Current Status of Q Fever and the Challenge of Outbreak Preparedness in Korea: One Health Approach to Zoonoses

Human Q fever, a zoonosis caused by Coxiella burnetii, presents with diverse clinical manifestations ranging from mild self-limited febrile illnesses to life-threatening complications such as endocarditis or vascular infection. Although acute Q fever is a benign illness with a low mortality rate, a large-scale outbreak of Q fever in the Netherlands led to concerns about the possibility of blood transfusion-related transmission or obstetric complications in pregnant women. Furthermore, a small minority (< 5%) of patients with asymptomatic or symptomatic infection progress to chronic Q fever. Chronic Q fever is fatal in 5–50% of patients if left untreated. In South Korea, Q fever in humans was designated as a notifiable infectious disease in 2006, and the number of Q fever cases has increased sharply since 2015. Nonetheless, it is still considered a neglected and under-recognized infectious disease. In this review, recent trends of human and animal Q fever in South Korea, and public health concerns regarding Q fever outbreaks are reviewed, and we consider how a One Health approach could be applied as a preventive measure to prepare for zoonotic Q fever outbreaks.

COVID-19 outbreak and risk factors for infection in a taekwondo gym in the Republic of Korea

Objectives@#Relatively few studies have assessed risk factors for coronavirus disease 2019 (COVID-19) in public facilities used by children and adolescents. This study presents an analysis of a COVID-19 outbreak that occurred in a taekwondo gym in Korea, predominantly among children and adolescents, with the aim of providing insights on managing COVID-19 outbreaks in similar facilities. @*Methods@#All 108 taekwondo gym students and staff received COVID-19 tests. A survey and closed-circuit television analyses were used to identify risk factors. A univariate analysis was conducted, followed by multivariate logistic regression analysis with backward elimination for variables with a significance level <0.10 in the univariate analysis. @*Results@#COVID-19 was confirmed in 30 of 108 subjects at the taekwondo gym (attack rate, 27.8%). The outbreak started in an adult class student. This student transmitted the virus to the staff, who consequently transmitted the virus to adolescent students. In the univariate analysis, the relative risk for younger age (≤9 years) was 2.14 (95% confidence interval [CI], 1.01–4.54; p=0.054), and that for food consumption inside the gym was 2.12 (95% CI, 1.04–4.30; p=0.048). In the multivariate logistic regression analysis, the odds ratio for younger age was 2.96 (95% CI, 1.07–8.20; p=0.036), and that for food consumption inside the gym was 3.00 (95% CI, 1.10–8.17; p=0.032). @*Conclusion@#Food consumption inside the facility and young age were significant risk factors for COVID-19 transmission in this taekwondo gym. Food consumption should be prohibited in sports facilities, and infection prevention education for young students is also required.

Seroprevalence and Risk Factors for Severe Fever with Thrombocytopenia Syndrome among the Korea National Park Service Workers / 農村醫學 地域保健

Objectives@#This study was carried out to understand the seroprevalence and risk factors for severe fever with thrombocytopenia syndrome (SFTS) among the Korea National Park Service (KNPS) workers. @*Methods@#We used the stored serum samples (763) and survey results collected from the previous investigation on scrub typhus and Lyme disease among the KNPS workers during 2016-2017. The serum samples were analyzed by double-antigen sandwich enzyme-linked immunosorbent assay, which was used to test the total antibody including IgG and IgM. @*Results@#The SFTS seroprevalence among the KNPS worrkers was 1.4%. In multivariate logistic analysis, the national park exploration programs (odds ratio, 3.48; 95% confidence interval, 1.01-12.01) was significantly associated with the seroprevalence of SFTS. @*Conclusion@#This study was the first serological study of SFTS among forestry workers in South Korea. Although the KNPS workers are at a high-risk group of SFTS, the prevention activities related to the working environment and habit was insufficient. Thus, systematic prevention education and training for the KNPS workers need to be strengthened.

COVID-19 Outbreak and Presymptomatic Transmission in Pilgrim Travelers Who Returned to Korea from Israel

Background@#On February 21, 2020, 2 coronavirus disease 2019 (COVID-19) cases in pilgrim travelers from Korea to Israel were identified. We investigated the source of infection, clinical features of COVID-19, and transmission potential of presymptomatic and asymptomatic cases. @*Methods@#All 39 pilgrim travelers were aggressively tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Their clinical features and possible source of infection were investigated by interview and review of their medical records. Ten confirmed cases without symptoms at the first sampling dates were selected for follow-up reverse transcription polymerase chain reaction tests. @*Results@#Of the 39 pilgrim travelers, 30 (77%) were positive for SARS-CoV-2. Among the 30 positive COVID-19 cases, 4 (13%) were asymptomatic. Available follow-up cycle threshold values from 10 cases gradually increased over time and were lower during the presymptomatic period than during the postsymptomatic period. Out of 328 contacts related to the COVID-19 cases in the pilgrim travelers, 22 additional cases (7%) were confirmed with SARS-CoV-2 infections. Three tertiary cases were identified to be transmitted by presymptomatic secondary cases. @*Conclusion@#To prevent transmission of COVID-19, we need to focus on presymptomatic and asymptomatic cases, and massive testing for SARS-CoV-2 is required. More research about the possibility of presymptomatic transmission over 2 days before symptom onset is required.

COVID-19 Outbreak and Presymptomatic Transmission in Pilgrim Travelers Who Returned to Korea from Israel

Background@#On February 21, 2020, 2 coronavirus disease 2019 (COVID-19) cases in pilgrim travelers from Korea to Israel were identified. We investigated the source of infection, clinical features of COVID-19, and transmission potential of presymptomatic and asymptomatic cases. @*Methods@#All 39 pilgrim travelers were aggressively tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Their clinical features and possible source of infection were investigated by interview and review of their medical records. Ten confirmed cases without symptoms at the first sampling dates were selected for follow-up reverse transcription polymerase chain reaction tests. @*Results@#Of the 39 pilgrim travelers, 30 (77%) were positive for SARS-CoV-2. Among the 30 positive COVID-19 cases, 4 (13%) were asymptomatic. Available follow-up cycle threshold values from 10 cases gradually increased over time and were lower during the presymptomatic period than during the postsymptomatic period. Out of 328 contacts related to the COVID-19 cases in the pilgrim travelers, 22 additional cases (7%) were confirmed with SARS-CoV-2 infections. Three tertiary cases were identified to be transmitted by presymptomatic secondary cases. @*Conclusion@#To prevent transmission of COVID-19, we need to focus on presymptomatic and asymptomatic cases, and massive testing for SARS-CoV-2 is required. More research about the possibility of presymptomatic transmission over 2 days before symptom onset is required.

COVID-19 in Nursing Facilities: Experience in Republic of Korea

ObjectivesCoronavirus disease 2019 (COVID-19) outbreaks in nursing facilities can easily lead to a high rate of infection and fatality. A surge in newly infected cases in the first quarter of 2020 in Gyeongsan-si, in the Republic of Korea, was followed by several outbreaks in nursing facilities in the same area. The aim of this study is to report on the epidemiological investigation and the management to reduce the infection rate in nursing facilities for older adults.MethodsThe municipal government and the Korea Centers for Disease Control and Prevention performed an epidemiological investigation into 5 nursing facilities that reported a high number of COVID-19 infection cases from February to May 2020. COVID-19 infected cases in the facilities were investigated to identify the infection routes, and the fatality rate of the 5 facilities.ResultsThe 5 facilities had a combined fatality rate of 12.2% (9 deceased among the 74 infected cases). The median age of the deceased was 87 years old (range: 82–91). The infection was first identified on February 27th, 2020, peaked on March 6th, and was last detected on March 24th, 2020.ConclusionDifficulties specific to such facilities included the delay in the recognition of symptoms and limitation in distancing. Tailored strategies such as daily monitoring of symptoms and proactive COVID-19 screening of quarantined residents, contributed to a decline in the infections in the facilities.

Factors related to COVID-19 Incidence and Mortality rate in Gyeongsangbuk-do, Korea / 農村醫學 地域保健

Objectives@#Gyeongsangbuk-do has entered a super-aged society with 20.7% of the population aged 65 and older. As of April 30, 2020, the death rate of COVID-19(3.8 people) in Gyeongsangbuk-do is higher than the national mortality rate (2.3 people), and the fatality rate of COVID-19 by age accounts for more than half of the total of 58.6%, so it is time to propose to prevent infectious diseases in the event of additional infectious disease disasters COVID-19. @*Methods@#We collected daily data on the number of confirmed cases and deaths due to COVID-19 from 19 February to 30 April 2020. The data collected was evaluated using the SPSS 21.0 statistical package. @*Results@#As a result of comparing the incidence and death-related factors of confirmed patients in Gyeongsangbuk-do, there were significant differences in age group (p<0.001), underlying disease (p<0.001), and residence type (p<0.033). @*Conclusion@#Factors affecting the mortality rate of confirmed patients in Gyeongsangbuk-do have been combined with individual level factors(age, gender, underlying disease), which means individual characteristics that have existed since before the disease, and regional level factors(Type of Residence), which are external factors that enable the use of medical resources. Therefore, each local government is required to establish preventive measures considering individual and regional level factors.

Seroprevalence and risk factors of Lyme disease among Korean deer farmers / 農村醫學 地域保健

No abstract available.

A Study on the Febrile Illness in Autumn among Farmers in Gyeongju-si: Scrub typhus, Leptospirosis, HFRS / 農村醫學 地域保健

OBJECTIVES: This study aimed to assess the status of Scrub typhus, Leptospirosis and HFRS(hemorrhagic fever with renal syndrome) among farmers with febrile illness. METHODS: We involved a total of 841 farmers who had febrile illness(508 and 333 village residents were, respectively, three and four district of Gyeongju city) selected during autumn of 2014 and 2015. Data were collected by survey questionnaires and blood sample examination. RESULTS: Serum response rate for Scrub typhus and Leptospirosis was 1.5% each and 1.9% for HFRS. Serum response rate for Scrub typhus was significantly higher for tick-bite cases(38.5%), while Leptospirosis was significantly higher for those who were in fruit–planting work(23.1%). Similarly, serum response rate was significantly higher for HFRS who were working in venyl green house work(25.0%). CONCLUSIONS: Government authority should develop effective and efficient preventive strategies to create awareness of infectious diseases among farmers. Extending information, education and communication be reached to farmers that could change their perception and help early diagnosis and treatment and reduce the disease burden and its complication.

Serologic Survey and Risk Factors for Coxiella burnetii Infection among Dairy Cattle Farmers in Korea

BACKGROUND: The zoonotic disease Q fever is caused by Coxiella burnetii and usually affects high-risk human populations. We conducted a serological survey of dairy cattle farmers in Korea to determine seroreactivity and identify risk factors for C. burnetii infection. METHODS: This cross-sectional study included 1,824 of 7,219 dairy cattle farms (25.3%) in the study region. The selected dairy cattle farmers visited the nearest public health centers or branches with completed questionnaires. Serum samples from the farmers were tested using an indirect immunofluorescence assay to detect phase II C. burnetii immunoglobulin (Ig) G or M antibodies. RESULTS: A total of 1,222 dairy cattle farmers from 784 dairy cattle farms (43.0%) participated in this study, and 11.0% (134/1,222) exhibited seroreactivity, defined as a phase II antigen IgG or IgM titer ≥ 1:16. In the multivariate analysis, male sex, residence in Gyeonggi Province, a larger herd size, and ocular/oral contact with birth products during calf delivery were significantly associated with a higher risk of C. burnetii infection. Furthermore, the risk was significantly lower among farmers who always wore protective gloves while cleaning cattle excretion, compared to those who sometimes or rarely wore protective gloves. CONCLUSION: Dairy cattle farmers should exercise caution by avoiding ocular/oral contact with birth products during calf delivery and by using protective equipment (including gloves).

Analysis of Kudoa septempunctata as a cause of foodborne illness and its associated differential diagnosis / 한국역학회지

No abstract available.

The direction of restructuring of a Korea field epidemiology training program through questionnaire survey among communicable disease response staff in Korea / 한국역학회지

We used a survey about the need for an educational training of infectious disease response staff in Korea Centers for Disease Control and Prevention (KCDC) and officer in metropolitan cities and provincial government to conduct field epidemiological investigation. The survey was conducted from January 25 to March 15, 2016. A total of 173 participants were selected from four different groups as follows: 27 clinical specialists, 22 Epidemic Intelligence Service (EIS) officers, 82 KCDC staff, and 42 local health department officials. Results revealed that 83% of KCDC staff and 95% of local health department officials agreed on the need for educational training to strengthen capability of personnel to conduct epidemic research and investigation. The level of their need for training was relatively high, while self-confidence levels of individuals to conduct epidemic research and investigation was low. It was concluded that there was a need to develop training programs to enhance the ability of public health officials, EIS officers, KCDC staff, and local health department personnel to conduct epidemic research and investigation.

The direction of restructuring of a Korea field epidemiology training program through questionnaire survey among communicable disease response staff in Korea / 한국역학회지

We used a survey about the need for an educational training of infectious disease response staff in Korea Centers for Disease Control and Prevention (KCDC) and officer in metropolitan cities and provincial government to conduct field epidemiological investigation. The survey was conducted from January 25 to March 15, 2016. A total of 173 participants were selected from four different groups as follows: 27 clinical specialists, 22 Epidemic Intelligence Service (EIS) officers, 82 KCDC staff, and 42 local health department officials. Results revealed that 83% of KCDC staff and 95% of local health department officials agreed on the need for educational training to strengthen capability of personnel to conduct epidemic research and investigation. The level of their need for training was relatively high, while self-confidence levels of individuals to conduct epidemic research and investigation was low. It was concluded that there was a need to develop training programs to enhance the ability of public health officials, EIS officers, KCDC staff, and local health department personnel to conduct epidemic research and investigation.

Analysis of Kudoa septempunctata as a cause of foodborne illness and its associated differential diagnosis / 한국역학회지

No abstract available.

Necessity of a Surveillance System for Tick-borne Encephalitis

No abstract available.

Epidemiological Investigation on an Outbreak of Norovirus Infection at a High School in Gyeongju City, 2009 / 農村醫學 地域保健

OBJECTIVES: An outbreak of norovirus occurred at a high school in Gyeongju city in 2009. An epidemiological investigation was carried out to examine the infection source and the transmission route of norovirus, and to prevent a recurrence. METHODS: A questionnaire survey was conducted for 520 male students and 8 food handlers. Rectal swabs were examined in 21 symptomatic students and the 8 food handlers by Gyeongsangbukdo Government Public Institute of Health & Environment, and an environmental investigation was performed. A case-control study was used to evaluate the association between risk factors and disease. RESULTS: The attack rate was 21.3% (111/520) between January 29 and February 10, and norovirus GII was isolated from 12 of 21 students. Food handlers had no symptoms and their stool samples were negative. The case-control study revealed that seasoned soy bean sprouts {odds ratio (OR): 2.542, 95% CI=1.315-4.915} and drinking water from the purifiers in the cafeteria (OR: 2.854, 95% CI=1.107-7.358) supplied on February 3 were significant risk factors for the outbreak. Water pipes and waste pipes were located in the same place where was filled with some water and trace of high water level was detected. CONCLUSIONS: The major risk factors for this norovirus outbreak were presumed to be the contaminated seasoned soy bean sprouts and drinking water from the purifiers in the cafeteria. More strict personal and environmental hygiene need to be enforced to prevent such outbreaks.

Work-Related Musculoskeletal Symptoms Among Dairy Farmers in Gyeonggi Province, Korea / 예방의학회지

OBJECTIVES: The prevalence of work-related musculoskeletal symptoms (WMS) among Korean dairy farmers has not been investigated. The purpose of this study was to assess the prevalence of WMS and to evaluate the relationship between WMS and risk factors. METHODS: Self-developed questionnaires including the questionnaire developed by the Korean Occupational Safety and Health agency (KOSHA) were used to investigate WMS among dairy farmers in Gyeonggi Province, Korea. We informed selected dairy farmers about the study and sent the questionnaires by registered mail. They visited a public health center nearby or a branch of public health center on the appointed date and skillful researchers identified or conducted the questionnaires by interview. We analyzed 598 (32.8%) of the 1824 dairy farmers. Multiple logistic regression was implemented to estimate the odds ratios of risk factors. RESULTS: The mean age of the respondents was 50.4 +/- 8.7 years and the proportion of males was 63.0%. The prevalence of WMS at any site was 33.3%. The prevalence of neck WMS was 2.2%, shoulders 10.0%, arms/elbows 5.0%, hands/wrists/fingers 4.2%, low back 11.5%, and legs/feet 11.7%. The adjusted odds ratio of low back WMS for milking 4 or more hours per day was 4.231 (95% CI = 1.124 - 15.932) and statistically significant. Low back WMS (2.827, 95% CI = 1.545 - 5.174) was significantly decreased by education. CONCLUSIONS: Low back WMS increased with milking hours and milking 4 or more hours per day was significantly associated with low back WMS. Low back WMS was significantly reduced with education. We hope that there will be increased attention about WMS in dairy farmers and the subject of future investigations.

Hygienic State and Awareness of Drink Vending Machines in a City / 農村醫學 地域保健

OBJECTIVE: This study was conducted to investigate the hygienic state and awareness of drink vending machines in a city. METHODS: Twelve of the most frequently used vending machines in various areas were selected in October 2008. As soon as fresh samples of milk coffee and adlay tea were collected in sterile containers from each machine, the temperature was measured. The samples were carried on ice to the laboratory to test total plate counts and Escherichia coli contamination. College students were inquired about drink vending machine hygiene by implementing self-developed questionnaires. RESULTS: The temperature of 6 milk coffee samples (50.0%) and 8 adlay tea samples (66.7%) turned out to be inadequate. The total plate counts of milk coffee samples were all adequate, although 9 adlay tea samples (75.0%) were inadequate. All the beverage samples were negative for E. coli. In questionnaires obtained from 74 users of coffee vending machines, only 2 (2.7%) expected the hygienic state of vending machines to be good. There were 27 people (33.3%) that knew the existence of hygiene-related laws for vending machines. CONCLUSIONS: This study reveals that the hygienic state of drink vending machines insufficiently reaches the standard for the hot beverage and that most people are not aware of importance of vending machine hygiene. It is necessary to make improvement in the hygiene of vending machines and public awareness in this city.