we could not identify 12 cases among the 175 HCV NAT reactive samples due to their low titer. In this study, we adopted three different kinds of virus concentration methods to identify the genotypes of the 12 unidentified cases and compared their efficacy. The three virus concentration methods were automatic nucleic acid extraction, polyethyleneimine-magnetic bead-based extraction, and sucrose cushion ultracentrifugation. After virus concentration using every three methods, we analyzed HCV RNA genotypes using the concentrated sample of the best efficacy. Among the 12 cases, six were identified as 1b, four as mixed types, and two were unidentified. Here we could validate that the sample concentration method is useful to identify the HCV genotypes, especially in samples with low HCV RNA titers. Furthermore, considering the convenience, high efficacy, and time-saving, automatic nucleic acid extraction is considered the most useful concentration method for samples with titer lower than 50 IU/mL.

There were 10 cases of transfusion-transmitted P. vivax malaria from 1990 to 2021. The Korean Centers for Disease Control and Prevention (KCDC) designated the areas showing a high frequency of malaria as a malaria-endemic area and has restricted whole blood donation from these areas. While the number of malaria infections has declined in recent years, the blood inventory has declined sharply due to the COVID-19 pandemic. Accordingly, the Ministry of Health and Welfare temporarily approved the donation of whole blood from malaria-endemic areas to secure the supply of blood products. In the present study, an anti-malaria screening and nucleic acid amplification test (NAT) was performed on samples collected from the malaria-endemic areas from May 20 to June 30, 2020. A total of 14,741 samples were collected and tested. NAT was performed for 1096 runs to test all the collected samples. The 117 (0.79%) samples showed initial reactive results due to the contamination of abnormal PCR results. Negative results were obtained for the samples showing initial reactive results using a duplicated re-test. From the NAT tests, no sample showed a true positive result. The results of the malaria antibody screening test were reactive in 10 out of the 14,741 samples. The malaria antibody screening needs to be reviewed through further study because of its insufficient sensitivity and specificity. According to this study, excluding the 10 reactive malaria antibodies, additional blood components could be secured from 14,731 blood donors for a stable blood supply.

BACKGROUND: For donor samples showing reactive results in a human T-cell lymphotropic virus (HTLV) antibody test along with indeterminate results in Western blot assay, HTLV nucleic acid amplification test using laboratory-developed polymerase chain reaction (PCR) was performed. It is necessary to construct an adequate internal control (IC) to evaluate the accuracy of the results since we did not use an IC in the laboratory-developed PCR. METHODS: As a competitive IC, plasmid DNA containing the primer recognition sequence for amplification of the HTLV pX region was constructed. We determined the adequate concentration of the IC, which was added to the samples to evaluate the accuracy of the test results. RESULTS: When the plasmid DNA was added to the HTLV-positive samples, the amplified product of IC (400 bp) was detected with the HTLV gene (230 bp). The adequate concentration of plasmid DNA added as an IC was 1 pg. CONCLUSION: The construction of plasmid DNA as a competitive IC is an efficient method to evaluate accuracy of the test results. However, the production process for the competitive IC must be further developed. Therefore, it is necessary to compare with the performance of a non-competitive IC.
Blotting, Western ; DNA ; Humans ; Methods ; Nucleic Acid Amplification Techniques ; Plasmids ; Polymerase Chain Reaction* ; T-Lymphocytes ; Tissue Donors

HBV core antibody and surface antibody test are currently conducted for those donors showing non-discriminated reactive (NDR) results on a nucleic acid amplification test (NAT) as a blood donor screening assay. It is necessary to investigate the relationship with HCV or HIV in the donors showing NDR results. From June 12th, 2012 to December 31st, 2018, 0.05% (9,020/17,798,461) donors showed NDR results on a NAT. Among the donors showing NDR results, 17 and 18 donors showed positive results on serological assay of HCV and HIV, respectively. 23 donors with NDR results showed positive results on the serological assay or NAT for HCV or HIV on the following donation. Further study and more accumulated data are required because it may be difficult to find the cause of NDR results by the current serological assay that is used for screening blood donors.
Blood Donors ; HIV ; Humans ; Mass Screening ; Nucleic Acid Amplification Techniques ; Tissue Donors