Pathogenicity of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Cats in Mice and Ferrets, South Korea, 2023.

The prevalence of highly pathogenic avian influenza (HPAI) A(H5N1) viruses has increased in wild birds and poultry worldwide, and concomitant outbreaks in mammals have occurred. During 2023, outbreaks of HPAI H5N1 virus infections were reported in cats in South Korea. The H5N1 clade 2.3.4.4b viruses isolated from 2 cats harbored mutations in the polymerase basic protein 2 gene encoding single amino acid substitutions E627K or D701N, which are associated with virus adaptation in mammals. Hence, we analyzed the pathogenicity and transmission of the cat-derived H5N1 viruses in other mammals. Both isolates caused fatal infections in mice and ferrets. We observed contact infections between ferrets, confirming the viruses had high pathogenicity and transmission in mammals. Most HPAI H5N1 virus infections in humans have occurred through direct contact with poultry or a contaminated environment. Therefore, One Health surveillance of mammals, wild birds, and poultry is needed to prevent potential zoonotic threats.

Time from Exposure to Diagnosis among Quarantined Close Contacts of SARS-CoV-2 Omicron Variant Index Case-Patients, South Korea.

To determine optimal quarantine duration, we evaluated time from exposure to diagnosis for 107 close contacts of severe acute respiratory syndrome coronavirus 2 Omicron variant case-patients. Average time from exposure to diagnosis was 3.7 days; 70% of diagnoses were made on day 5 and 99.1% by day 10, suggesting 10-day quarantine.

Community Transmission of SARS-CoV-2 Omicron Variant, South Korea, 2021.

In South Korea, a November 2021 outbreak caused by severe acute respiratory syndrome coronavirus 2 Omicron variant originated from 1 person with an imported case and spread to households, kindergartens, workplaces, restaurants, and hospitals, resulting in 11 clusters within 3 weeks. An epidemiologic curve indicated rapid community transmission of the Omicron variant.

The relationship between metabolic syndrome and the incidence of colorectal cancer.

OBJECTIVES: This study evaluated the incidence of colorectal cancer (CRC) according to the number of metabolic syndrome (MetS) components. METHODS: Using health checkup and insurance claims data of 6,365,409 subjects, the occurrence of CRC according to stage of MetS by sex was determined from the date of the health checkup in 2009 until December 31, 2018. RESULTS: Cumulative incidence rates (CIR) of CRC in men and women was 3.9 and 2.8 per 1000 (p < 0.001), respectively. CIR of CRC for the normal, pre-MetS, and MetS groups in men was 2.6, 3.9, and 5.5 per 1000 (p < 0.001) and CIR in women was 2.1, 2.9, and 4.5 per 1000 (p < 0.001), respectively. Compared with the normal group, the hazard ratio (HR) of CRC for the pre-MetS group was 1.25 (95% CI 1.17-1.33) in men and 1.09 (95% CI 1.02-1.17) in women, and the HR of CRC for the MetS group was 1.54 (95% CI 1.43-1.65) in men and 1.39 (95% CI 1.26-1.53) in women after adjustment. CONCLUSIONS: We found that MetS is a risk factor for CRC in this study. Therefore, the prevention and active management of MetS would contribute to the prevention of CRC.

Medical visits, antihypertensive prescriptions and medication adherence among newly diagnosed hypertensive patients in Korea.

OBJECTIVES: The objective of this study was to assess the antihypertensive medication adherence in patients who were newly diagnosed with hypertension in Korea. METHODS: Study subjects were diagnosed with hypertension for the first time by the General Health Screening in 2012 and were 65,919. As indices, visiting rate to medical institution, the antihypertensive prescription rate, medication possession ratio and the rate of appropriate medication adherence were used. The qualification data, the General Health Screening data and the health insurance claims data were used. RESUTLS: Visiting rate to medical institution within one-year was 42.3%. Gender, age, family history of hypertension, smoking status, drinking frequency, insurance type, BMI, hypertension status, blood glucose level and LDL-cholesterol level were significant variables for visiting a medical institution. Of the study subjects who visited a medical institution, the antihypertensive prescription rate was 89.1%. Medication possession ratio was 70.9% and the rate of appropriate medication adherence was 60.6%. Age, family history of hypertension, smoking status, BMI level, hypertension level, blood glucose level, status, and LDL-cholesterol level were significant variables for the antihypertensive prescription and gender, age, family history of hypertension, smoking status, BMI, hypertension status, and the time of the first visit to a medical institution were significant variables for appropriate medication adherence. CONCLUSIONS: This study showed that the antihypertensive medication adherence in patients who were newly diagnosed with hypertension was not relatively high in Korea. National Health Insurance Service should support an environment in which medical institutions and those diagnosed with hypertension can fulfill their roles.

Retrospective observation on contribution and limitations of screening for breast cancer with mammography in Korea: detection rate of breast cancer and incidence rate of interval cancer of the breast.

BACKGROUND: The purpose of this study was to determine the benefits and limitations of screening for breast cancer using mammography. METHODS: Descriptive design with follow-up was used in the study. Data from breast cancer screening and health insurance claim data were used. The study population consisted of all participants in breast cancer screening from 2009 to 2014. Crude detection rate, positive predictive value and sensitivity and specificity of breast cancer screening and, incidence rate of interval cancer of the breast were calculated. RESULTS: The crude detection rate of breast cancer screening per 100,000 participants increased from 126.3 in 2009 to 182.1 in 2014. The positive predictive value of breast cancer screening per 100,000 positives increased from 741.2 in 2009 to 1,367.9 in 2014. The incidence rate of interval cancer of the breast per 100,000 negatives increased from 51.7 in 2009 to 76.3 in 2014. The sensitivities of screening for breast cancer were 74.6% in 2009 and 75.1% in 2014 and the specificities were 83.1% in 2009 and 85.7% in 2014. CONCLUSIONS: To increase the detection rate of breast cancer by breast cancer screening using mammography, the participation rate should be higher and an environment where accurate mammography and reading can be performed and reinforcement of quality control are required. To reduce the incidence rate of interval cancer of the breast, it will be necessary to educate women after their 20s to perform self-examination of the breast once a month regardless of participation in screening for breast cancer.

Epidemiological characteristics of carbapenemase-producing Enterobacteriaceae outbreaks in the Republic of Korea between 2017 and 2022.

BACKGROUND: We aimed to describe the epidemiological characteristics of carbapenemase-producing Enterobacteriaceae (CPE) outbreaks in healthcare settings in the Republic of Korea between 2017 and 2022. METHODS: Under the national notifiable disease surveillance system, we obtained annual descriptive statistics regarding the isolated species, carbapenemase genotype, healthcare facility type, outbreak location and duration, and number of patients affected and recommended interventions. We used epidemiological investigation reports on CPE outbreaks reported to Korea Disease Control and Prevention Agency from June 2017 to September 2022. RESULTS: Among the 168 reports analyzed, Klebsiella pneumoniae (85.1%) was the most frequently reported species, while K. pneumoniae carbapenemase (KPC, 82.7%) was the most common carbapenemase genotype. Both categories increased from 2017 to 2022 (p<0.01). General hospitals had the highest proportion (54.8%), while tertiary general hospitals demonstrated a decreasing trend (p<0.01). The largest proportion of outbreaks occurred exclusively in intensive care units (ICUs, 44.0%), and the frequency of concurrent outbreaks in ICUs and general wards increased over time (p<0.01). The median outbreak duration rose from 43.5 days before the coronavirus disease 2019 (COVID-19) pandemic (2017-2019) to 79.5 days during the pandemic (2020-2022) (p=0.01), and the median number of patients associated with each outbreak increased from 5.0 to 6.0 (p=0.03). Frequently recommended interventions included employee education (38.1%), and 3 or more measures were proposed for 45.2% of outbreaks. CONCLUSION: In the Republic of Korea, CPE outbreaks have been consistently dominated by K. pneumoniae and KPC. The size of these outbreaks increased during the COVID-19 pandemic. Our findings highlight the need for continuing efforts to control CPE outbreaks using a multimodal approach, while considering their epidemiology.

Epidemiology and Risk Factors of Carbapenemase-Producing Enterobacteriaceae Acquisition and Colonization at a Korean Hospital over 1 Year.

Background: Carbapenemase-producing Enterobacteriaceae (CPE) are known to be primarily responsible for the increasing spread of carbapenem-resistant Enterobacteriaceae and have therefore been targeted for preventing transmission and appropriate treatment. This study aimed to describe the clinical and epidemiological characteristics and risk factors of CPE infection in terms of acquisition and colonization. Methods: We examined patients' hospital data, including active screening on patients' admission and in intensive care units (ICUs). We identified risk factors for CPE acquisition by comparing the clinical and epidemiological data of CPE-positive patients between colonization and acquisition groups. Results: A total of 77 CPE patients were included (51 colonized and 26 acquired). The most frequent Enterobacteriaceae species was Klebsiella pneumoniae. Among CPE-colonized patients, 80.4% had a hospitalization history within 3 months. CPE acquisition was significantly associated with treatment in an ICU [adjusted odds ratio (aOR): 46.72, 95% confidence interval (CI): 5.08-430.09] and holding a gastrointestinal tube (aOR: 12.70, 95% CI: 2.61-61.84). Conclusions: CPE acquisition was significantly associated with ICU stay, open wounds, holding catheters or tubes, and antibiotic treatment. Active CPE screening should be implemented on admission and periodically for high-risk patients.

Contributions and Limitations of National Cervical Cancer Screening Program in Korea: A Retrospective Observational Study.

PURPOSE: The purpose of this study was to evaluate the contributions and limitations of the cervical cancer screening test with accuracy in Korea. METHODS: This was a retrospective observational study. The study population consisted of all participants who underwent cervical cancer screening test from 2009 to 2014. The data were obtained from National Health Information Database (NHID) which represents medical use records of most Koreans. As the indices for contributions and limitations of the screening test, crude detection rate, incidence rate of interval cancer, sensitivity, specificity, and positive predictive value were used. RESULTS: The crude detection rate of screening test per 100,000 participants increased from 100.7 in 2009 to 102.1 in 2014. The incidence rate of interval cancer per 100,000 negatives decreased from 13.0 in 2009 to 10.2 in 2014. The sensitivities of screening test were 88.7% in 2009 and 91.2% in 2014, and the specificities were 98.5% in 2009 and 97.7% in 2014. The positive predictive value of screening decreased from 6.2% in 2009 to 4.3% in 2014. CONCLUSION: The Korean national cervical cancer screening program has improved in accuracy and has contributed to detection of early stage of cervical cancer over the years. Along with efforts to promote participation in cancer screening programs, quality control over the screening program should be enhanced.

Defining the activities of publicness for Korea's public community hospitals using the Delphi method.

This study aims to identify which activities of a public community hospital (PHC) should be included in their definition of publicness and tries to achieve a consensus among experts using the Delphi method. We conduct 2 rounds of the Delphi process with 17 panel members using a developed draft of tentative activities for publicness including 5 main categories covering 27 items. The questions remain the same in both rounds and the applicability of each of the 27 items to publicness is measured on a 9-point scale. If the participants believe government funding is needed, we ask how much they think the government should support each item on a 0% to 100% scale. After conducting 2 rounds of the Delphi process, 22 out of the 27 items reached a consensus as activities defining the publicness of the PHCs. Among the 5 major categories, in category C, activities preventing market failure, all 10 items were considered activities of publicness. Nine of these were evaluated as items that should be compensated at 100% of total financial loss by the Korean government. Throughout results, we were able to define the activities of the PCH that encompassed its publicness and confirm that there are "good deficits" in the context of the PCHs. Thus, some PCH deficits are unavoidable and not wasted as these monies support a necessary role and function in providing public health. The Korean government should therefore consider taking actions such as exempting such "good deficits" or providing additional financial aid to reimburse the PHCs for "good deficits."

Quantification of Transfusion Recipients at Risk of Receiving Hepatitis B Virus-Contaminated Blood Components: A Korean Study.

Although there are lots of studies about the risk for the hepatitis B virus infection such as the residual risk for donated blood, there is no research on the risk of HBV infection, from the viewpoint of recipients in Korea. Using the data about HBsAg status of donated blood in 2008 and 2009, the distribution of blood components from the claim data of health insurance in 2009, the distribution of HBsAg and HBsAb of recipients, and some assumptions, we quantified the number of recipients in Korea that might be expected to receive HBV-contaminated blood components, as a proxy index for HBV infection by transfusion in 2009. Of the 376,211 recipients, the number who might be expected to receive blood components with HBV in 2009 was 23.2 (95 % CI 13.6, 36.8) in the basic model, 43.2 (95 % CI 25.4, 68.7) in extended model I, 55.2 (95 % CI 32.5, 87.7) in extended model II and 101.6 (95 % CI 59.8, 161.4) in extended model III. The number of HBV-positive samples per 100,000 transfused units was 0.6 in the basic model (95 % CI 0.3, 0.9), 1.1 in extended model I (95 % CI 0.6, 1.8), 1.4 in extended model II (95 % CI 0.8, 2.2), and 2.6 in extended model III (95 % CI 1.5, 4.1). This study showed that a few recipients might receive HBV-contaminated blood component by transfusion. These results could be used as a scientific evidence for health policy on HBV transfusion infection.

Association Between Smoking and Physician-Diagnosed Stroke and Myocardial Infarction in Male Adults in Korea.

To evaluate the association between smoking and physician-diagnosed stroke and myocardial infarction, this study used Community Health Survey data from 2009 on 92,082 males over the age of 30 years. Using multiple logistic regression, association index between smoking and physician-diagnosed stroke and myocardial infarction was calculated after adjusting the effects of age, hypertension, and diabetes. The odds ratios (95% confidence interval) of the physician-diagnosed stroke and myocardial infarction in the smoking group were 1.12 (1.02-1.24) and 1.21 (1.06-1.38) compared to the non-smoking group. The values of the physician-diagnosed stroke and myocardial infarction were 0.84 (0.74-0.94) and 0.96 (0.82-1.12) in the current-smoking subgroup, 1.38 (1.24-1.53) and 1.45 (1.26-1.67) in the ex-smoking subgroup, 1.39 (1.18-1.63) and 1.85 (1.53-2.24) in the 10- to 19-year smokers groups, 1.39 (1.22-1.58) and 1.36 (1.15-1.60) in the 30- to 40-year smokers groups, and 0.53 (0.44-0.63) and 0.47 (0.36-0.63) in those who had smoked for over 50 years. These results showed smoking was a risk factor for stroke and myocardial infarction in Korean males. This objective evidence should guide policy-making and public health interventions in the fields of smoking prevention and prohibition.

Factors affecting the validity of self-reported data on health services from the community health survey in Korea.

PURPOSE: As a follow-up for the validity study of Community Health Surveys (CHSs), the purpose of this study was to evaluate the factors affecting the accuracy of CHSs by investigating subjects' characteristics. MATERIALS AND METHODS: We used data from 11,217 participants (aged 19 years or older) who had participated in the CHS, conducted by a local government in 2008 and analyzed the variables affecting the sensitivity and specificity of hospitalization and outpatient visit. RESULTS: Multivariate logistic regression analysis showed that, factors related with the sensitivity of hospitalization and outpatient visit questions were gender, age, marital status, chronic diseases, medical checkup, the subjective health status and necessary medical services. Factors related with the specificity were gender, marital status, educational background, chronic diseases, medical checkup, alcohol consumption, necessary medical services and sadness. CONCLUSION: This study revealed the subject-related factors associated with the validity of the CHS. Efforts to improve the sensitivity and the specificity from self-report questionnaires should consider how the characteristics of subjects may affect their responses.