The threat from antimicrobial resistance (AMR) continues to grow. Japan’s National Action Plan on Antimicrobial Resistance, which was formulated in 2016 and targets six areas, has already had a major impact on the countermeasures implemented against AMR. Particular advances have been made in AMR-related surveillance, and we now know the situation regarding antimicrobial use and antimicrobial-resistant bacteria in the country. Educational and awareness-raising activities for medical professionals and the general public have been actively implemented and seem to have contributed to a gradual move toward an appropriate use of antimicrobials. However, there is still insufficient understanding of the issue among the general public. Determining how to use surveillance results and implementing further awareness-raising activities are crucial to address this. Tasks for the future include both raising awareness and the promotion of AMR research and development and international cooperation. The government’s next Action Plan, which will detail future countermeasures against AMR based on the outcomes of and tasks identified in the current Action Plan, has been delayed due to the COVID-19 pandemic and is urgently awaited.

Background: Both physicians and patients are proactive towards managing seasonal influenza in Japan and six drugs are approved. Although many countries have national influenza surveillance systems, data on nationwide prescription practices of anti-influenza drugs are lacking. Therefore, we aimed to clarify the status of anti-influenza drug use in Japan by analyzing real-world data. Methods: This retrospective study analyzed open data from the National Database of Health Insurance Claims and Specific Health Checkups, which covers most claims data from national health insurance. We estimated the annual number of patients prescribed anti-influenza drugs, which drugs they were prescribed, the patients’ age and sex distribution, drug costs, and regional disparities for the period 2014–2020. Results: For 2014–2019, an estimated 6.7–13.4 million patients per year were prescribed anti-influenza drugs, with an annual cost of 22.3–48.0 billion JPY (Japanese Yen). In addition, 21.1–32.0 million rapid antigen tests were performed at a cost of 30.1–47.1 billion JPY. In 2017, laninamivir was the most frequently prescribed anti-influenza drug (48%), followed by oseltamivir (36%), while in 2018, the newly introduced baloxavir accounted for 40.8% of prescriptions. After the emergence of COVID-19, the estimated number of patients prescribed anti-influenza drugs in 2020 dropped to just 14,000. In 2018, 37.6% of prescriptions were for patients aged < 20 years compared with 12.2% for those aged ≥ 65 years. Prescriptions for inpatients accounted for 1.1%, and the proportion of prescriptions for inpatients increased with age, with men were more likely than women to be prescribed anti-influenza drugs while hospitalized. Conclusions: Based on our clarification of how influenza is clinically managed in Japan, future work should evaluate the clinical and economic aspects of proactively prescribing anti-influenza drugs.

Invasive Group G streptococcal infection (iGGS) has increasingly been recognized as a cause of severe disease, mainly among elderly people with chronic illnesses. This study aimed to examine age-related differences in clinical characteristics of iGGS and describe its characteristics among very elderly individuals (≥80 years). Fifty-four iGGS patients for whom detailed clinical information was available were identified from 2002 to 2014 in a tertiary care hospital in Japan. iGGS (n = 54) was compared with invasive Group A (iGAS; n = 17) and B streptococcal infection patients (iGBS; n = 52) based on patient age. The incidence of iGGS in our catchment area significantly increased during the study period. The prevalence of iGGS in the very elderly population was higher than that of iGAS or iGBS (p<0.001). Among iGGS patients, cardiovascular disease, chronic kidney disease, oxygen demand, and bacteremia with unknown focus of infection were more frequent in the very elderly population (p = 0.009, p = 0.02, p = 0.04, and p = 0.04, respectively). Altered mental status was present in half of iGGS patients aged ≥60 years (p = 0.03). In contrast, alcohol drinking and liver cirrhosis were significantly more frequent in patients with iGGS aged <60 years than in other age groups (p<0.001, p = 0.001, respectively). Levofloxacin resistance in GBS isolates was significantly more frequent among very elderly patients than among other age groups (p<0.001). The burden of iGGS has been increasing in our catchment area. Different iGGS-associated clinical characteristics were found in each age group. Unclear and atypical clinical manifestations and syndromes were likely to be observed in very elderly patients. Alcohol drinking and liver cirrhosis may contribute to iGGS even in patients aged <60 years. Understanding these age-related differences could be helpful for optimal diagnosis and treatment.

Antimicrobial resistance is a major global concern and economic threat, necessitating a reliable monitoring approach to understand its frequency and spread via the environment. Hospital wastewater serves as a critical reservoir for antimicrobial-resistant organisms; however, its role in resistance gene distribution and dissemination remains poorly understood. This study integrates metagenomic and metatranscriptomic analyses, elucidating the dynamics of antimicrobial resistance in hospital wastewater. Integrated metagenomic and metatranscriptomic sequencing were used to identify actively expressed antimicrobial-resistant genes and antimicrobial-resistant bacteria, offering comprehensive insights into antimicrobial resistance dynamics in hospital wastewater. Liquid chromatography–tandem mass spectrometry analysis revealed the presence of ampicillin, sulbactam, levofloxacin, sulfamethoxazole, and trimethoprim in the sample, which could apply selective pressure on antimicrobial resistance gene expression. While multidrug resistance genes were the most prevalent sequences in both metagenome-assembled genomes and plasmids, plasmid-derived sequences showed a high mRNA/DNA ratio, emphasizing the presence of functionally expressed antimicrobial resistance genes on plasmids rather than on chromosomes. The metagenomic and metatranscriptomic analyses revealed Serratia nevei MAG14 with high mRNA levels of antimicrobial resistance genes; moreover, multidrug-resistant Serratia sp., genetically related to MAG14, was isolated from the wastewater, supporting the phenotypic characterization of crucial antimicrobial-resistant bacteria and validating the genome analysis results. The findings underscore key genes and bacteria as targets for antimicrobial resistance surveillance in hospital wastewater to protect public and environmental health.

Background: In 2017, the Japanese government published an evidence‐based manual describing the appropriate use of antibiotics in outpatient settings to tackle the problem of antimicrobial resistance. To fill the evidence‐practice gap, we developed a clinician‐targeted course aimed at improving clinician skills in the daily clinical practice of treating acute respiratory tract infections (RTIs) based on the manual. The aim of this study was to evaluate the efficacy of the course.Methods: This course consisted of lectures using illness scripts and checklists, as well as interactive communication skills training using role‐playing. We performed a vignette‐based evaluation of the changes in the knowledge and attitudes of the course participants toward prescribing antibiotics for nonpneumonia RTIs, using pre‐ and postcourse questionnaires. The questionnaires also included course feedback via the use of a 5‐point Likert scale.Results: Thirty‐eight clinicians were included in the analyses, and 90% of these participants had graduated ≥20 years ago. We found statistically significant reductions in the intention to prescribe antibiotics for four of the six nonpneumonia RTI vignettes: acute bronchitis (−47.2%; 95% confidence interval [CI] −66.3 to −28.1%), common cold (−16.2%; 95% CI −30.8 to −1.6%), acute pharyngitis (−27.0%; 95% CI −49.0 to −5.0%), and acute rhinosinusitis (−33.3%; 95% CI −53.3 to −13.3%). The course seemed to be satisfactory for experienced doctors who were the relevant target population of such a workshop.Conclusions: The refresher course was helpful for reducing the participants’ intensions to prescribe antibiotics for nonpneumonia RTIs.

Antimicrobial resistance (AMR) has reached a critical situation globally, prompting urgent national responses to this escalating crisis, including the prioritization of novel antibiotic research. In 2016, Japan initiated a national AMR action plan that promoted appropriate antibiotic use in the country and encouraged a national environment conducive to mitigation measures. However, tackling AMR remains difficult. From an epidemiological perspective, this challenge now extends beyond severe infections, impacting common community-acquired infections, including uncomplicated urinary tract infections (uUTls) and gonorrhea. In uUTIs, the rising prevalence of extended-spectrum β-lactamase-producing and fluoroquinolone-resistant Escherichia coli diminishes the effectiveness of current, routinely used oral antibiotics, necessitating an exploration into innovative solutions. Similarly, the growing resistance of Neisseria gonorrhoeae to antibiotics such as azithromycin raises concerns about the efficacy of current therapeutic options for gonorrhea, which is a highly prevalent sexually transmitted infection. In Japan, since the removal of azithromycin as the recommended first-line treatment, there are no oral first-line antibiotics available to treat gonorrhea. Therefore, novel oral antibiotics are urgently needed for both serious and commonly occurring community-acquired infections. This narrative review discusses the limited availability of novel antibiotics in Japan, the distinctive features of the Japanese antibiotic repertoire and AMR epidemiology, and potential alternative oral treatments for community-acquired infections, including uUTIs and gonorrhea. Japan has been making significant advances toward tackling the AMR crisis through an updated national action plan, AMR policy changes, and innovative approaches to developing novel antibiotics. Substantial international cooperation and the engagement of diverse industry sectors are essential to address the pressing issue of AMR.