American Veterinary Medical Association

Abstract Background Aztreonam-avibactam (ATM-AVI) is a β-lactam/β-lactamase inhibitor combination to treat infections caused by Gram-negative organisms, particularly those carrying metallo-β-lactamases (MBLs) and other β-lactamases. Aztreonam is stable to hydrolysis by MBLs and avibactam inhibits Class A, C, and some Class D enzymes. We examined ATM-AVI activity against Enterobacterales isolates that were either positive for the Class A carbapenemase KPC or resistant to ceftazidime-avibactam among isolates collected as a part of the ATLAS global surveillance program (2019-2023). Methods 88,189 isolates from 226 medical centers in 56 countries (excluding mainland China, Canada, and the USA) were collected and tested for susceptibility using the broth microdilution method according to CLSI guidelines. Analysis was performed with CLSI 2025 breakpoints. Isolates testing with meropenem MIC values >1 µg/mL or Escherichia coli, Klebsiella pneumoniae, K. oxytoca, or Proteus mirabilis isolates testing with ceftazidime and/or aztreonam MIC values >2 µg/mL were screened for β-lactamase genes by PCR. Results Of the 88,189 isolates characterized, 2039 screened positive for KPC and 3837 were resistant to ceftazidime-avibactam. Against these, ATM-AVI in vitro activity was (genotype/phenotype, percent susceptible, MIC90): All, 99.6%, 0.25 µg/mL; KPC-positive, 99.8%, 0.5 µg/mL; ceftazidime-avibactam-resistant 95.3%, 2 µg/mL (Table 1). No comparator agents were active against this many isolates in any group. Of isolates carrying KPC, ≥98% were susceptible to ATM-AVI, while CAZ-AVI activity was 91% (KPC-2), 94% (KPC-3), and 42% (other KPC), noting that some of these isolates co-carried MBLs (Figure 1). Conclusion Aztreonam-avibactam demonstrated potent in vitro activity against isolates that carry KPC carbapenemases and those that are ceftazidime-avibactam-resistant. While some uncommon variants of KPC can confer resistance to ceftazidime-avibactam, aztreonam-avibactam retained potency against these in vitro. Disclosures Katherine Perez, PhD, Pfizer: Stocks/Bonds (Public Company)

Abstract Background Antimicrobial resistance among GN pathogens is a serious global public health issue, affecting adult and pediatric populations. New treatment options for carbapenem-resistant or ESBL-producing pathogens are needed. Methods This study was a Phase 2/3, open-label, randomized, active-controlled, multinational clinical study enrolling children (birth to < 18 years old) with confirmed or suspected hospital-acquired/ventilator-associated bacterial pneumonia, complicated intra-abdominal infection, or complicated urinary tract infection including pyelonephritis. Participants required hospitalization and intravenous antibacterial therapy and were randomized 3:1 to IMI/REL or active control. Bacterial pathogens isolated from primary infection sites were sent to a central laboratory (IHMA; Schaumburg, IL, USA) for testing by broth microdilution of IMI/REL using CLSI guidelines. Molecular mechanisms of resistance to IMI and/or IMI/REL were characterized; PFGE typing was used to determine relatedness of isolates. Susceptibility and molecular characterization of isolates were compared to surveillance data from SMART, a global surveillance study monitoring pathogen prevalence and resistance of GN bacteria. Results Of 115 participants randomized, 90 were in the microbiological modified intent-to-treat population (mMITT) population. MIC distributions from clinical trial and surveillance isolates were similar (Fig 1-4). IMI nonsusceptible (NS) baseline pathogens (7 Enterobacterales (non-Morganellaceae) (N=4) and P. aerguinosa (N=3)) from the mMITT population were evaluated for resistance determinants against β-lactams using PCR and sequencing. Of the 4 IMI NS Enterobacterales isolates evaluated, 3 were susceptible (S) to IMI/REL, (the isolates carrying KPC, AmpC, or no acquired β-lactamase were S), the isolate carrying NDM-1 was NS. Of the 3 IMI NS Psa isolates evaluated, 1 was S to IMI/REL, with 1 isolate carrying PDC-374 being S, and the isolate carrying the VEB-9 ESBL and 1 of the isolates carrying PDC-374 being NS. Conclusion Isolates from this clinical trial were generally susceptible to IMI/REL with low MICs and representative of pediatric surveillance isolates. Disclosures Katherine Young, M.S., Merck & Co., Inc.: Stocks/Bonds (Public Company) David W. Hilbert, PhD, Merck & Co., Inc.: Stocks/Bonds (Public Company) Carmelle Norice, MD, Merck & Co., Inc.: Stocks/Bonds (Public Company) Prachi Nair, BS, Merck & Co., Inc.: Stocks/Bonds (Private Company) Christopher Bruno, MD, Merck & Co., Inc.: Stocks/Bonds (Public Company)

Veterinarians, animal owners, and the animal food industry share responsibility to properly dispose of euthanized animals and prevent pentobarbital from entering the animal food sup­ply. To better understand current veterinary practices regard­ing disposal of animals following pentobarbital euthanasia so that targeted outreach could be developed, the FDA Center for Veterinary Medicine (CVM) and the American Veterinary Medi­cal Association (AVMA) conducted a survey of AVMA members on euthanasia and subsequent disposal practices. This presen­tation will focus on the results of the survey as they apply to disposal of cattle and small ruminants and resulting planned outreach efforts.

Following the onset of COVID-19, demand for US veterinary services rapidly increased, similarly driving up demand in upstream veterinary labor markets. This increasing demand starkly contrasted with the "excess capacity" period following the Great Recession, marked by fewer opportunities and low wages for veterinarians. Better models and forecasts of veterinary labor market conditions improve information for decision-making by veterinarians, relevant business owners, professional associations, and educational institutions. Well-performing approaches will adapt to new data as they become available and avoid the assumption that short-term market dynamics will persist permanently. In this paper, we modify an approach often used to identify the forecasting model best suited to the data. Then, using the best forecasting model, we generate forecasts and prediction intervals around them to meet the available data and realities of veterinary labor markets to 2035. This approach removes subjectivity, accommodates model refinements, and acknowledges that the future is unknown. We find that the supply and demand indicators for veterinary services both indicate continued growth. We do not find statistically significant or consistent differences in either supply or demand growth, which would be consistent with a competitive market for veterinary services and labor. The data do not support an expectation of a continued shortage in the US veterinarian labor markets, as suggested in previous studies. We identify several areas where improved data resources and further methodological advancements could shed more light on the economic conditions facing veterinarians.

Tokenism, unfortunately, is often synonymous with a superficial form of inclusion, lacking genuine authenticity. It can be likened to a false flag, conveniently blaming the tokenized individual if a program fails. Beyond maintaining a mere appearance of diversity, tokenism has detrimental effects, particularly on those from underrepresented demographics, and may also harm the overall organization. More significantly, tokenism falls short of addressing diversity and inclusion issues; instead, it actively exploits individuals. This exploitation can result in severe well-being consequences, inducing stress, imposter syndrome, and the recently described high-functioning anxiety syndrome. The accompanying sense of isolation and the pressure to constantly excel can ultimately lead to depression, burnout, or even the voluntary or involuntary withdrawal of the individual from the program, causing lasting negative impacts on both the individual and the broader initiative.

To identify demographic and employment variables associated with an associate veterinarian's intent to remain at their organization in the next 5 years and to assess the impact of positive leadership in the practice and on veterinarians' well-being. 2,037 associate veterinarians in private practice who participated in the 2021 and 2022 AVMA Census of Veterinarians surveys. Associate veterinarian demographic and employment information was used in regression analysis to determine the likelihood of remaining employed at their organization in the next 5 years and the impact leadership has on an associate veterinarian's employment. Higher levels of burnout, living in an urban community, and working in corporate practice were associated with lower odds of remaining in the next 5 years. Associates who worked in a practice in which they believed their leaders practiced positive leadership had higher odds of remaining in the next 5 years. An increase in a practice's leadership index was associated with a likelihood to remain employed over the next 5 years. Decreases in the leadership index were associated with higher burnout levels among associates, more work experience, working more hours, and specialty/referral practices. Findings supported anecdotal evidence that lack of positive leadership in a private practice may lead to higher odds of retention issues in a practice, as well as lower job satisfaction, organizational commitment, and workplace well-being among associates. Positive leadership practices might provide protective factors to critical veterinary business outcomes like team member retention and engagement.

To estimate the effects of practice ownership on wellbeing of US private practice veterinarians. 1,217 practice owners and 1,414 associate veterinarians (ie, nonowners) who participated in the 2021 AVMA Census of Veterinarians and Practice Owners Survey. A professional quality of life instrument was used to measure compassion satisfaction (CS; a positive attribute), burnout (BO), and secondary traumatic stress (STS) in practice owners and nonowners both as scores and as score categories (low, moderate, and high CS, BO, and STS). For hypothesis tests, propensity score matching was used, with owners (n = 595) matched to nonowners (595) on several demographic and employment factors. Owners had significantly (P < .001) higher CS scores (mean ± SE, 34.1 ± 0.3) and lower BO scores (26.1 ± 0.3) than nonowners (32.8 ± 0.3 and 26.9 ± 0.3, respectively), but STS scores were comparable between groups (27.4 ± 0.3 and 27.5 ± 0.3; P = .55). The prevalence of low CS scores and high BO scores was significantly (P < .001) higher for nonowners versus owners (53.8% vs 42.7% and 51.6% vs 46.4%, respectively). Both owners and nonowners had a high prevalence of high STS scores (81.8% and 83.2%, respectively; P = .53). Results suggested that practice ownership confers a benefit to private practice veterinarians in terms of CS and BO, but not STS. The prevalence of poor CS, BO, and STS scores was higher than reported previously for 2016 to 2018, suggesting an impact of the COVID-19 pandemic. The high prevalence of high STS scores in both groups warrants attention and action to protect the welfare of the veterinary workforce and support optimal patient care.

腸原性囊胞に罹患した47～65日齢の肉用出荷鶏11例を病理学的に検索した．全囊胞が単房性で脾臓に密着していた．9例が単一，他2例が各2囊胞を有していた．囊胞は長径が15～68mmで，内腔に淡明粘液を満たしていた．組織学的に，囊胞壁は被覆上皮，上皮下結合組織，平滑筋及び線維性被膜の4層により構成され，被覆上皮は単層の立方または円柱上皮より成り，しばしば絨毛状突起を形成していた．同突起を被う円柱上皮細胞は，遊離側に過ヨウ素酸シッフ及びアルシアンブルーpH2.5の両染色で陽性並びにアザン染色で青染する粘液顆粒を満たしていた．得られた成績から各囊胞が腸に類似する粘膜により内張りされていることが示唆された．1例の囊胞上皮に巣状の重層扁平化生，各2例の囊胞に出血または化膿性炎が観察された．

Harmful algal blooms can have deleterious effects on animal and human health as well as the environment and are anticipated to become more frequent and intensified in the future because of climate change. Veterinarians are well positioned to diagnose and treat animals affected by HABs and to educate livestock owners and the public about health risks and environmental issues associated with those toxic events. Pets, livestock, wildlife, and marine life can all be affected by HABs. Information about HABs is becoming increasingly assessable as a result of ongoing research into the structure, properties, toxic mechanisms, and geographic distribution of toxins found in HABs. The AVMA's multi-entity working group on HABs is comprised of members from the Aquatic Veterinary Medicine Committee, Committee on Environmental Issues, and Council on Public Health and is working to make more information and resources regarding HABs available to practicing veterinarians. The present article is the first of those resources and provides a review of HABs, with a focus on livestock. It includes background material about bloom formation, appearance, and persistence as well as descriptions of clinical observations from early field cases and more recent information about the causative organisms and toxins to provide livestock veterinarians a foundation for understanding HABs. Reporting of HABs and prevention and mitigation strategies for livestock owners are also discussed.