Establishment and application of sandwich ELISA for detection of specific antigen of Seoul virus L99 strain / 中华微生物学和免疫学杂志

Objective:To establish a double antibody sandwich ELISA for detecting the specific antigen of Seoul virus (SEOV) L99 strain and to provide a means for antigen detection in the development, production and verification of vaccine against hemorrhagic fever with renal syndrome (HFRS).Methods:Monoclonal antibodies (McAbs) aganist L99 virus were induced in mice using four hybridoma cell lines and purified by Protein-A affinity chromatography. The purity, titer and specificity of McAbs were determined by SDS-PAGE, indirect ELISA and Western blot, respectively. Four McAbs were paired with each other and the additivity indices of paired McAbs were analyzed. After labeling McAbs with horseradish peroxidase (HRP), the concentrations of the coated and labeled antibodies were optimized by orthogonal test, and then a double antibody sandwich ELISA for virus antigen detection was established. Type Ⅱ HFRS inactivated vaccine standard was used as a quantitative standard to verify the sensitivity, linearity, specificity, accuracy and precision of the developed method. The applicability of the method was verified by testing three batches of vaccine stock solutions.Results:Four McAbs were at titers of greater than 1∶10 6 and their purity was all greater than 98%. The McAbs secreted by 1D5, 3A4 and 5B7 cells could specifically recognize the nucleocapsid protein of SEOV L99. There was cross-reaction between McAb secreted by 1D5 cells and Hantaan virus PS-6. The McAbs secreted by 3A4 and 1D5 were used as coating and labeling antibodies based on the results of antibody pairs. The working concentrations of the coating antibody and the horseradish peroxidase (HRP)-labeled antibody were 20 μg/ml and 1∶4 000, respectively. The minimum detection limit of the established method for the detection of SEOV L99 antigen was 0.078 1 μg/ml, and the linear range was 0.078 1-2.500 0 μg/ml with a R2 value of more than 0.99. There was no cross reaction with other HFRS vaccine. The virus antigen recovery rate was between 95.8% and 108.7%, and the coefficients of variation of precision was less than 10%. Three batches of Type II HFRS inactivated vaccine stocks were detected by this method and the results was dose-dependent. Conclusions:This study successfully established a double antibody sandwich ELISA method for specific detection of SEOV L99 strain antigen in the production of bivalent HFRS vaccines produced from hamster kidney cells.

Antibodies Against Seoul Hantavirus in Brown rats (Rattus norvegicus) from Grenada, West Indies

Hantavirus is an emerging zoonotic virus, cause of fatal diseases in humans. Brown rats (Rattus norvegicus) are known reservoir host for Seoul hantavirus. This is the second report of prevalence of antibodies against hantavirus in brown rats in Grenada. Sera from 169 brown rats were tested using ELISA for antibodies against hantavirus. Prevalence of antibodies was found in 47 rats (27.5%). There was no significant difference related to age and sex of seropositive rats. Although no case of hantavirus infection in humanshas been recorded in Grenada, the presence of moderate infection in reservoir host should be considered a risk factor for disease transmissi on in humans.

Our Hantaan Virus Became a New Family, Hantaviridae in the Classification of Order Bunyavirales. It will Remain as a History of Virology

In February 2019, the order Bunyavirales, previously family Bunyaviridae, was amended by new order of 10 families including Hantaviridae family, and now accepted by the International Committee on Taxonomy of Viruses (ICTV). Hantaviridae is now a family of the order Bunyavirales, and the prototype virus species is Hantaan orthohantavirus. The family Hantaviridae is divided into four subfamilies including Mammantavirinae, Repantavirinae, Actantavirinae and Agantavirinae. The subfamily Mammantavirinae is divided into four genera including Orthohantavirus, Loanvirus, Mobatvirus and Thottimvirus. The four Hantavirus species have been found in Korea including three Orthohantaviruses (Hantaan orthohantavirus, Seoul orthohantavirus and Jeju orthohantavirus) and one Thottimvirus (Imjin thottimvirus).

Assessment of relationship between the use of household products and atopic dermatitis in Seoul: focused on products with associated risks

The purpose of this study was to evaluate the relationship between the use of certain household products (HPs) at home and atopic dermatitis (AD) in adults. The study was conducted on 1,500 households in Seoul, South Korea. We obtained information on general characteristics, the use of HPs, and AD through an online panel survey in July 2018. HPs were selected as 23 kinds of products with associated risks that are management targets of the Ministry of Environment. The international study of asthma and allergies in childhood was used for the AD questionnaires. Logistic regression analysis was used to identify AD affected by the use of HPs. Average number of used HPs was 13.44 out of 23, and average usage frequency of HPs was 3.52 times a month at home in Seoul for the last 1 year. Compared with subjects with a low number of HPs used (reference), subjects with a high number of used HPs (4th quartile) were more likely to have lifetime diagnosis of AD (odds ratio (OR) = 1.77, 95% confidence interval (CI); 1.23-2.54), symptoms of AD in the last 12 months (OR = 2.66, 95% CI; 1.92-3.70), and treatment of AD in the last 12 months (OR = 2.37, 95% CI; 1.48-3.80). Compared with subjects with a low HPs usage frequency (reference), subjects with a high HPs usage frequency (4th quartile) were more likely to have lifetime diagnosis of AD (OR = 1.88, 95% CI; 1.31-2.70), symptoms of AD in the last 12 months (OR = 2.14, 95% CI; 1.54-2.96), and treatment of AD in the last 12 months (OR = 2.23, 95% CI; 1.39-3.60). Therefore, the use of HPs was significantly associated with AD. The findings of this study might be useful as basic data for managing allergic diseases and establishing preventive measures.

Why is Life Expectancy in Busan Shorter than in Seoul? Age and Cause-Specific Contributions to the Difference in Life Expectancy between Two Cities

PURPOSE: Seoul and Busan are the two largest cities in Korea. However, life expectancy (LE) in Busan is shorter than in Seoul and among the total Korean population. This study was conducted to decompose age- and cause-specific contributions to the LE difference between Seoul and Busan. MATERIALS AND METHODS: We obtained population and mortality data for Seoul and Busan between 2015 and 2017 from Statistics Korea. We applied Arriaga's decomposition method to life table data to estimate age- and cause-specific contributions to the LE difference between Seoul and Busan. RESULTS: During 2015–2017, LE in Busan was shorter than in Seoul by 2.22 years. Roughly two-thirds of the LE gap between Seoul and Busan was due to excess mortality among elderly people in Busan. The ≥85 age group alone contributed to approximately 20% of the LE gap, while no meaningful contribution was made by the 1–24 age groups. Cardiovascular disease accounted for over 40% of the total LE gap between Seoul and Busan, and this factor was more prominent in women. The top 15 leading specific causes of deaths explained nearly the entire LE difference between Seoul and Busan. CONCLUSION: The difference in LE between Seoul and Busan was due to higher mortality rate in Busan than in Seoul, especially in the elderly population and from cardiovascular diseases. Information on age- and cause-specific contributions to the LE difference between Seoul and Busan may guide health policy-makers to plan strategies for reducing the gap in LE.

Cognition enhancing effect of panax ginseng in Korean volunteers with mild cognitive impairment: a randomized, double-blind, placebo-controlled clinical trial

This study aimed to investigate the cognition-enhancing effect of Panax ginseng. A randomized, double-blind, placebo-controlled clinical trial was conducted to address the cognition-enhancing effects of Panax ginseng. A total of 90 Korean volunteers with mild cognitive impairment participated in this study. All subjects were allocated randomly into ‘Ginseng’ group or ‘Placebo’ group. All subjects were administered 3g of Panax ginseng powder or starch (placebo) for 6 months. The Korean version of the Mini-Mental Status Examination (K-MMSE), Korean version of Instrumental Activities of Daily Living (K-IADL), and Seoul Neuropsychological Screening Battery (SNSB) were used to assess the changes in cognitive function at the end of the 6 month study period. The subjects of the ‘Ginseng’ group improved significantly on the Rey Complex Figure Test (RCFT) immediate recall (P = 0.0405 and P = 0.0342 in per-protocol (PP) and intention-to-treat (ITT) analysis, respectively) and on the RCFT 20-min delayed recall (P = 0.0396 and P = 0.0355 in PP and ITT analysis, respectively) compared with ‘placebo’ group throughout the 6 months of Panax ginseng administration. There were no serious adverse events. These results suggest that Panax ginseng has a cognition-enhancing effect.

Comparison of Services for Autism Spectrum Disorder in Massachusetts with Those in Seoul

BACKGROUND: This article intended to identify and describe areas in need of services and interventions for individuals with autism spectrum disorder (ASD) and their families in Seoul, Korea. METHODS: A descriptive comparison was made between available services and interventions in Seoul, Korea and Massachusetts, USA. Relevant information was obtained through sending phone/email inquiries to the governments and organizations, visiting their official websites, and searching for published articles or reports. RESULTS: In a few areas such as level of education, economy, and general quality of healthcare, Seoul was found to be similar to Massachusetts. However, in terms of services and interventions for individuals with ASD and their families, especially early identification and intervention, special education, care coordination, school-based programs, and transition to adulthood, Massachusetts was shown to have far more availability. CONCLUSION: The limited availability of services and interventions for individuals with ASD and their families in Seoul in comparison to Massachusetts, underlines target areas for further investment and development.

Assessment of relationship between the use of household products and atopic dermatitis in Seoul: focused on products with associated risks

The purpose of this study was to evaluate the relationship between the use of certain household products (HPs) at home and atopic dermatitis (AD) in adults. The study was conducted on 1,500 households in Seoul, South Korea. We obtained information on general characteristics, the use of HPs, and AD through an online panel survey in July 2018. HPs were selected as 23 kinds of products with associated risks that are management targets of the Ministry of Environment. The international study of asthma and allergies in childhood was used for the AD questionnaires. Logistic regression analysis was used to identify AD affected by the use of HPs. Average number of used HPs was 13.44 out of 23, and average usage frequency of HPs was 3.52 times a month at home in Seoul for the last 1 year. Compared with subjects with a low number of HPs used (reference), subjects with a high number of used HPs (4th quartile) were more likely to have lifetime diagnosis of AD (odds ratio (OR) = 1.77, 95% confidence interval (CI); 1.23-2.54), symptoms of AD in the last 12 months (OR = 2.66, 95% CI; 1.92-3.70), and treatment of AD in the last 12 months (OR = 2.37, 95% CI; 1.48-3.80). Compared with subjects with a low HPs usage frequency (reference), subjects with a high HPs usage frequency (4th quartile) were more likely to have lifetime diagnosis of AD (OR = 1.88, 95% CI; 1.31-2.70), symptoms of AD in the last 12 months (OR = 2.14, 95% CI; 1.54-2.96), and treatment of AD in the last 12 months (OR = 2.23, 95% CI; 1.39-3.60). Therefore, the use of HPs was significantly associated with AD. The findings of this study might be useful as basic data for managing allergic diseases and establishing preventive measures.

The host investigation and virus isolation of hantavirus in Tiantai County / 预防医学

Objective@# To learn the population,virus status and viral types of hantavirus（HV）hosts in Tiantai County of Zhejiang Province from 2011 to 2018,and to provide evidence for hemorrhagic fever with renal syndrome（HFRS）control. @*Methods@# Rodents in Tiantai County were captured by night trapping method. After the species and age of rodents were identified,the composition of rodent species,dominant species and density of rodents were analyzed. The lungs and blood of rodents were sampled to detect the antigen and antibody of HV by immunofluorescence method. The HV antigen-positive lung samples were detected by RT-PCR with specific primers of HV S fragment,then HV was isolated and identified by inoculating Vero-E6 cells.@*Results@# The average rodent density in Tiantai County from 2011 to 2018 was 4.44%. The rodent density in the field and residential areas were 4.94% and 2.23%,respectively. Ten species of rodents were identified,with Apodemus agrarius dominant in the field and Rattus norvegicus in the residential areas. Sixty-seven lung samples were HV antigen positive（4.13%）,one from Rattus norvegicus and the other sixty-six from Apodemus agrarius. Seventy-nine blood samples were HV antibody positive（4.86%）,all from Apodemus agrarius. Thirty-four HV antigen-positive lung samples were positive（50.75%）after RT-PCR amplification. Twenty-two strains of virus were isolated and all of them were from Apodemus agrarius,including twenty-one strains of Hantaan type（HTN）and one strain of Seoul type（SEO）.@*Conclusion @#In Tiantai County,Apodemus agrarius is the main source of HFRS infection;the main epidemic type of HV is HTN and SEO is first found in Apodemus agrarius.

Factors Contributing to Missed Visits for Medical Care among Human Immunodeficiency Virus-Infected Adults in Seoul, Korea

BACKGROUND: It is important that patients with human immunodeficiency virus (HIV) remain under medical care to improve their health and to reduce the potential for HIV transmission. We explored factors associated with missed visits for HIV medical care according to age group. METHODS: Data were derived from a city-wide, cross-sectional survey of 812 HIV-infected adults in Seoul. Multiple logistic analyses were used to explore predictors of missed visits. RESULTS: Of the 775 subjects, 99.3% were treated with antiretroviral therapy (ART) and 12.5% had missed a scheduled appointment for HIV medical care during the past 12 months. Compared with the group aged ≥ 50 years, the 20–34-years and 35–49-years groups were strongly associated with missed visits (adjusted odds ratio [aOR], 5.0 and 2.2, respectively). When divided by age group, lower education level (aOR, 3.0) in subjects aged 20–34 years, low income (aOR, 3.5), National Medical Aid beneficiary (aOR, 0.3), and treatment interruption due to side effects of ART (aOR, 3.4) in subjects aged 35–49 years, and National Medical Aid beneficiary (aOR, 7.1) in subjects aged ≥ 50 years were associated with missed visits. CONCLUSION: In conclusion, younger age was a strong predictor of missed visits for HIV medical care. However, the risk factors differed according to age group, and the strongest predictor in each age group was related to socioeconomic status.

An Outbreak of Scombroid Fish Poisoning Associated with Consumption of Yellowtail Fish in Seoul, Korea

BACKGROUND: In November 2016, an outbreak of scombroid fish poisoning occurred among elementary school students in Seoul, Korea. An epidemiological investigation was conducted to identify the cause and source of the illness. METHODS: A case-control study was conducted among school members who had eaten lunch in the school. The histamine level in the suspect food item (yellowtail steak) was measured. RESULTS: Fifty-five (5.4%) of 1,017 school members who consumed fish for lunch fell ill. The principal symptoms were flushing (100%) and headache (72.7%); the median incubation period was 40 minutes. All had consumed yellowtail steak (odds ratio, 9.24; 95% confidence interval, 1.22–69.91). Leftover steak had an elevated histamine level (293 mg/kg), higher than the allowed 200 mg/kg. CONCLUSION: An outbreak of scombroid fish poisoning was confirmed; this is the first such report in Korea. Detailed food safety guidelines must be established.

Implementing Expanded Rapid Human Immunodeficiency Virus Testing in Public Health Centers in Seoul, 2015 / 감염과화학요법

In 2015, rapid human immunodeficiency virus (HIV) testing was implemented in all 25 public health centers in Seoul. During March and December 2015, 20,987 rapid HIV tests were performed, of which 116 (0.5%) were positive. Compared to those of the period before application of the rapid HIV test in place of conventional enzyme immunoassay method, the number of HIV tests performed and the number of positive results increased by sevenfold and twofold, respectively. In conclusion, expansion of the provision of rapid HIV tests in public health centers increased the number of voluntary HIV tests.

Implementing Expanded Rapid Human Immunodeficiency Virus Testing in Public Health Centers in Seoul, 2015 / 감염과화학요법

In 2015, rapid human immunodeficiency virus (HIV) testing was implemented in all 25 public health centers in Seoul. During March and December 2015, 20,987 rapid HIV tests were performed, of which 116 (0.5%) were positive. Compared to those of the period before application of the rapid HIV test in place of conventional enzyme immunoassay method, the number of HIV tests performed and the number of positive results increased by sevenfold and twofold, respectively. In conclusion, expansion of the provision of rapid HIV tests in public health centers increased the number of voluntary HIV tests.

The Seoul Healthy First Step Project: Introduction and Expansion, Program Content and Performance, and Future Challenges

With the motto ‘Equity from the Start for a Healthy Future’, the Seoul Healthy First Step Project (SHFSP) was launched in 2013 in an attempt to support women with young children, to improve the health and development of babies, and eventually to close the gap in child development. The SHFSP contains both universal components (universal risk assessment of mothers and universal home visitation after birth) and selective components (prenatal and postnatal sustained home visits, mothers' groups, and community service linkage), thereby taking a proportionate universality approach. For sustained home visits, the SHFSP introduced the Maternal and Early Childhood Sustained Home-visiting (MECSH) program from Australia, which has been proven to be effective in improving maternal and childhood outcomes. Between 2013~2017, the SHFSP has paid 58,327 visits to roughly 38 thousand families with babies. In 2017, the SHFSP covered 19.6% of families with newborn babies in Seoul. The SHFSP conducted internal satisfaction surveys of universal and sustained visitation service recipients, in which an overwhelming majority of mothers provided positive feedback. A performance assessment conducted in 2016 by an external organization showed that 93% of SHFSP service recipients were satisfied with the home visitations. Considering the popular support for the program from mothers and families in Seoul (the most affluent area in Korea) and the lack of a national home visiting program to promote early childhood health and development, this program should be expanded nationally in the near future.

The study to estimate the floating population in Seoul, Korea

Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

The presence of sharp-edged weapon related cut mark in Joseon skull discovered at the 16th century market district of Old Seoul City ruins in South Korea / 대한해부학회지

A human skull was discovered at the 16th-century drainage channel of market district ruins, one of the busiest streets in the capital of Joseon kingdom. By anthropological examination, we noticed the cut mark at the right occipital part of the cranium. Judging from the wound property, it might have been caused by a strong strike using a sharp-edged weapon. As no periosteal reaction or healing signs were observed at the cut mark, he might have died shortly after the skull wound was made. We speculated that this might have been of a civilian or soldier victim who died in a battle or the decapitated head of prisoner. This is the first report about the discovery of the skull damaged by sharp-edged weapon at the archaeological sites in the capital city of Joseon Kingdom.

Accuracy of Korean-Mini-Mental Status Examination Based on Seoul Neuro-Psychological Screening Battery II Results / 가정의학회지

BACKGROUND: The Korean-Mini-Mental Status Examination (K-MMSE) is a dementia-screening test that can be easily applied in both community and clinical settings. However, in 20% to 30% of cases, the K-MMSE produces a false negative response. This suggests that it is necessary to evaluate the accuracy of K-MMSE as a screening test for dementia, which can be achieved through comparison of K-MMSE and Seoul Neuropsychological Screening Battery (SNSB)-II results. METHODS: The study included 713 subjects (male 534, female 179; mean age, 69.3±6.9 years). All subjects were assessed using K-MMSE and SNSB-II tests, the results of which were divided into normal and abnormal in 15 percentile standards. RESULTS: The sensitivity of the K-MMSE was 48.7%, with a specificity of 89.9%. The incidence of false positive and negative results totaled 10.1% and 51.2%, respectively. In addition, the positive predictive value of the K-MMSE was 87.1%, while the negative predictive value was 55.6%. The false-negative group showed cognitive impairments in regions of memory and executive function. Subsequently, in the false-positive group, subjects demonstrated reduced performance in memory recall, time orientation, attention, and calculation of K-MMSE items. CONCLUSION: The results obtained in the study suggest that cognitive function might still be impaired even if an individual obtained a normal score on the K-MMSE. If the K-MMSE is combined with tests of memory or executive function, the accuracy of dementia diagnosis could be greatly improved.

Patients Presenting with Advanced Human Immunodeficiency Virus Disease: Epidemiological Features by Age Group

We explored factors influencing presentation with advanced human immunodeficiency virus (HIV) disease by age group. Data were derived from a city-wide cross-sectional survey of 759 HIV-infected adults living in Seoul, Korea. The significance of each observed factor was assessed via multivariate logistic regression. Of subjects aged 20-34 years, lower educational level had a positive influence on presentation with advanced HIV disease (adjusted odds ratio [aOR], 2.43; 95% confidence interval [CI], 1.36-4.34); those recently diagnosed with HIV were more likely to be presented with advanced HIV disease (aOR, 3.17; 95% CI, 0.99-10.2). Of the subjects aged 35-49 years, those w ith advanced HIV disease were more likely to have been diagnosed during health check-ups (aOR, 2.91; 95% CI, 1.15-7.32) or via clinical manifestations (aOR, 3.61; 95% CI, 1.39-9.36). Of the subjects aged > or = 50 years, presentation with advanced HIV disease was significantly more common in older subjects (aOR per increment of 5 years, 2.06; 95% CI, 1.32-3.23) and less common among individuals diagnosed with HIV in 2000-2006 (aOR, 0.18; 95% CI, 0.04-0.83). In conclusion, a lower educational level in younger subjects and more advanced age in older subjects positively influence the presentation of advanced HIV disease.

Patients Presenting with Advanced Human Immunodeficiency Virus Disease: Epidemiological Features by Age Group

We explored factors influencing presentation with advanced human immunodeficiency virus (HIV) disease by age group. Data were derived from a city-wide cross-sectional survey of 759 HIV-infected adults living in Seoul, Korea. The significance of each observed factor was assessed via multivariate logistic regression. Of subjects aged 20-34 years, lower educational level had a positive influence on presentation with advanced HIV disease (adjusted odds ratio [aOR], 2.43; 95% confidence interval [CI], 1.36-4.34); those recently diagnosed with HIV were more likely to be presented with advanced HIV disease (aOR, 3.17; 95% CI, 0.99-10.2). Of the subjects aged 35-49 years, those w ith advanced HIV disease were more likely to have been diagnosed during health check-ups (aOR, 2.91; 95% CI, 1.15-7.32) or via clinical manifestations (aOR, 3.61; 95% CI, 1.39-9.36). Of the subjects aged > or = 50 years, presentation with advanced HIV disease was significantly more common in older subjects (aOR per increment of 5 years, 2.06; 95% CI, 1.32-3.23) and less common among individuals diagnosed with HIV in 2000-2006 (aOR, 0.18; 95% CI, 0.04-0.83). In conclusion, a lower educational level in younger subjects and more advanced age in older subjects positively influence the presentation of advanced HIV disease.

Implementing the Use of Rapid HIV Tests in Public Health Centers in Seoul: Results of a Pilot Project, 2014

To determine whether rapid HIV tests in public health centers might encourage voluntary HIV testing, a pilot project was conducted in four selected public health centers in Seoul, 2014. During the period April 10 to November 28 of pilot project, 3,356 rapid tests were performed, and 38 were confirmed as positive. The monthly average numbers of voluntary HIV tests and HIV-positive cases were up to nine-fold and six-fold larger, respectively, than those of the period before application of the rapid HIV test. Among 2,051 examinees that completed questionnaires, 90.3% were satisfied. In conclusion, the use of rapid HIV tests in public health centers promoted voluntary HIV testing and was satisfactory for examinees.