Beneficial Effect of Statins in COVID-19-Related Outcomes-Brief Report: A National Population-Based Cohort Study.

OBJECTIVE: Although statins are widely prescribed lipid-lowering drugs, there are concerns about the safety of their use in the context of coronavirus disease 2019 (COVID-19), since statins increase the expression of ACE2 (angiotensin-converting enzyme 2). This study aimed to disclose the association between statins and 60-day COVID-19 mortality. Approach and Results: All patients hospitalized with laboratory-confirmed COVID-19 were enrolled in this study from January 19 to April 16, 2020, in Korea. We evaluated the association between the use of statins and COVID-19-related mortality in the overall and the nested 1:2 propensity score-matched study. Furthermore, a comparison of the hazard ratio for death was performed between COVID-19 patients and a retrospective cohort of patients hospitalized with pneumonia between January and June 2019 in Korea. The median age of the 10 448 COVID-19 patients was 45 years. Statins were prescribed in 533 (5.1%) patients. After adjusting for age, sex, and comorbidities, Cox regression showed a significant decrease in hazard ratio associated with the use of statins (hazard ratio, 0.637 [95% CI, 0.425-0.953]; P=0.0283). Moreover, on comparing the hazard ratio between COVID-19 patients and the retrospective cohort of hospitalized pneumonia patients, the use of statins showed similar benefits. CONCLUSIONS: The use of statins correlates significantly with lower mortality in patients with COVID-19, consistent with the findings in patients with pneumonia. Graphic Abstract: A graphic abstract is available for this article.

Clinical Characteristics of 40 Patients Infected With the SARS-CoV-2 Omicron Variant in Korea.

Since severe acute respiratory syndrome-coronavirus-2 variant B.1.1.529 (omicron) was first reported to the World Health Organization on November 24, 2021, the cases of the omicron variant have been detected in more than 90 countries over the last month. We investigated the clinical and epidemiological characteristics of the first 40 patients with the omicron variant who had been isolated at the National Medical Center in South Korea during December 4-17, 2021. The median age of the patients was 39.5 years. Twenty-two patients (55%) were women. Seventeen patients (42.5%) were fully vaccinated, and none were reinfected with the omicron. Eighteen (45%) had recent international travel history. Half of the patients (19, 47.5%) were asymptomatic, while the others had mild symptoms. Six patients (15%) showed lung infiltrations on chest image; however, none required supplemental oxygen. These mild clinical features are consistent with recent case reports on the omicron variant from other countries.

Changes in Anxiety Level and Personal Protective Equipment Use Among Healthcare Workers Exposed to COVID-19.

BACKGROUND: The relationship between changes in anxiety levels and personal protective equipment (PPE) use is yet to be evaluated. The present study assessed this relationship among healthcare workers (HCWs) involved in the care of patients with coronavirus disease 2019 (COVID-19). METHODS: An online survey was conducted in a municipal hospital with 195 nationally designated negative pressure isolation units in Korea. Anxiety level was measured using the self-rating anxiety scale (SAS), and changes in anxiety levels were assessed based on the time when COVID-19 vaccine was introduced in March 2021 in Korea. Monthly PPE usage between June 2020 and May 2021 was investigated. RESULTS: The mean SAS score (33.25 ± 5.97) was within normal range and was lower than those reported in previous studies conducted before COVID-19 vaccination became available. Among the 93 HCWs who participated, 64 (68.8%) answered that their fear of contracting COVID-19 decreased after vaccination. The number of coveralls used per patient decreased from 33.6 to 0. However, a demand for more PPE than necessary was observed in situations where HCWs were exposed to body fluids and secretions (n = 38, 40.9%). Excessive demand for PPE was not related to age, working experience, or SAS score. CONCLUSION: Anxiety in HCWs exposed to COVID-19 was lower than it was during the early period of the pandemic, and the period before vaccination was introduced. The number of coveralls used per patient also decreased although an excessive demand for PPE was observed.

Booster BNT162b2 COVID-19 Vaccination Increases Neutralizing Antibody Titers Against the SARS-CoV-2 Omicron Variant in Both Young and Elderly Adults.

Concerns about the effectiveness of current vaccines against the rapidly spreading severe acute respiratory syndrome-coronavirus-2 omicron (B.1.1.529) variant are increasing. This study aimed to assess neutralizing antibody activity against the wild-type (BetaCoV/Korea/KCDC03/2020), delta, and omicron variants after full primary and booster vaccinations with BNT162b2. A plaque reduction neutralization test was employed to determine 50% neutralizing dilution (ND50) titers in serum samples. ND50 titers against the omicron variant (median [interquartile range], 5.3 [< 5.0-12.7]) after full primary vaccination were lower than those against the wild-type (144.8 [44.7-294.0]) and delta (24.3 [14.3-81.1]) variants. Furthermore, 19/30 participants (63.3%) displayed lower ND50 titers than the detection threshold (< 10.0) against omicron after full primary vaccination. However, the booster vaccine significantly increased ND50 titers against BetaCoV/Korea/KCDC03/2020, delta, and omicron, although titers against omicron remained lower than those against the other variants (P < 0.001). Our study suggests that booster vaccination with BNT162b2 significantly increases humoral immunity against the omicron variant.

Waning Antibody Responses in Asymptomatic and Symptomatic SARS-CoV-2 Infection.

We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response.

Suboptimal medication adherence in young women living with HIV infection: a Korean nationwide claims study.

The epidemiological characteristics of women living with human immunodeficiency virus (HIV) infection have gained little attention as the numbers are small compared with men living with HIV in the Republic of Korea. However, these data are important to achieve effective HIV infection control and to consider the influence of socioeconomic status on HIV transmission. This study utilized the claims database of the Korean National Health Insurance system to analyze women with a newly diagnosed HIV infection during the period 2009-2016. Adherence to antiretroviral agents was calculated using the medication possession ratio. Among 677 women with a newly diagnosed HIV infection, 219 (32.4%) were over 50 years of age; 291 (43.0%) were identified as having acquired immune deficiency syndrome (AIDS). A total of 99 women (14.6%) were National Medical Aid beneficiaries. Optimal medical adherence >95% was found in 62.2% of subjects. Teenage years (odds ratio(OR) 14.9, 95% confidence interval (95CI) 4.9-44.8), AIDS (OR 1.7, 95CI 1.2-2.3), and low economic status requiring National Medical Aid (OR 3.0, 95CI 2.0-4.6) were associated to adherence. Diagnosis prior to 2012 was also associated with poor adherence. In women, particularly young patients with low economic status, extra attention is required to enhance adherence to prescribed medication.

Three-year outcome of rapid HIV testing at public health centers in Seoul, Republic of Korea: a short report.

Before 2014, the only test used for anonymous voluntary human immunodeficiency virus (HIV) screening at public health centers (PHCs) in the Republic of Korea was an enzyme-linked immunosorbent assay (ELISA), which takes around 3 days to obtain results. In 2014, to encourage voluntary anonymous HIV screening tests, the Seoul Metropolitan Government adopted a rapid HIV screening test at PHCs. The rapid HIV screening test was introduced at four PHCs in 2014 and all 25 PHCs after 2015. We compared the numbers of HIV screening tests and confirmed positive individuals before and after introduction of the rapid HIV screening test. In 2012-2013, before the introduction of rapid HIV screening test, an average of 330 HIV screening tests were performed monthly (355 in 2012 and 305 in 2013) and 69 individuals were confirmed to have HIV in 2012 and 93 in 2013. After the introduction of the rapid HIV screening test, anonymous voluntary HIV screening increased to a monthly average of 447 tests in 2014, 2099 in 2015, and 2409 in 2016. These identified 38 new cases in 2014, 116 in 2015, and 143 in 2016. Adoption of the rapid HIV screening test has increased the number of HIV screening tests and confirmed cases.

High Prevalence of Human Immunodeficiency Virus Infection among Inmates in Korean Correctional Facilities.

BACKGROUND: Epidemiological data are crucial in designing policies for the control of human immunodeficiency virus (HIV) infections. There is a lack of data on the epidemiology of HIV in Korean correctional facilities such as jails and prisons. METHODS: Clinical characteristics of the study population were collected through a medical record review. RESULTS: The number of people with HIV infection were 83 and the HIV infection prevalence in correctional facilities of Korea was 0.15%. Among them, 10 (12.0%) were diagnosed with the infection when they were incarcerated. The number of drug users was 38 (45.8%). Syphilis-HIV coinfection was observed in 21 (25.3%) patients. Individuals from the group comprising the drug users were more likely to belong to the lesbian, gay, bisexual, transgender, queer (LGBTQ) community, and had a higher incidence of psychological disorders (31.6% vs. 11.1%, P = 0.029; 50.0% vs. 28.9%, P = 0.049, respectively). CONCLUSION: Inmates of correctional facilities showed a five times higher prevalence of HIV infection in Korea, nearly half of whom were drug users.

Redundant combinations of antianaerobic antimicrobials: impact of pharmacist-based prospective audit and feedback and prescription characteristics.

This study aimed to evaluate the impact of the intervention targeting the redundant combination of antianaerobic antimicrobials on its incidence and associated antimicrobial consumption. To reveal the characteristics of the combination and the change in the related workload over time was an additional aim of the study. The combinations of metronidazole or clindamycin with antianaerobic antimicrobials were classified into redundant or acceptable, according to the target indications. A pharmacist-based prospective audit and feedback targeting the redundant antianaerobic combination was conducted. Segmented regression analysis was performed to evaluate the impact of the intervention. As a quantitative index of the interventional activity, the change in the number of signed consultation notes was evaluated. After the initiation of the intervention, the median monthly cumulative incidence of the redundant combination decreased from 5.29 (Interquartile range [IQR] 4.94-5.70) to 3.33 (IQR 2.87-3.71) (p < 0.001) per 1000 admissions per month. The consumption of concurrently administered metronidazole and clindamycin decreased from 3.34 (IQR 2.97-4.10) to 1.74 (IQR 1.19-1.93) (p < 0.001) per 1000 patient-days per month. Segmented regression analysis revealed that the monthly cumulative incidence decreased by 28.5% after the initiation of the intervention (change in level - 1.640, p = 0.019) and the monthly consumption decreased by 33.9% (change in level - 1.409, p = 0.009). The number of consultation notes per 1000 admissions per month decreased over time (regression coefficient - 0.004, p < 0.001). The pharmacist-based intervention significantly reduced the incidence and associated antimicrobial consumption of the redundant antianaerobic combination. The overall related workload reduced steadily over time.

Prevalence of cryptococcal antigenemia in hospitalized patients with liver cirrhosis.

The benefits of screening for cryptococcal antigenemia and of preemptive antifungal treatment in HIV-infected patients have been proven. Liver cirrhosis is an important risk factor for cryptococcal infections. Cryptococcal infections are rapidly fatal in patients with liver cirrhosis, especially when diagnosis is delayed. However, screening for cryptococcal antigenemia has not been investigated in these patients. The aim of this study was to investigate the prevalence of cryptococcal antigenemia in hospitalized patients with liver cirrhosis. This prospective study was conducted at Seoul National University Hospital from July 2017 to January 2018. We included patients with liver cirrhosis who were admitted regardless of symptoms or signs suggesting cryptococcal infections. The severity of cirrhosis was evaluated from Child-Pugh and model for end-stage liver disease (MELD) scores. Serum cryptococcal antigenemia was determined using a latex agglutination test. A total of 294 patients were included in the analysis, comprising 104 (35.4%), 100 (34.0%), and 90 (30.6%) patients in Child-Pugh classes A, B, and C, respectively. There were 21 cases of spontaneous bacterial peritonitis, and 14 of hepatic encephalopathy, but none of cryptococcal peritonitis or meningitis. In addition, none of the patient specimens tested positive in the serum cryptococcal latex agglutination test (one-sided 97.5% confidence interval, 0% ∼ 1.2%). Liver cirrhosis is a major risk factor for cryptococcal infections, but the prevalence of serum cryptococcal antigen positivity in patients with liver cirrhosis is very low. Therefore, screening for cryptococcal antigenemia and preemptive antifungal treatment in cirrhotic patients might not be beneficial.

Association of HIV-syphilis coinfection with optimal antiretroviral adherence: a nation-wide claims study.

Condomless sex is not totally discouraged after achieving undetectable human immunodeficiency virus (HIV) load, but the prevalence of sexually transmitted diseases (STDs) in the group is unknown. This study was retrospective in nature, using the claims database of the National Health Insurance system from 2008 to 2016. The clinical characteristics of people living with HIV with or without syphilis coinfection were analyzed. People with HIV and syphilis coinfection were divided into two groups according to antiretroviral therapy adherence, as optimal and suboptimal adherence groups by a medication possession ratio of 95%. Of the 9393 people living with HIV, 4536 (48.3%) were diagnosed with syphilis coinfection. Optimal adherence was associated with syphilis coinfection (odds ratio [OR] 1.18; 95% confidence interval [95CI] 1.08-1.30; p = .001). This suggests that unsafe sex occurs regardless of medication adherence. Being male, bacterial/protozoa STDs, and genital herpes virus infection were also risk factors for HIV-syphilis coinfection. Although HIV is unlikely to be transmittable when viral load is controlled, consistent use of condoms is necessary to prevent infection with syphilis.

Predictive scoring models for persistent gram-negative bacteremia that reduce the need for follow-up blood cultures: a retrospective observational cohort study.

BACKGROUND: Although the risk factors for positive follow-up blood cultures (FUBCs) in gram-negative bacteremia (GNB) have not been investigated extensively, FUBC has been routinely carried out in many acute care hospitals. We attempted to identify the risk factors and develop a predictive scoring model for positive FUBC in GNB cases. METHODS: All adults with GNB in a tertiary care hospital were retrospectively identified during a 2-year period, and GNB cases were assigned to eradicable and non-eradicable groups based on whether removal of the source of infection was possible. We performed multivariate logistic analyses to identify risk factors for positive FUBC and built predictive scoring models accordingly. RESULTS: Out of 1473 GNB cases, FUBCs were carried out in 1268 cases, and the results were positive in 122 cases. In case of eradicable source of infection, we assigned points according to the coefficients from the multivariate logistic regression analysis: Extended spectrum beta-lactamase-producing microorganism (+ 1 point), catheter-related bloodstream infection (+ 1), unfavorable treatment response (+ 1), quick sequential organ failure assessment score of 2 points or more (+ 1), administration of effective antibiotics (- 1), and adequate source control (- 2). In case of non-eradicable source of infection, the assigned points were end-stage renal disease on hemodialysis (+ 1), unfavorable treatment response (+ 1), and the administration of effective antibiotics (- 2). The areas under the curves were 0.861 (95% confidence interval [95CI] 0.806-0.916) and 0.792 (95CI, 0.724-0.861), respectively. When we applied a cut-off of 0, the specificities and negative predictive values (NPVs) in the eradicable and non-eradicable sources of infection groups were 95.6/92.6% and 95.5/95.0%, respectively. CONCLUSIONS: FUBC is commonly carried out in GNB cases, but the rate of positive results is less than 10%. In our simple predictive scoring model, zero scores-which were easily achieved following the administration of effective antibiotics and/or adequate source control in both groups-had high NPVs. We expect that the model reported herein will reduce the necessity for FUBCs in GNB cases.

Estimation of the Number of HIV Infections and Time to Diagnosis in the Korea.

BACKGROUND: Statistical data of undiagnosed people living with human immunodeficiency virus (PLHIV) are of great importance to human immunodeficiency virus (HIV) infection control. This study estimated the total number of PLHIV using nationwide claims data. METHODS: This study used data of the incident HIV cases identified by the National Health Insurance System between 2009 and 2015. The number of patients with acquired immune deficiency syndrome (AIDS) was identified by diagnoses or prescription records. The estimated number of PLHIV and the time to diagnosis were calculated from the incident numbers of HIV and AIDS cases using the HIV Modeling Tool of the European Center for Disease Prevention and Control. RESULTS: Between 2009 and 2015, a total of 7,033 PLHIV and 2,899 AIDS patients were diagnosed. In 2009, the number of incident HIV cases was 873 (460 AIDS patients), increasing to 995 (337 AIDS patients) in 2015. Besides, the estimated number of prevalent cases was 10,753 in 2009, compared to 14,880 in 2015. Patients visiting health facilities accounted for 42.9% (4,616/10,753) in 2009 and 64.1% (9,544/14,880) in 2015. In 2009, there were 8,363 (77.8%) undiagnosed HIV cases, experiencing a decline to 6,215 (41.8%) in 2015. It took a mean of 6.96 years to diagnose after HIV infection. CONCLUSION: This study estimates the total burden of HIV infection in Korea for the first time using an internationally recognized HIV modeling tool. Claims data can be used to estimate the number of undiagnosed cases by identifying the total number of PLHIV and AIDS patients visiting health facilities.

The Importance of Proper History Taking: Asking a Fever Pattern in Patients with Vivax Malaria.

Characteristic fever patterns of malarial infection are clues for diagnosis. However, checking fever patterns in febrile patients has been usually missed, and unnecessary tests have been performed. We reviewed electrical medical record to check whether history-taking included questions on fever pattern in febrile patients. Main outcomes were time interval between visit and diagnosis of vivax malaria and proportion of patients who had taken unnecessary tests. Among 134 vivax malarial patients, asking about fever pattern was done in 64 (47.8%). Median time interval between visit and diagnosis was significantly shorter in patients whose fever pattern was asked than those not asked (3.2 hours vs. 18.6 hours; P < 0.001). Unnecessary diagnostic tests were conducted in 27% (17/64) of patients asked about fever pattern and 71% (50/70) in patients not asked (P < 0.001). Proper history-taking can reduce time elapsed for diagnosis and performing unnecessary diagnostic tests in vivax malaria.

Clinical Score System to Differentiate Severe Fever with Thrombocytopenia Syndrome Patients from Patients with Scrub Typhus or Hemorrhagic Fever with Renal Syndrome in Korea.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with high mortality in East Asia. This study aimed to develop, for primary care providers, a prediction score using initial symptoms and basic laboratory blood tests to differentiate between SFTS and other endemic zoonoses in Korea. METHODS: Patients aged ≥ 18 years diagnosed with endemic zoonoses during a 3-year period (between January 2015 and December 2017) were retrospectively enrolled from 4 tertiary university hospitals. A prediction score was built based on multivariate logistic regression analyses. RESULTS: Of 84 patients, 35 with SFTS and 49 with other endemic zoonoses were enrolled. In multivariate logistic regression analysis, independent predictors of SFTS included neurologic symptoms (odds ratio [OR], 12.915; 95% confidence interval [CI], 2.173-76.747), diarrhea (OR, 10.306; 95% CI, 1.588-66.895), leukopenia (< 4,000/mm³) (OR, 19.400; 95% CI, 3.290-114.408), and normal C-reactive protein (< 0.5 mg/dL) (OR, 24.739; 95% CI, 1.812-337.742). We set up a prediction score by assigning one point to each of these four predictors. A score of ≥ 2 had 82.9% sensitivity (95% CI, 71.7%-87.5%) and 95.9% specificity (95% CI, 88.0%-99.2%). The area under the curve of the clinical prediction score was 0.950 (95% CI, 0.903-0.997). CONCLUSION: This study finding suggests a simple and useful scoring system to predict SFTS in patients with endemic zoonoses. We expect this strategic approach to facilitate early differentiation of SFTS from other endemic zoonoses, especially by primary care providers, and to improve the clinical outcomes.

Clinical Course and Outcomes of Patients with Severe Acute Respiratory Syndrome Coronavirus 2 Infection: a Preliminary Report of the First 28 Patients from the Korean Cohort Study on COVID-19.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected pneumonia emerged in Wuhan, China in December 2019. In this retrospective multicenter study, we investigated the clinical course and outcomes of novel coronavirus disease 2019 (COVID-19) from early cases in Republic of Korea. METHODS: All of the cases confirmed by real time polymerase chain reaction were enrolled from the 1st to the 28th patient nationwide. Clinical data were collected and analyzed for changes in clinical severity including laboratory, radiological, and virologic dynamics during the progression of illness. RESULTS: The median age was 40 years (range, 20-73 years) and 15 (53.6%) patients were male. The most common symptoms were cough (28.6%) and sore throat (28.6%), followed by fever (25.0%). Diarrhea was not common (10.7%). Two patients had no symptoms. Initial chest X-ray (CXR) showed infiltration in 46.4% of the patients, but computed tomography scan confirmed pneumonia in 88.9% (16/18) of the patients. Six patients (21.4%) required supplemental oxygen therapy, but no one needed mechanical ventilation. Lymphopenia was more common in severe cases. Higher level of C-reactive protein and worsening of chest radiographic score was observed during the 5-7 day period after symptom onset. Viral shedding was high from day 1 of illness, especially from the upper respiratory tract (URT). CONCLUSION: The prodromal symptoms of COVID-19 were mild and most patients did not have limitations of daily activity. Viral shedding from URT was high from the prodromal phase. Radiological pneumonia was common from the early days of illness, but it was frequently not evident in simple CXR. These findings could be plausible explanations for the easy and rapid spread of SARS-CoV-2 in the community.

Efficacy of Intranasal Administration of the Recombinant Endolysin SAL200 in a Lethal Murine Staphylococcus aureus Pneumonia Model.

SAL200 is derived from a phage endolysin and is a novel candidate drug for the treatment of Staphylococcus aureus infection. We investigated the efficacy of the recombinant endolysin SAL200 in a lethal murine pneumonia model. Lethal pneumonia was established by intranasally administering a methicillin-susceptible (Newman) or methicillin-resistant (LAC) S. aureus strain into BALB/c mice. The mice were treated with a single intranasal administration of SAL200 or phosphate-buffered saline at 2 h after S. aureus infection. The survival rates were recorded until 60 h after the bacterial challenge. The bacterial loads in the lungs and blood, histopathology of lung tissues, and serum cytokine levels were evaluated following the S. aureus challenge. The SAL200-treated group and control group exhibited 90% to 95% and 10% to 40% survival rates, respectively. The bacterial loads in the lungs of the SAL200-treated group were significantly lower by ∼10-fold than those of the control group as early as 1 h after treatment. Histopathologic recovery of pneumonia was observed in the SAL200-treated mice. The cytokine levels were comparable between groups. These results suggest that direct administration of SAL200 into the lungs could be a potential adjunct treatment against severe pneumonia caused by S. aureus.

A Prospective Cohort Study of Durations of Staphylococcus aureus Bacteremia According to Different Phenotypes and a New Concept of Persistent Bacteremia.

The purpose of this study was to describe and compare the duration of Staphylococcus aureus bacteremia (SAB) according to methicillin resistance and the primary foci of infection. We also aimed to newly define persistent SAB considering these results. Nonduplicated episodes of SAB in patients aged ≥15 years from 14 hospitals in the Republic of Korea were analyzed between January 2009 and February 2018. The duration of SAB was defined as the number of days from the time of administration of an antibiotic to which the isolate was susceptible after the onset of SAB to the last day of a positive blood culture for S. aureus SAB durations were described and compared based on methicillin resistance and the primary foci of infection. Cases in the top quartile for the duration of bacteremia in the respective clinical context were classified as newly defined persistent SAB, and its association with in-hospital mortality was evaluated. A total of 1,917 cases were analyzed. The duration of SAB was longer in patients with methicillin-resistant SAB (MRSAB; n = 995) than in patients with methicillin-susceptible SAB (MSSAB; n = 922) (median duration, 1 day [interquartile range, 1 to 3 days] for MSSAB and 1 day [interquartile range, 0 to 5 days] for MRSAB; P < 0.001). The duration of bacteremia was longer in patients with endocarditis and bone and joint, endovascular, and surgical site infections and was shorter in patients with skin and soft tissue infections. Newly defined persistent SAB was independently associated with in-hospital mortality (adjusted odds ratio, 1.97; 95% confidence interval, 1.54 to 2.53; P < 0.001). The durations of SAB were dependent on methicillin resistance and the primary foci of infection, and considering these contexts, persistent SAB was significantly associated with in-hospital mortality.

Prospective evaluation of a rapid antimicrobial susceptibility test (QMAC-dRAST) for selecting optimal targeted antibiotics in positive blood culture.

OBJECTIVES: MALDI-TOF MS has been successfully used for empirical antibiotic selection. However, limited data are available regarding the usefulness of MALDI-TOF MS in common resistant organisms compared with rapid antimicrobial susceptibility testing (AST). We prospectively evaluated the usefulness of rapid AST, compared with MALDI-TOF MS, for optimal antibiotic selection by infectious disease (ID) physicians in patients with bacteraemia including polymicrobial infection. METHODS: Three hundred and fifty-nine patients with positive blood culture were included for analysis. ID physicians prospectively decided on antibiotic regimens with consensus at each timepoint of receiving results of Gram stain, MALDI-TOF MS and rapid AST, the last of which was performed using QMAC-dRAST. RESULTS: ID physicians with MALDI-TOF MS results chose optimal targeted antibiotics in 255 (71.0%) cases, with appropriate antibiotic selection in 303 (84.4%) cases. The proportion of optimal targeted antibiotic selection and appropriate antibiotic selection was significantly lower for resistant strains than for susceptible strains [62.5% versus 79.2% (P < 0.001) and 68.2% versus 100% (P < 0.001), respectively]. QMAC-dRAST results led to optimal antibiotic treatment in 95 (91.3%) of the 104 cases receiving non-optimal targeted antibiotics. Optimal targeted treatments based on QMAC-dRAST results were possible in 322 (98.2%) of the 328 cases with monobacterial infection and in 345 (96.1%) of the 359 cases with monobacterial and polymicrobial infection. CONCLUSIONS: MALDI-TOF MS has a high chance of failure in guiding ID physicians to optimal antibiotics, especially against resistant organisms. With increasingly common resistant organisms, rapid AST is needed to identify optimal targeted antibiotics early in bacteraemia.

Increasing varicella incidence rates among children in the Republic of Korea: an age-period-cohort analysis.

In the Republic of Korea, despite the introduction of one-dose universal varicella vaccination in 2005 and achieving a high coverage rate of 98.9% in 2012, the incidence rate has been increased sevenfold. This study aimed to investigate time trends of varicella incidence rate, assessing the age, period and birth cohort effects. We used national data on the annual number of reported cases from 2006 to 2017. A log-linear Poisson regression model was used to estimate age-period-cohort effects on varicella incidence rate. From 2006 to 2017, the incidence of varicella increased from 22.5 cases to more than 154.8 cases per 100 000. Peak incidence has shifted from 4 to 6 years old. The estimated period and cohort effects showed significant upward patterns, with a linear increasing trend by net drift. There has been an increase in the incidence among the Korean population regarding period and cohort despite the universal vaccination of varicella vaccine. Our data suggest the need for additional studies to address the current gap in herd immunity.