ABSTRACT
INTRODUCTION: Since the first report of a novel coronavirus infection caused by SARS-CoV-2 in late 2019, the infection has spread rapidly and had a significant impact on our lives. In the early stages of the COVID-19 pandemic, there was no adequate testing system in place, despite an urgent need for infection control measures in student dormitories. METHODS: We have been monitoring SARS-CoV-2 in wastewater as part of our infection control efforts in the university facilities since fall 2020. In the four dormitories, absorbent cotton was placed in the drains that the facility wastewater passed through, and samples were collected twice a week and processed by RT-PCR for SARS-CoV-2. The dormitory residents were informed of the monitoring results the next morning. RESULTS: The positivity of residents in the dormitories was highly consistent with the positivity of wastewater. Wastewater was positive in 89% of cases before any residents were tested and found positive. Facility wastewater monitoring showed sensitivities of 80.4% and specificities of 87.6%. No traceable resident-to-resident transmission of infection within the facility was confirmed during the study period. CONCLUSION: Sampling a single wastewater outlet in a building for SARS-CoV-2 PCR can effectively indicate the presence or absence of COVID-19 cases and be very useful for infection control of a facility. This simple and effective monitoring is applicable to future outbreaks of both emerging and re-emerging infectious diseases.
ABSTRACT
The COVID-19 pandemic, caused by SARS-CoV-2, has had a significant worldwide impact, affecting millions of people. COVID-19 is characterized by a heterogenous clinical phenotype, potentially involving hyperinflammation and prolonged tissue damage, although the exact underlying mechanisms are yet to be fully understood. Sphingolipid metabolites, which govern cell survival and proliferation, have emerged as key players in inflammatory signaling and cytokine responses. Given the complex metabolic pathway of sphingolipids, this study aimed to understand their potential role in the pathogenesis of COVID-19. We conducted a comprehensive examination of sphingolipid modulations across groups classified based on disease severity, incorporating a time-course in serum and urine samples. Several sphingolipids, including sphingosine, lactosylceramide, and hexosylceramide, emerged as promising indicators of COVID-19 severity, as validated by correlation analyses conducted on both serum and urine samples. Other sphingolipids, such as sphingosine 1-phosphate, ceramides, and deoxy-dihydroceramides, decreased in both COVID-19 patients and individuals with non-COVID infectious diseases. This suggests that these sphingolipids are not specifically associated with COVID-19 but rather with pathological conditions caused by infectious diseases. Our analysis of urine samples revealed elevated levels of various sphingolipids, with changes dependent on disease severity, potentially highlighting the acute kidney injury associated with COVID-19. This study illuminates the intricate relationship between disturbed sphingolipid metabolism, COVID-19 severity, and clinical factors. These findings provide valuable insights into the broader landscape of inflammatory diseases.
Subject(s)
COVID-19 , SARS-CoV-2 , Severity of Illness Index , Sphingolipids , COVID-19/metabolism , COVID-19/blood , COVID-19/virology , Humans , Sphingolipids/metabolism , Sphingolipids/blood , Male , Female , Middle Aged , Adult , Sphingosine/analogs & derivatives , Sphingosine/metabolism , Aged , Biomarkers/blood , Biomarkers/metabolismABSTRACT
OBJECTIVE: The aim of this study is to characterise the molecular characteristics of NDM-producing Enterobacterales, which have been on the increase in recent years in Japan, where IMP-producing bacteria are dominant among carbapenemase-producing Enterobacterales. METHODS: We collected 21 strains of NDM-producing Enterobacterales detected between 2015 and 2022 at five hospitals in Tokyo and performed illumina whole genome sequencing. For the seven selected strains, nanopore long-read sequencing was also performed to characterise the plasmids harbouring blaNDM. RESULTS: Fourteen strains were Escherichia coli and all carried blaNDM-5. Among these strains, eight and three were sequence type (ST) 410 and ST167, respectively, and both groups of strains were spread clonally in different hospitals. Two strains of Klebsiella pneumoniae ST147 carrying blaNDM-1 were detected in a hospital, and these strains had also spread clonally. The remainder included Enterobacter hormaechei, Klebsiella quasipneumoniae, Citrobacter amalonaticus, and Klebsiella michiganensis. Plasmid analysis revealed that an identical IncX3 plasmid harbouring blaNDM-5 was shared among four strains of different bacterial species (E. coli, C. amalonaticus, K. michiganensis, and E. hormaechei) detected at the same hospital. In addition, a Klebsiella quasipneumoniae strain detected at a different hospital also carried an IncX3 plasmid with a similar genetic structure. CONCLUSIONS: Nosocomial spread of multiple multidrug-resistant global clones and transmission of IncX3 plasmids harbouring blaNDM-5 among multiple species were detected as the major pathways of spread of NDM-producing Enterobacterales in Tokyo. Early detection of carriers and measures to prevent nosocomial spread are important to prevent further spread of NDM-producing organisms.
ABSTRACT
A cholecystocutaneous fistula is a type of external biliary fistula that occurs when there is an abnormal connection between the gallbladder and skin. We report the first case of a cholecystocutaneous fistula that occurred in association with the development of lymphoma in the gallbladder. A 76-year-old woman who was under observation for follicular lymphoma with a low tumor burden presented with fatigue and abdominal pain. Imaging studies revealed cholecystitis associated with an abdominal subcutaneous abscess, and lymphoma transformation was confirmed by a lymph node biopsy. Edwardsiella tarda was cultured from both the abdominal subcutaneous abscess and percutaneous transhepatic gallbladder drainage, demonstrating cholecystocutaneous fistula, and open cholecystectomy revealed lymphoma cell infiltration into the gallbladder. Our case showed unique complications, and its successful management was associated with aggressive lymphoma development.
ABSTRACT
Background: Cryptococcosis is a notable infectious complication of liver transplantation. Currently, there is no recommendation for screening serum cryptococcal antigen (CrAg) levels in solid organ transplant recipients. We aimed to explore the role of serum CrAg in liver transplant recipients at an institution where posttransplant serum CrAg has been widely tested. Methods: This retrospective study was conducted at a tertiary care center in Japan. All liver transplant recipients with serum CrAg measured either for screening or for diagnostic testing at least once after transplantation between April 2005 and March 2022 were included. For participants with either a positive CrAg test result or positive culture for Cryptococcus, we manually reviewed clinical manifestations, management, and prognosis from the medical records. Results: During the study period, 12 885 serum CrAg tests (median, 16 tests per patient) were performed in 468 liver transplant recipients. The 1-year posttransplant incidence of positive serum CrAg test results and culture-proven cryptococcosis was 1.9% (9/468) and 0.6% (3/468), respectively. No patient with persistently negative serum CrAg test results showed growth of Cryptococcus in culture. Four patients had clinical manifestations consistent with cryptococcosis, of whom 2 (50.0%) started antifungal therapy promptly based on a positive serum CrAg test result. In contrast, 5 patients had no clinical manifestations. Three of the 5 (60.0%) patients did not receive antifungal therapy and remained free of clinical manifestations. Conclusions: Serum CrAg test was more sensitive than culture among liver transplant recipients and prompted early diagnosis and antifungal therapy in symptomatic patients. However, serial screening of serum CrAg in asymptomatic patients may be of little value, with the potential for false-positive results.
ABSTRACT
Missense mutations in certain small envelope proteins diminish the efficacy of antibodies. Consequently, tracking the incidence and types of vaccine-escape mutations (VEMs) was crucial both before and after the introduction of universal hepatitis B vaccination in Japan in 2016. In this study, we isolated hepatitis B virus (HBV) DNA from 58 of 169 hepatitis B surface antigen (HBsAg)-positive blood samples from Japanese blood donors and determined the nucleotide sequence encoding the small envelope protein. DNA from six (10%) of the samples had VEMs, but no missense mutations, such as G145R, were detected. Complete HBV genome sequences were obtained from 29 of the 58 samples; the viral genotype was A1 in one (3%), A2 in three (10%), B1 in nine (31%), B2 in five (17%), B4 in one (3%), and C2 in 10 (34%) samples. Tenofovir-resistance mutations were detected in two (7%) samples. In addition, several core promoter mutations, such as 1762A>T and 1764G>A, and a precore nonsense mutation, 1986G>A, which are risk factors for HBV-related chronic liver disease, were detected. These findings provide a baseline for future research and highlight the importance of ongoing monitoring of VEMs and drug resistance mutations in HBV DNA from HBsAg-positive blood donors without HBV antibodies.
Subject(s)
Hepatitis B, Chronic , Hepatitis B , Humans , Hepatitis B virus/genetics , Hepatitis B Surface Antigens/genetics , Japan , Blood Donors , DNA, Viral/genetics , Mutation , GenotypeABSTRACT
AIM: Hepatitis A (HA) is a vaccine-preventable disease. In regions with good sanitation, men who have sex with men (MSM) are the key affected populations. During the 2018-2019 HA outbreak among MSM in Japan, we actively vaccinated MSM living with HIV (MSM-LWHIV) with Aimmugen. As previously reported, their antibody seroconversion rate due to vaccination was lower than that of healthy individuals. However, the durability of Aimmugen in people living with HIV has not yet been reported. We evaluated attenuation after the one-series vaccination (comprising three inoculations) and the factors associated with attenuation. METHODS: We retrospectively examined anti-HA immunoglobulin G (anti-HA-IgG) titers and other clinical data from our hospital's medical records. Patients with no history of vaccination or HA infection (i.e., negative HA-IgG titers) who received one series of Aimmugen, achieved seropositivity, and anti-HA-IgG antibodies were tested ≥2 years after three doses were included. Fisher's exact test and the Mann-Whitney U-test were performed. p < 0.05 was considered statistically significant. RESULTS: Fifty-one MSM-LWHIV were included. All were seropositive after the third dose with a median HA-IgG titer of 10.1 (interquartile range, 7.2-12.2) (sample/cut-off values [s/co]). In 45 (40-49) months, seropositivity decreased to 90% (46/51) and was attenuated to a median of 4.4 (2.3-6.5) s/co. Lower baseline B cell counts (p = 0.049), lower anti-HA-IgG levels after the second dose (p = 0.002), and lower anti-HA-IgG levels after the third dose (p = 0.003) were associated with seronegativity. CONCLUSIONS: Anti-HA-IgG titers of vaccinated MSM-LWHIV may be attenuated; thus, additional immunizations should be considered.
ABSTRACT
BACKGROUND: Among solid organ transplant (SOT) recipients, heart transplant (HT) recipients are at a higher risk of Toxoplasma gondii infection. As Toxoplasma seroprevalence varies by geographic location, updated local epidemiology is essential to guide preventive and therapeutic strategies. However, the Toxoplasma seroprevalence and incidence of post-transplant toxoplasmosis among SOT recipients in Japan are unknown. METHODS: We performed a single-center retrospective observational study at an HT center in Tokyo, Japan. All HT recipients aged ≥18 years between 2006 and April 2019 were included. We reviewed patient charts and conducted a questionnaire survey to investigate the risk factors for infection. RESULTS: Among 105 recipients included in the study, 11 (10.5%) were seropositive before transplant. Ninety-five recipients (90.5%), including all pre-transplant seropositive recipients, answered the questionnaire. The recipients who had lived in Okinawa (odds ratio [OR] 7.5 [95% CI 1.42-39.61]; P = .032) and who reported raw-meat eating habits (OR 4.64 [95% CI 1.04-23.3]; P = .021) were more likely to be seropositive. None of the patients developed symptoms of toxoplasmosis. The post-transplant incidence of other major adverse outcomes was not significantly different according to the pre-transplant serostatus. CONCLUSIONS: About 10% of HT recipients at an HT center in Tokyo were seropositive for Toxoplasma pre-transplant, and none developed symptomatic toxoplasmosis post-transplant on trimethoprim-sulfamethoxazole. The history of raw meat consumption was associated with seropositivity; therefore, avoiding it might be recommended for HT recipient candidates.
Subject(s)
Heart Transplantation , Toxoplasma , Toxoplasmosis , Adolescent , Adult , Humans , Heart Transplantation/adverse effects , Incidence , Japan/epidemiology , Risk Factors , Seroepidemiologic Studies , Toxoplasmosis/diagnosis , Toxoplasmosis/epidemiology , Toxoplasmosis/etiology , Transplant Recipients , Retrospective StudiesABSTRACT
Bacillus cereus, which causes opportunistic infections in hospitals as well as food poisoning, is genetically similar to Bacillus anthracis. We herein report the draft genome including the capsule operon of B. cereus BCER1 isolated from the blood of a hospital patient in Japan.
ABSTRACT
INTRODUCTION: Since the SARS-CoV-2 Omicron variant became dominant, assessing COVID-19 vaccine effectiveness (VE) against severe disease using hospitalization as an outcome became more challenging due to incidental infections via admission screening and variable admission criteria, resulting in a wide range of estimates. To address this, the World Health Organization (WHO) guidance recommends the use of outcomes that are more specific to severe pneumonia such as oxygen use and mechanical ventilation. METHODS: A case-control study was conducted in 24 hospitals in Japan for the Delta-dominant period (August-November 2021; "Delta") and early Omicron (BA.1/BA.2)-dominant period (January-June 2022; "Omicron"). Detailed chart review/interviews were conducted in January-May 2023. VE was measured using various outcomes including disease requiring oxygen therapy, disease requiring invasive mechanical ventilation (IMV), death, outcome restricting to "true" severe COVID-19 (where oxygen requirement is due to COVID-19 rather than another condition(s)), and progression from oxygen use to IMV or death among COVID-19 patients. RESULTS: The analysis included 2125 individuals with respiratory failure (1608 cases [75.7%]; 99.2% of vaccinees received mRNA vaccines). During Delta, 2 doses provided high protection for up to 6 months (oxygen requirement: 95.2% [95% CI:88.7-98.0%] [restricted to "true" severe COVID-19: 95.5% {89.3-98.1%}]; IMV: 99.6% [97.3-99.9%]; fatal: 98.6% [92.3-99.7%]). During Omicron, 3 doses provided high protection for up to 6 months (oxygen requirement: 85.5% [68.8-93.3%] ["true" severe COVID-19: 88.1% {73.6-94.7%}]; IMV: 97.9% [85.9-99.7%]; fatal: 99.6% [95.2-99.97]). There was a trend towards higher VE for more severe and specific outcomes. CONCLUSION: Multiple outcomes pointed towards high protection of 2 doses during Delta and 3 doses during Omicron. These results demonstrate the importance of using severe and specific outcomes to accurately measure VE against severe COVID-19, as recommended in WHO guidance in settings of intense transmission as seen during Omicron.
Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , COVID-19/prevention & control , Oxygen/therapeutic use , Japan/epidemiology , Respiration, Artificial , Case-Control Studies , Vaccine Efficacy , SARS-CoV-2ABSTRACT
AIM: Differential patterns of peripheral memory T cell subsets in nonalcoholic fatty liver disease (NAFLD) were assessed using flow cytometry (FCM) to elucidate their association with NAFLD severity and provide a new noninvasive method to sensitively detect the disease severity in addition to existing biomarkers. METHODS: We assessed the differential frequencies of peripheral memory T cell subsets in 103 patients with NAFLD according to the degree of liver fibrosis (FIB) using FCM analysis. We focused on the following populations: CCR7+ CD45RA+ naïve T, CCR7+ CD45RA- central memory T cells (TCM), CCR7- CD45RA- effector memory T, and CCR7- CD45RA+ terminally differentiated effector memory T (TEMRA) cells in CD4+ and CD8+ T, Th1, Th2, and Th17 cells, respectively. To evaluate the pathological progression of the disease, these frequencies were also examined according to the degree of the NAFLD activity score (NAS). RESULTS: Several significant correlations were observed between laboratory parameters and peripheral memory T lymphocyte frequencies according to the degree of liver FIB and NAS in NAFLD. In univariate and multivariate analyses, the frequency of CD8+ TEMRA cells predicted severe FIB, and the predictive power was validated in an independent cohort. Furthermore, the frequencies of several memory T cell subsets sensitively indicated the pathological progression of NAFLD (Th17 TCM: steatosis, CD4+ TCM: lobular inflammation, and CD8+ TEMRA and effector memory T cells: hepatocellular ballooning). CONCLUSIONS: Our results suggest that the analysis of peripheral memory T lymphocyte frequencies can noninvasively predict severe FIB and sensitively indicate the pathological progression of NAFLD.
ABSTRACT
People living with HIV (PLWH) have a higher prevalence of psychiatric disorders than the general population. We retrospectively examined the medical records of PLWH who underwent the Kessler Psychological Distress Scale-10, the Patient Health Questionnaire-9, and the Generalized Anxiety Disorder-7 at an HIV referral hospital during the COVID-19 pandemic. Some PLWH who were unemployed with a history of psychiatric visits may remain in poor mental health during the prolonged COVID-19 pandemic until the Omicron variant occurs, so they may need to pay attention to their mental health.