In recent years, the concept of one-health approach has been emphasized, and the spread of drug-resistant bacteria from animals and the environment has become an issue.

Escherichia coli producing extended-spectrum β-lactamases (ESBLs), bla_CTX-M-15-producing B2-O25-ST131, a global high-risk-clone strain, has been reported in various species.

Herein, 20 ESBLs-producing E. coli strains were isolated from gut contents of aquatic environmental organisms, which are rarely studied as target organisms, for resistance gene and molecular epidemiological analyses.

All 20 strains tested were classified as phylogenetic group D and harbored bla_CTX-M. A total of 13 (65%) strains were bla_CTX-M-15, followed by 6 (30%) bla_CTX-M-14 and 1 (5%) bla_CTX-M-161.

Molecular epidemiological analysis using the POT method identified 13 strains harboring bla_CTX-M-15, which are the two clonal types D-0166-nonST131 and D-08-nonST131.

ESBLs-producing E. coli may have originated from environmental organisms different from the high-risk clone strains frequently detected worldwide.

From the one-health approach viewpoint, the trend of such resistant bacteria must be observed from environmental organisms and clinical perspectives.

Considering the need to promote appropriate antibiotic use, an action plan was developed to address the problem of drug-resistant bacteria. Despite the support for appropriate antibiotic use in inpatient management, support for pharmacist-led interventions is limited in dental/oral surgery. Therefore, we aimed to clarify the effects of pharmacist-led interventions among outpatients in dental and oral surgery departments who were prescribed amoxicillin hydrate (AMPC) and cefditoren pivoxil (CDTR-PI) from October 2018 to September 2020 (preintervention group) and October 2020 to September 2022 (postintervention group), respectively, and were enrolled as study participants. We compared the average antimicrobial use density (AUD) between the preintervention and postintervention groups (AMPC: 22.2 vs. 62.7; CDTR-PI: 139.3 vs. 82.3, respectively), revealing a significant difference in CDTR-PI (p < 0.05). Despite no significant increase in the average AUD for AMPC with pharmacist-led prescription support, the use of third-generation cephalosporins significantly decreased. Thus, a pharmacist-led intervention can promote appropriate antibiotic use in outpatient settings per the current guidelines.

Nontuberculous mycobacteria (NTM) inhabit common water environments such as water pipes and bathrooms. The risk of developing pulmonary NTM disease is associated with the inhalation of these bacteria. NTM are resistant to chlorine-based disinfectants because such disinfectants exhibit corrosive effects when in contact for extended periods, presenting challenges for disinfecting these bacteria in the environment. Ionless^® hypochlorous acid water (purified hypochlorous acid water) CLFine^® (CLFine) is a slightly acidic chlorine-based disinfectant that reduces corrosiveness; the bactericidal effect of this agent against NTM was investigated. Free-floating Mycobacterium avium at 10⁵ CFU/well became undetectable with hypochlorous acid sodium and CLFine within 30 minutes at 40 ppm, whereas both agents required 60 minutes for Mycobacterium abscessus complex. The evaluation of the evaporation effect in a dish showed a reduction in the bacterial count of approximately 50% after 1 hour of exposure to 40 ppm CLFine for both bacterial species; however, this reduction was not achieved even after 3 hours of exposure using 300 ppm CLFine in aerosol spraying for both bacterial species. Thus, CLFine sterilizes NTM on environmental surfaces when applied through immersion. However, expecting a sterilization effect when applied through space spraying is difficult, highlighting the challenges of sterilizing NTM in the environment.