Candida auris was initially isolated from a Japanese patient, and is now an emerging fungus species owing to its long-term colonization capabilities and high resistance to antifungal drugs. However, the domestic epidemiology of C. auris in Japan remains unknown. In this study, we collected C. auris isolates from hospitals, public health centers, and public health institutes in Japan based on the administrative liaison. Moreover, we also obtained isolates from three nongovernmental laboratory companies. Seventy C. auris isolates were collected during the study period. These isolates predominantly originated from clinical ear discharge samples. Clade determination based on the internal transcribed spacer-D1/D2 regions and CauMT1 locus revealed that almost all isolates belonged to clade II; however, one ear discharge-derived isolate belonged to clade I, confirmed by whole genome sequencing. Regarding drug susceptibility, 20% of the isolates were resistant to fluconazole; however, none of the isolates exhibited polyene or echinocandin resistance. In summary, the C. auris isolates collected in Japan were generally derived from ear discharge samples and belonged to clade II. However, ear discharge-derived isolates may not belong exclusively to clade II. Although no invasive cases were reported during the study period, continuing surveillance programs to clearly describe the domestic epidemiology is necessary.

This study evaluated the prevalence of antibodies against eight viruses and pertussis in serum samples collected from 191 pregnant women in 2022. Serum IgG antibodies were measured against the following viruses and pertussis toxin (PT): measles virus (MV), rubella virus (RV), mumps virus (MuV), varicella–zoster virus (VZV), herpes simplex virus (HSV), cytomegalovirus (CMV), Epstein–Barr virus (EBV), and human parvovirus B19 (PVB19). Infection history and immunization status for vaccine-preventable diseases, including measles, rubella, mumps, varicella, and pertussis, were simultaneously obtained via a questionnaire. Findings were compared with those of our previous studies using umbilical cord blood samples from 2001–2002 and 2013 (eight viruses) and from 2016–2018 (pertussis). In 2022, seroprevalence rate were 88.5% for MV, 86.4% for RV, 46.1% for MuV, 91.1% for VZV, 47.6% for HSV, 61.3% for CMV, 93.7% for EBV, 69.6% for PVB19, and 63.4% for PT. Seroprevalence declined over time for all diseases except PVB19 and pertussis. Mean IgG antibody titers were significantly lower, despite significantly higher vaccination coverage rates in the four vaccine-preventable viral diseases than in previous studies. Therefore, ongoing monitoring of seroprevalence trends for these pathogens in pregnant women is essential.

The Elecsys ^® HCV Duo (HCV Duo) detects antibodies to HCV (Duo/anti-HCV) and HCV core antigen (Duo/HCV-Ag), offering an efficient, cost-effective, and rapid way to screen for hepatitis C virus (HCV). We evaluated HCV Duo's utility in Japan. We analyzed 373 samples (120 HCV RNA-detectable and 253 HCV RNA-undetectable) from chronic hepatitis C (CHC) patients. Duo/anti-HCV sensitivity was assessed using conventional assays. Duo/HCV-Ag sensitivity and specificity were evaluated based on HCV RNA levels. We categorized 153 untreated CHC patients at Nagoya City University Hospital (NCUH) between 2019 and 2023 by HCV RNA levels. HCV Duo showed 100% sensitivity (373/373) for Duo/anti-HCV and 99.2% specificity (251/253) for Duo/HCV-Ag in resolved infection. Duo/HCV-Ag exhibited 55.0% sensitivity (66/120) in active HCV infections. For HCV RNA levels ≤4.0, 4.1–5.5, and ≥5.6 log IU/mL, Duo/HCV-Ag detection rates were 20.5% (9/44), 33.3% (7/21), and 87.3% (48/55), respectively. At NCUH, 71.2% (109/153) of patients had HCV RNA levels ≥5.6 log IU/mL, while 2.6% (4/153) and 26.1% (40/153) had levels ≤4.0 and 4.1–5.5 log IU/mL, respectively. Duo/HCV-Ag performance improves with higher HCV RNA levels, particularly ≥5.6 log IU/mL. HCV RNA testing is recommended for patients positive for Duo/anti-HCV but negative for Duo/HCV-Ag. Duo/HCV-Ag-positive patients should be referred to hepatologists for further evaluation and treatment.

Mycobacterium tuberculosis is the causative agent of tuberculosis. Globally, it is one of the most significant bacteria in terms of responsibility for human mortality. To prevent the transmission of tuberculosis, it is essential to properly sterilize environments contaminated with Mycobacterium. For sterilization, sodium hypochlorite is commonly used to kill pathogens. However, M. tuberculosis usually shows high resistance to sodium hypochlorite. In this study, we compared the bactericidal activity of chlorous acid and sodium hypochlorite against M. tuberculosis in the presence or absence of artificial saliva. When 7.0 log CFU/mL of M. tuberculosis was treated with different concentrations of sodium hypochlorite or chlorous acid, it was found that, while 20,000 ppm of sodium hypochlorite was needed to reduce the pathogen below the detection limit, only 5 ppm of chlorous acid was required. Furthermore, when an experiment was performed in the presence of artificial saliva, 500 ppm of sodium hypochlorite was needed to reduce the M. tuberculosis below the detection limit, but only 25 ppm of chlorous acid was needed. That data indicates that chlorous acid is a more powerful disinfectant than sodium hypochlorite, regardless of the presence or absence of artificial saliva. Therefore, chlorous acid may be used as a useful bactericidal agent to sterilize clinical environments contaminated with M. tuberculosis.

Virologic failure and HIV drug resistance have emerged with the widespread use of antiretroviral therapy (ART). An understanding of these predictors is the basis for prevention strategies to achieve a high treatment success rate. A retrospective cohort study was conducted among antiretroviral-naïve people living with HIV (PLWH) registered in the national AIDS program database of the National Health Security Office Region 4, Thailand, between January 2014 and December 2018. To determine the cumulative incidence rate of virologic failure and related factors, all PLWH were monitored for viral load status through December 2019. Virologic failure was defined as HIV viral load >1,000 copies/mL after 6 months of ART. Of the 42,229 PLWH identified, 10,211 PLWH with primary ART regimens and follow-up data were included. There were 67.1% males, and the mean age was 35 years (standard deviation: 11.6 years). During the median observation period of 0.88 years (interquartile range: 0.23–1.94 years) after ART initiation, 2.4% (242/10,211) of the PLWH experienced virologic failure. The Cox proportional hazard model revealed that the risk of developing virologic failure was significantly associated with age <30 years and baseline CD4 cell count ≤200 cells/mm³ . Active case finding, early ART initiation, and strengthening of the HIV continuum of care intervention are strongly recommended in order to minimize treatment failure.

Monkeypox is a zoonotic viral disease caused by monkeypox virus infection, which is endemic to Africa. Since May 2022, the disease has rapidly spread worldwide, and imported cases have been sporadically confirmed in China. Given these circumstances, data on confirmed cases were collected consecutively in Chengdu, Southwest China, to investigate their clinical and epidemiological characteristics. In this study, 28 male patients were confirmed to have monkeypox infection, with 26 men who had sex with men. Typical lesions included papules, pustular papules, vesicles, scabs, and ulcers. The most common sites of skin lesions were the anogenital and perineal areas, and three patients developed widespread exanthem. Seven patients reported a history of sexually transmitted diseases, none of whom was hospitalized, and there were no deaths. Three instances of secondary transmission were identified among close contacts, all of whom were the sexual partners of the participants. Furthermore, this observation provides insights into public health for the surveillance of this emerging disease and raises awareness among at-risk individuals.

Updating and evaluating facility-based guidance in cancer centers for managing healthcare personnel (HCP) in close contact with individuals with coronavirus disease 2019 (COVID-19) is challenging because these settings are typically excluded from general guidance and practical data on this population are limited. This study aimed to describe whether apparent outbreaks occurred under the updated protocol in the real-world setting of a cancer center. From July 2022 to January 2023, 402 HCP who were in close contact with an individual with COVID-19 were identified and divided into two groups: the separation group, which underwent a 5-day quarantine with physical isolation (172 HCP), and the cohabitation group, which underwent a 10-day quarantine (227 HCP). A nucleic acid amplification test (NAAT) was conducted the day before the HCP returned to work. Data from medical records were retrospectively collected and analyzed. As a primary outcome, no outbreaks due to post-quarantine transmission from HCP in close contact with individuals with COVID-19 were observed throughout the study period in either group. Our findings suggest that a 5-day quarantine for HCP in close contact with individuals with COVID-19 might be applicable in cancer center settings if combined with NAAT before returning to work, without increasing the risk of apparent outbreaks.

This report analyzes a measles outbreak that occurred at a medical institution (Hospital A) in Gyeonggi-do in April 2024, aiming to examine its epidemiological characteristics and derive implications for disease control policies. A cross-sectional study was conducted on 469 confirmed cases and contacts associated with Hospital A during the outbreak period using telephone interviews and on-site epidemiological investigations. A frequency analysis of epidemiological data was performed using statistical software. The attack rate related to the outbreak at Hospital A was 0.64%, with a secondary attack rate of 25.0%. The outbreak involved three confirmed measles cases, including one patient (index case) and two healthcare workers (secondary cases), all carrying the B3 genotype. In total, 469 individuals were exposed during the outbreak at Hospital A, including the three confirmed cases. The outbreak likely originated from a hospital visitor as the source of infection, with no additional transmission beyond hospital staff. To prevent transmission, prompt contact management, periodic antibody testing, and additional vaccinations for staff are recommended.

Recently, Staphylococcus argenteus, previously indistinguishable from Staphylococcus aureus, has been recognized as a clinically relevant microorganism because of mass spectrometry. However, despite its clinical significance, limited information is available on S. argenteus. This study evaluated the antimicrobial susceptibility and clinical phenotypes of S. argenteus isolated from clinical specimens. This single-center, retrospective study analyzed cases wherein S. argenteus was detected in clinical specimens obtained at Nagoya City University East Medical Center between April 2023 and April 2024. The organism was identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Patient data, including clinical outcomes, were collected and reviewed to classify cases as infections or colonization. S. argenteus was isolated from 23 specimens of 21 patients, with sputum being the most common source (78.3%). Sixty-seven percent of isolates were susceptible to penicillin; 95.2% to erythromycin; and 100% to oxacillin, clindamycin, sulfamethoxazole-trimethoprim, vancomycin, and teicoplanin. Thirteen cases of infection were recorded; pneumonia was the predominant diagnosis (11 cases) in these cases, followed by otitis externa and vertebral osteomyelitis. Most patients were successfully treated with antibiotics, and only one died of S. argenteus pneumonia.