Correction: Relative bradycardia in patients with COVID‑19

Objective@#and methods To investigate the correlation between temperature and heart rate, we retrospectively reviewed 249 febrile patients with documented COVID-19 patients. RB was defined as a rise in the heart rate from a basal heart rate of less than 10 beats/minute/°C rise in temperature. @*Results@#In this study, the prevalence of RB in patients with COVID-19 was 60.6%. When the HR at peak temperatures for patients with COVID-19 was compared with reference valve (general temperature–heart rate response in infectious disease), our findings demonstrate a relatively lower heart rate at all peak temperatures recorded. Despite differences in heart rate response, there were not significant differences in clinical outcomes (pulmonary manifestation, intensive care unit admission, death). @*Conclusion@#Most patients with COVID-19 are associated with relative bradycardia, not related to clinical outcomes. RB in COVID-19 can be considered as the clinical features for differential diagnosis from other febrile conditions.

Interpretation of the Basic and Effective Reproduction Number / 예방의학회지

In epidemiology, the basic reproduction number (R0) is a term that describes the expected number of infections generated by 1 case in a susceptible population. At the beginning of the coronavirus disease 2019 (COVID-19) pandemic, R0 was frequently referenced by the public health community and the wider public. However, this metric is often misused or misinterpreted. Moreover, the complexity of the process of estimating R0 has caused difficulties for a substantial number of researchers. In this article, in order to increase the accessibility of this concept, we address several misconceptions related to the threshold characteristics of R0 and the effective reproduction number (Rt). Moreover, the appropriate interpretation of the metrics is discussed. R0 should be considered as a population-averaged value that pools the contact structure according to a stochastic transmission process. Furthermore, it is necessary to understand the unavoidable time lag for Rt due to the incubation period of the disease.

An interim review of the epidemiological characteristics of 2019 novel coronavirus / 한국역학회지

OBJECTIVES@#The 2019 novel coronavirus (2019-nCoV) from Wuhan, China is currently recognized as a public health emergency of global concern. @*METHODS@#We reviewed the currently available literature to provide up-to-date guidance on control measures to be implemented by public health authorities. @*RESULTS@#Some of the epidemiological characteristics of 2019-nCoV have been identified. However, there remain considerable uncertainties, which should be considered when providing guidance to public health authorities on control measures. @*CONCLUSIONS@#Additional studies incorporating more detailed information from confirmed cases would be valuable.

An interim review of the epidemiological characteristics of 2019 novel coronavirus / 한국역학회지

OBJECTIVES@#The 2019 novel coronavirus (2019-nCoV) from Wuhan, China is currently recognized as a public health emergency of global concern. @*METHODS@#We reviewed the currently available literature to provide up-to-date guidance on control measures to be implemented by public health authorities. @*RESULTS@#Some of the epidemiological characteristics of 2019-nCoV have been identified. However, there remain considerable uncertainties, which should be considered when providing guidance to public health authorities on control measures. @*CONCLUSIONS@#Additional studies incorporating more detailed information from confirmed cases would be valuable.

The Delay in Confirming COVID-19 Cases Linked to a Religious Group in Korea / 예방의학회지

Objectives@#As of March 3, 2020, the Shincheonji religious group accounted for the majority of Korean cases of coronavirus disease 2019 (COVID-19). Nonetheless, the most likely cause of the broad spread of COVID-19 among members of the Shincheonji religious group remains largely unknown. @*Methods@#We obtained data of laboratory-confirmed cases related to the Shincheonji religious group from press releases by Korean public health authorities and news reports. We measured the period from the date of illness onset to the date of COVID-19 confirmation. @*Results@#We analysed data from 59 cases (median age, 30 years). The estimated median period between the date of symptom onset and the date of COVID-19 confirmation was 4 days (95% confidence interval, 1-12). @*Conclusions@#There was a delay in COVID-19 confirmation from the date of illness onset among the cases linked to the Shincheonji religious group. This delay likely contributed to the occurrence of many cases of COVID-19 in the group.

Interpretation of the Basic and Effective Reproduction Number / 예방의학회지

In epidemiology, the basic reproduction number (R0) is a term that describes the expected number of infections generated by 1 case in a susceptible population. At the beginning of the coronavirus disease 2019 (COVID-19) pandemic, R0 was frequently referenced by the public health community and the wider public. However, this metric is often misused or misinterpreted. Moreover, the complexity of the process of estimating R0 has caused difficulties for a substantial number of researchers. In this article, in order to increase the accessibility of this concept, we address several misconceptions related to the threshold characteristics of R0 and the effective reproduction number (Rt). Moreover, the appropriate interpretation of the metrics is discussed. R0 should be considered as a population-averaged value that pools the contact structure according to a stochastic transmission process. Furthermore, it is necessary to understand the unavoidable time lag for Rt due to the incubation period of the disease.

Hepatitis A Virus Infection from a Contaminated Tap of Ground Water Facility in a Neighborhood Park, Republic of Korea / 감염과화학요법

A patient with Hepatitis A virus (HAV) infection was notified to the public health authority. The identical HAV was found at a water dispensing outlet at the ground water facility and the toilet close to the facility. Serosurveillance in the community was conducted. Suspicious individuals were asked to visit city public health center and had a serologic test for anti-HAV Ig M. Overall, 100 individuals were tested, and all were negative for the anti-HAV Ig M. In our study cohort, we could not identify additional case of HAV infection.

Norovirus Outbreak in a Kindergarten: Human to Human Transmission among Children / 감염과화학요법

An outbreak of acute gastroenteritis was reported from a kindergarten on January 5, 2018 and investigation was conducted. A case was defined as a kindergartener presented with vomiting or diarrhea twice a day between January 1 and January 5, 2018. All kindergarteners were interviewed to identify the factor associated with case development. Fifteen (31.3%) children of a total of 48 were identified as cases, and four were confirmed to be Group II, Norovirus positive. In our study, based on the pattern of epidemic curve and different attack rate by classroom in a kindergarten, Norovirus was likely transmitted from human to human.

Outbreak investigation of pertussis in an elementary school: a case-control study among vaccinated students

PURPOSE: A pertussis patient from an elementary school, in Gyeonggi Province, Korea, was notified to public health authority on July 25, 2017. Epidemiologic investigation was conducted to identify the magnitude, possible source of infection and risk factors for this outbreak on August 17, 2017. MATERIALS AND METHODS: A case was defined as the school student experiencing cough for more than two weeks with or without paroxysmal, whoop, or post-tussive vomiting. Control was defined as the student polymerase chain reaction-negative at the school. School based surveillance was implemented to identify additional cases. RESULTS: From June 29 to August 27, 2017, nine patients of pertussis were identified from an elementary school. Among nine cases, eight were confirmed by polymerase chain reaction positive. All cases had cough, one (11%) had post-tussive vomiting, and one (11%) had fever. Eight cases had macrolide for 7 days in outpatient clinic, and one case admitted in a hospital. There was no significant difference of demographic factors including gender (p=0.49), age group (p=0.97), number of series of vaccination of pertussis (p=0.52), the number of participation of after school activity (p=0.28), and the time elapsed since last vaccination (p=0.42). However, we found the history of contact within the classroom or after-school activity was only the independent risk factor among all the demographic factors collected (odds ratio, 63.61; 95% confidence interval, 4.35 to 930.79). CONCLUSION: The contributing factor for transmission is associated with the case-contact. Immediate identification of pertussis with use of appropriate diagnostic test may help to avoid a large number of cases.

Investigation of Scarlet Fever Outbreak in a Kindergarten / 감염과화학요법

BACKGROUND: Scarlet fever is caused by a group A streptococcal (GAS) infection. On April 3, 2017, an outbreak among children in a kindergarten was reported to the local health department. An epidemiologic investigation was conducted to identify the possible transmission route of this outbreak and to recommend appropriate control measures. MATERIALS AND METHODS: A retrospective cohort study was conducted using questionnaires including age, sex, the classroom attended at a kindergarten, and date and type of symptoms developed. A case-patient is defined as a child having sore throat, fever, skin rash, or strawberry tongue with or without laboratory confirmation of GAS infection between March 28 and April 28, 2017. RESULTS: The index case-patients developed symptoms on March 28, 2017, and this outbreak persisted over a period of 16 days. The outbreak affected 21 out of 158 children (13.3%) in the kindergarten, with the mean age of 4.2 (range 3–5) years; 12 (57.1%) of them were boys. The common symptoms reported were fever (71.4%), sore throat (71.4%), reddened tonsil (57.1%), and skin rash (52.4%). The epidemiologic analysis showed that children attending one of the classrooms in the kindergarten were 14.12 times affected than the other classrooms (relative risk, 14.12; 95% confidence interval, 4.99–33.93; P 24 hours after starting appropriate antibiotic treatment, and all the children in the kindergarten were instructed to keep strict personal hygiene practices. CONCLUSION: Our results suggest that the outbreak likely affected from the index case-patients who attended to one of the classrooms in the kindergarten. This highlights the importance of immediate notification of outbreak to prevent large number of patients.

Investigation of Scarlet Fever Outbreak in a Kindergarten / 감염과화학요법

BACKGROUND: Scarlet fever is caused by a group A streptococcal (GAS) infection. On April 3, 2017, an outbreak among children in a kindergarten was reported to the local health department. An epidemiologic investigation was conducted to identify the possible transmission route of this outbreak and to recommend appropriate control measures. MATERIALS AND METHODS: A retrospective cohort study was conducted using questionnaires including age, sex, the classroom attended at a kindergarten, and date and type of symptoms developed. A case-patient is defined as a child having sore throat, fever, skin rash, or strawberry tongue with or without laboratory confirmation of GAS infection between March 28 and April 28, 2017. RESULTS: The index case-patients developed symptoms on March 28, 2017, and this outbreak persisted over a period of 16 days. The outbreak affected 21 out of 158 children (13.3%) in the kindergarten, with the mean age of 4.2 (range 3–5) years; 12 (57.1%) of them were boys. The common symptoms reported were fever (71.4%), sore throat (71.4%), reddened tonsil (57.1%), and skin rash (52.4%). The epidemiologic analysis showed that children attending one of the classrooms in the kindergarten were 14.12 times affected than the other classrooms (relative risk, 14.12; 95% confidence interval, 4.99–33.93; P 24 hours after starting appropriate antibiotic treatment, and all the children in the kindergarten were instructed to keep strict personal hygiene practices. CONCLUSION: Our results suggest that the outbreak likely affected from the index case-patients who attended to one of the classrooms in the kindergarten. This highlights the importance of immediate notification of outbreak to prevent large number of patients.

Foodborne Illness Outbreaks in Gyeonggi Province, Korea, Following Seafood Consumption Potentially Caused by Kudoa septempunctata between 2015 and 2016

OBJECTIVES: Investigations into foodborne illness, potentially caused by Kudoa septempunctata, has been ongoing in Korea since 2015. However, epidemiological analysis reporting and positive K septempunctata detection in feces in Korea has been limited. The aim of this study was to provide epidemiologic data analysis of possible food poisoning caused by K septempunctata in Korea. METHODS: This study reviewed 16 Kudoa outbreak investigation reports, including suspected cases between 2015 and 2016 in Gyeonggi province, Korea. Suspected Kudoa foodborne illness outbreak was defined as “evidence of K septempunctata in at least one sample.” The time and place of outbreak, patient symptoms and Kudoa (+) detection rate in feces was analyzed. RESULTS: Kudoa foodborne illness outbreaks occurred in most patients in August (22.6%) and in most outbreaks in April (25%). The attack rate was 53.9% and the average attack rate in patients who had consumed olive flounder was 64.7%. The average incubation period was 4.3 hours per outbreak. Diarrhea was the most common symptom which was reported by 91.5% patients. The Kudoa (+) detection rate in feces was 69.2% of cases. CONCLUSION: Monthly distribution of Kudoa foodborne illness was different from previous studies. The Kudoa (+) detection rate in feces decreased rapidly between 25.5 and 28.5 hours of the time interval from food intake to epidemiologic survey. To identify effective period of time of investigation, we believe additional study with extended number of cases is necessary.

One Health Perspectives on Emerging Public Health Threats / 예방의학회지

Antimicrobial resistance and emerging infectious diseases, including avian influenza, Ebola virus disease, and Zika virus disease have significantly affected humankind in recent years. In the premodern era, no distinction was made between animal and human medicine. However, as medical science developed, the gap between human and animal science grew deeper. Cooperation among human, animal, and environmental sciences to combat emerging public health threats has become an important issue under the One Health Initiative. Herein, we presented the history of One Health, reviewed current public health threats, and suggested opportunities for the field of public health through better understanding of the One Health paradigm.

Community-acquired Legionnaires’ Disease in a Newly Constructed Apartment Building / 예방의학회지

OBJECTIVES: Legionnaires' disease (LD) is a severe type of pneumonia caused by inhalation of aerosols contaminated with Legionella. On September 22, 2016, a single case of LD was reported from a newly built apartment building in Gyeonggi province. This article describes an epidemiologic investigation of LD and identification of the possible source of infection. METHODS: To identify the source of LD, we interviewed the patient's husband using a questionnaire based on the Legionella management guidelines from the Korea Centers for Disease Control and Prevention. Water samples from the site were collected and analyzed. An epidemiological investigation of the residents and visitors in the apartment building was conducted for 14 days before the index patient's symptoms first appeared to 14 days after the implementation of environmental control measures. RESULTS: Legionella pneumophila serogroup 1 was isolated from the heated-water samples from the patient's residence and the basement of the apartment complex. Thirty-two suspected cases were reported from the apartment building during the surveillance period, yet all were confirmed negative based on urinary antigen tests. CONCLUSIONS: The likely source of infection was the building's potable water, particularly heated water. Further study of effective monitoring systems in heated potable water should be considered.