Communicable

In this episode of Communicable, Emily McDonald returns for another ‘Quarterly catch-up’ and is joined by Angela Huttner as co-host. Together, they review four recent randomised clinical trials, focusing on antibiotic treatment duration and different treatment approaches across a range of infections and patient populations [1–4]. They discuss the results and weigh in on their implications for clinical practice.

References

1. Johnson, et al. Vancomycin Taper and Pulse or Fidaxomicin for Recurrent C. difficile Infection. NEJM Evid. DOI: 10.1056/EVIDoa2600016
2. Bundgaard, et al. Response-Tailored or Standard-Duration Antibiotic Treatment for Infective Endocarditis (POET II). NEJM. DOI: 10.1056/NEJMoa2607887 
3. Bielicki, et al. Oral step-down, optimal drug, and total duration of antibiotic treatment in African children hospitalised with severe community-acquired pneumonia (PediCAP): a factorial randomised controlled trial. Lancet 2026. DOI: 10.1016/S0140-6736(26)00879-2
4. Carlsen, et al. Individualized Duration of Antibiotic Treatment in Culture-Negative Early-Onset Sepsis in Late Preterm and Term-Born Neonates in Denmark: A Multicenter, Open-Label, Randomised, Controlled Non-Inferiority Trial. Lancet Child Adolesc Health. DOI: 10.1016/S2352-4642(26)00118-5

In this episode of Communicable, hosts Emily McDonald and Marc Bonten are joined by Sylvain Lother and Valentijn Schweitzer for a discussion on the use of macrolides in community-acquired pneumonia. Together, they examine the evidence for adding a macrolide to beta-lactam therapy, which patients may benefit from combination treatment, and how available evidence can inform clinical practice.

Resources: 

• AMMI Canada, https://ammi.ca/en/home/

Further reading

• Postma DF, et al. Antibiotic Treatment Strategies for Community-Acquired Pneumonia in Adults (CAP-START). NEJM 2015. DOI: 10.1056/NEJMoa1406330 
• Qian ET, et al. Cefepime vs Piperacillin-Tazobactam in Adults Hospitalized With Acute Infection: the ACORN Randomized Clinical Trial. JAMA 2023. DOI: 10.1001/jama.2023.20583 
• Schweitzer VA, et al.  Narrow-spectrum antibiotics for community-acquired pneumonia in Dutch adults (CAP-PACT): a cross-sectional, stepped-wedge, cluster-randomised, non-inferiority, antimicrobial stewardship intervention trial. Lancet Infect Dis 2022. DOI: 10.1016/S1473-3099(21)00255-3
• van Daalen FV, et al. Management of community-acquired pneumonia in adults: Practice Guideline from The Dutch Working Party on Antibiotic Policy and Dutch Association of Chest Physicians. CMI Comms 2026. DOI: 10.1016/j.cmicom.2026.105206

At the Critical Care Reviews meeting in Belfast in June this year, REMAP-CAP investigators presented results suggesting that oseltamivir may be harmful in critically ill patients with influenza, upending a long-standing clinical practice in intensive care [1]. In this fourth collaboration between SIDP’s Breakpoints and ESCMID’s Communicable podcasts, hosts Erin McCreary and Josh Davis are joined by Steve Webb (Monash University), senior REMAP-CAP investigator and 'godfather of adaptive trial design', and Steve Tong (University of Melbourne), esteemed clinical trialist and friend of both podcasts. Together, they walk through the trial domain’s design, outcomes and results, also highlighting how these findings demonstrate the importance and clinical impact of randomised clinical trials.

At the time of this episode recording in August, the results discussed were available as a preprint version [1]. 

Resources

• REMAP-CAP: A Randomised, Embedded, Multi-factorial, Adaptive Platform Trial for Community-Acquired Pneumonia, https://www.remapcap.org/ 

References

1. Murthy S, et al. Oseltamivir for Critically Ill Patients with Influenza: A Randomised Trial. Lancet 2026. Preprint http://dx.doi.org/10.2139/ssrn.7172531

In this episode of Communicable, Emily McDonald and Josh Davis host Henning Bundgaard and Sami El-Dalati for a discussion on early oral antibiotic switch for endocarditis, focusing on the POET trial, led by Bundgaard, and its clinical impact seven years after the results were first published in 2019 [1]. The episode also covers the ‘prose’ and cons of early oral switch therapy, as well as broader challenges of implementing new evidence in practice when it goes against long-standing dogma.

References

1. Iversen K, et al. Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis, NEJM 2018. DOI: 10.1056/NEJMoa1808312

Further reading:

• Pries-Heje MM, et al. Five-Year Outcomes of the Partial Oral Treatment of Endocarditis (POET) Trial, NEJM 2022. DOI: 10.1056/NEJMc2114046
• El-Dalati S, et al. Partial Oral Versus Intravenous Antibiotic Therapy for Endocarditis With Management by a Multidisciplinary Team: A Retrospective Cohort Study, OFID 2025. DOI: 10.1093/ofid/ofaf625
• McDonald EM, et al. Guidelines for Diagnosis and Management of Infective Endocarditis in Adults: A WikiGuidelines Group Consensus Statement, JAMA Netw Open 2023. DOI: 10.1001/jamanetworkopen.2023.26366
• European Society of Cardiology (ESC). 2023 ESC Guidelines for the management of endocarditis, 2023.

In this episode of Communicable, Amy Legg (Brisbane, Australia), Rekha Pai Mangalore (Melbourne, Australia) & Angela Huttner (Geneva, Switzerland) return for the third part of the ‘We will make you love PK/PD’ series. The hosts are joined by two experts, Amanda Gwee (Melbourne, Australia) & Sebastian Wicha (Hamburg, Germany), to dive into an important application of PK/PD: model-informed precision dosing (MIPD), and how it allows for more informed, individualised dosing decisions. The episode also covers the open-access educational tools, KidsCalc and TDMx, developed by Gwee and Wicha respectively, and the steps clinicians can take to put MIPD into practice, keeping the individual patient at the centre of dosing decisions.

Resources 

• TDMx, https://www.tdmx.eu/
• KidsCalc, https://www.kidscalc.org/

Further reading

• Broeker A, et al. Towards precision dosing of vancomycin: a systematic evaluation of pharmacometric models for Bayesian forecasting. CMI 2019. DOI: 10.1016/j.cmi.2019.02.029
• Brusamarello C, et al. How important are MIC determination methods when targeting vancomycin levels in patients with Staphylococcus aureus infections? J Antimicrob Chemother 2021. DOI: 10.1093/jac/dkab065
• De Cock PA, et al. Bedside model-informed precision dosing of vancomycin in severely ill neonates and children in Belgium (the BENEFICIAL trial): a multicentre, randomised controlled trial. Lancet Child Adolesc Health 2026. DOI: 10.1016/S2352-4642(25)00385-2  
• Gwee A, et al. Identifying a therapeutic target for vancomycin against staphylococci in young infants. J Antimicrob Chemother 2022. DOI: 10.1093/jac/dkab469
• Haiping X, et al. Model-informed precision dosing of vancomycin in children 3 months to 18 years of age using Australia-wide data. Antimicrob Agents Chemother 2026. DOI: 10.1128/aac.01840-25  
• Harwood K, et al. Refining Absolute GFR Estimation in Children: Development and Validation of the GROW-GFR Equation. Front Pharmacol 2026. 
• Minichmayr IK, et al. Model-informed precision dosing: State of the art and future perspectives. Adv Drug Deliv Rev 2024. DOI: 10.1016/j.addr.2024.115421
• Starp J, et al. Towards model-informed precision dosing of intravenous linezolid: a multicentre external evaluation of pharmacokinetic models in critically ill adults. CMI 2026. DOI: 10.1016/j.cmi.2025.08.032
• Wilkins AL, et al. Individualized vancomycin dosing in infants: prospective evaluation of an online dose calculator. Int J Antimicrob Agents 2023. DOI: 10.1016/j.ijantimicag.2023.106728 
• US National Kidney Foundation for different equations for kidney function estimates as related to drug dosing – estimating kidney function for medication related decisions: Frequently Asked Questions | National Kidney Foundation

In the second edition of 'Quarterly catch-up', CMI Communications editors Emily McDonald and Erin McCreary round-up the biggest news in infectious diseases and review clinical microbiology and infectious diseases studies published in the second quarter of 2026 [1-4]. From Pneumocystis jirovecii pneumonia in solid-organ-transplant recipients to a double-blind randomised controlled trial reporting a new antibiotic for complicated urinary tract infections, Erin and Emily highlight four articles they found particularly noteworthy, and comment on whether the results can and should change clinical practice. 

References

1. Alanio A, et al. Pneumocystis jirovecii pneumonia in solid organ transplant recipients: a prospective observational cohort study, J Infect 2026. DOI: 10.1016/j.jinf.2026.106794
2. Ramendra R, et al. Procalcitonin to guide 7 versus 14 days of antibiotics in bloodstream infections: a secondary analysis of the BALANCE trial, JAMA Netw Open 2026. DOI: 10.1001/jamanetworkopen.2026.20973
3. Pai MP, et al. Challenging weight-tiered antibiotic prophylaxis in obese patients undergoing colorectal surgery using CT-derived body composition, CID 2026. DOI: 10.1093/cid/ciag383 
4. Takahashi S, et al. Efficacy and safety of cefepime–nacubactam and aztreonam–nacubactam compared with imipenem–cilastatin for complicated urinary tract infection or acute uncomplicated pyelonephritis (Integral-1): a double-blind, randomised phase 3 trial. Lancet 2026. DOI: 10.1016/S0140-6736(26)00596-9

Further reading

• The SNAP Trial Group. Cefazolin for Methicillin-Susceptible Staphylococcus aureus Bacteremia. NEJM 2026. DOI: 10.1056/NEJMoa2506905
• The SNAP Trial Group. Benzylpenicillin versus flucloxacillin or cloxacillin for the treatment of penicillin-susceptible Staphylococcus aureus bacteraemia (SNAP): an international, multicentre, open-label, non-inferiority randomised controlled trial. Lancet 2026. DOI: 10.1016/S0140-6736(26)00761-0
• McCreary EK, et al. Communicable episode 26: SNAP out of it – rethinking anti-staphylococcal penicillins for S. aureus bacteremia, the SNAP trial PSSA/MSSA results. Communicable Podcast 2025. https://share.transistor.fm/s/2a3c3bb4  
• Ilges D, et al. Anticalcitonin: limited utility of a context-dependent biomarker demonstrated in another real-world data set, CID 2026. DOI: https://doi.org/10.1093/cid/ciag396 
• Spellberg B. Procalcitonin–An enigmatic anxiolytic biomarker, JAMA Netw Open 2026. DOI: 10.1001/jamanetworkopen.2026.20978 

In this episode of Communicable, Nav Narayanan and Thomas Tängdén kick off the first 'Ask me anything' episode, inviting EUCAST and CLSI leadership Sören Gatermann, Christian Giske and Amy Mathers to answer questions from our listeners. Together, they discuss the roles and operations of both organisations, similarities and differences between EUCAST and CLSI, how breakpoints and guidance documents are developed, set the record straight about the 'I' category, explain which data inform breakpoint decisions, and much more.

This episode was edited by Communicable's executive producer, Angela Huttner.

Further reading

Documents/resources:

• CLSI MicroFree, https://em100.edaptivedocs.net/Login.aspx?ru=1
• EUCAST: When there are no antifungal breakpoints
• EUCAST: When there are no breakpoints?
• Use_of_fosfomycin_iv_breakpoints_General_advice_20240528.pdf
• EUCAST: Definition of S, I and R
• EUCAST Guidance Document, “When there are no breakpoints”, https://www.eucast.org/bacteria/guidance-documents/
• EUCAST Guidance Document for “Rare Yeasts”, https://www.eucast.org/fungi-afst/guidance-documents/

Articles (alphabetical): 

• Bixby ML, et al. Fosfomycin Disk Diffusion Testing among Klebsiella pneumoniae Results in Frequent Inner Colonies and Categorical Disagreement Based on Conflicting Breakpoint Organization Recommendations. Microbiol Spectr 2023. DOI: 10.1128/spectrum.03363-22
• DeMarco MG, et al. Impact of media brand on cefiderocol disk diffusion results. J Clin Microbiol 2025. DOI: 10.1128/jcm.01648-24
• Giske CG, et al. Aminoglycoside breakpoints-the EUCAST approach and what this means for the clinician. CMI 2025. DOI: 10.1016/j.cmi.2025.08.015
• Mouton JW, et al. MIC-based dose adjustment: facts and fables. J Antimicrob Chemother 2018. DOI: 10.1093/jac/dkx427
• Narayanan N, et al. Amoxicillin-Clavulanate Breakpoints Against Enterobacterales: Rationale for Revision by the CLSI. Clin Infect Dis 2024. DOI: 10.1093/cid/ciae201
• Narayanan N, et al. Amoxicillin-Clavulanate Breakpoints Against Enterobacterales: Rationale for Revision by the Clinical and Laboratory Standards Institute. Clin Infect Dis 2024. DOI: 
• Pham Thanh D, et al. A novel ciprofloxacin-resistant subclade of H58 Salmonella Typhi is associated with fluoroquinolone treatment failure. eLife 2016. DOI: 10.7554/eLife.14003.001 
• Smekal A. Swedish multicentre study of target attainments with β-lactams in the ICU: which MIC parameter should be used? J Antimicrob Chemother 2023. DOI: 10.1093/jac/dkad327
• Turnidge J, et al. How to: the application and analysis of categorical agreement in antimicrobial susceptibility testing using EUCAST breakpoints. CMI 2026. DOI: 10.1016/j.cmi.2025.12.018
• Turnidge J, et al. Rationale for contemporary antimicrobial treatment of Stenotrophomonas maltophilia: a narrative review. CMI Comms 2025. DOI: 10.1016/j.cmicom.2025.105082
• Weinstein M, et al. The CLSI Subcommittee on Antimicrobial Susceptibility Testing: Background, Organization, Functions, and Processes. J Clin Microbiol 2020. DOI: 10.1128/jcm.01864-19

In this episode of Communicable, Angela Huttner and Josh Davis are joined by Brett Mitchell, Aline Wolfensberger and Lauren Clack to discuss the HAPPEN trial to prevent hospital-acquired pneumonia led by Mitchell--and the important studies leading up to it [1-3]. The episode also explores trial designs used in their research that are both creative and practical, such as stepped-wedge and implementation trials, and how these approaches can bridge the gap between research and real-world practice.

References

1. Mitchell B, “The hospital acquired pneumonia prevention (HAPPEN) study: a multi-centre randomised controlled trial” in ESCMID Global 2026. https://online.escmid.org/media-6348-hospital-and-ventilator-associated-pneumonia-new-insights-on-prevention-diagnosis-and-treatment (Presentation).
2. White NM, et al. Effectiveness of oral care for the prevention of non-ventilator hospital-acquired pneumonia (HAPPEN): a multicentre, stepped-wedge, cluster-randomised trial in Australia. Lancet Infect Dis 2026. DOI: 10.1016/S1473-3099(26)00235-5.
3. Wolfensberger A, et al. Prevention of non-ventilator-associated hospital-acquired pneumonia in Switzerland: a type 2 hybrid effectiveness–implementation trial. Lancet Infect Dis 2023. DOI: 10.1016/S1473-3099(22)00812-X.

Further reading

• HAPPEN study website: Study overview and resources www.happenstudy.com
• Cassini A, et al. Burden of Six Healthcare-Associated Infections on European Population Health: Estimating Incidence-Based Disability-Adjusted Life Years through a Population Prevalence-Based Modelling Study. PLoS Med 2016. DOI:  10.1371/journal.pmed.1002150. 
• Pronovost P, et al. An Intervention to Decrease Catheter-Related Bloodstream Infections in the ICU. NEJM. DOI: 10.1056/NEJMoa061115. 
• Bion J, et al. ‘Matching Michigan’: a 2-year stepped interventional programme to minimise central venous catheter-blood stream infections in intensive care units in England. BMJ Quality & Safety 2013. DOI: 10.1136/bmjqs-2012-001325.
• Dixon-Woods M, et al. Explaining Matching Michigan: an ethnographic study of a patient safety program. Implementation Sci 2013. DOI: 10.1186/1748-5908-8-70.  
• Clack L, et al. Hybrid effectiveness-implementation studies in infection prevention and infectious diseases: a narrative review. CMI 2025. DOI: 10.1016/j.cmi.2025.10.022.
• Hospital Acquired Pneumonia Prevention (HAPPEN) Study: Statistical Analysis Plan
  https://www.medrxiv.org/content/10.1101/2025.08.14.25333719v1
• Oral care practices and hospital-acquired pneumonia prevention: A national survey of Australian nurses
  https://pubmed.ncbi.nlm.nih.gov/38724299/
• Nurses' experiences of providing oral care to hospitalised patients: A qualitative study
  https://pubmed.ncbi.nlm.nih.gov/40450434/

In this episode of Communicable, Thomas Tängdén and Rekha Pai Mangalore return for part 2 of the ‘We will make you love PK/PD’ series. In this round, they are joined by Iris Minichmayr (Austria) and Phil Selby (Australia) for a deep dive into how PK/PD data and principles can be used as integral clinical tools to support dosing decisions. They break down technical concepts of pharmacometrics such as population PK models, Monte Carlo simulations, probability of target attainment (PTA), and cumulative fraction of response (CFR), helping to make these approaches more accessible to everyday clinical practice.

This episode was edited by Kathryn Hostettler. The executive producer of Communicable is Angela Huttner.

Further reading

• Tängdén T, et al. Personalised patient management and infection prevention: current evidence and future perspectives. In: ESCMID Global 2025. Available on ESCMID Media: https://media.escmid.org/videos/01K7HWCJAHZ464H3XXK97SZ842

In this episode of Communicable, Emily McDonald and Josh Davis are joined by Roger Lewis (USA) and Ian Marschner (Australia) to compare and contrast Bayesian and frequentist statistical approaches. The panel discusses the fundamental principles of both methods, common misconceptions, and the extent to which they are often more similar than many realise. Together, they explore their use in clinical trial design, analysis, and reporting, including adaptive trials and sequential learning. Additional topics include sample size misconceptions, regulatory versus clinical thresholds, and the challenges of interpreting post hoc reanalyses of negative trials.

This episode was edited by Kathryn Hostettler and the executive producer of Communicable is Angela Huttner. 
 

Further reading:

• Berry SM, et al. Bayesian Adaptive Methods for Clinical Trials (Chapman & Hall/CRC Biostatistics Series). Boca Raton (FL): CRC Press; 2010. 
• FDA Guidance Document: Use of Bayesian Methodology in Clinical Trials of Drug and Biological Products FDA, 2026, https://www.fda.gov/regulatory-information/search-fda-guidance-documents/use-bayesian-methodology-clinical-trials-drug-and-biological-products
• Lee TC, et al. Contextualizing the use of corticosteroids in severe Pneumocystis jirovecii pneumonia through a Bayesian lens. CMI Comms 2025, https://www.cmi-comms.org/article/S2950-5909(25)00082-4/fulltext
• Livingston EH and Lewis RJ. JAMA Guide to Statistics and Methods, https://jamaevidence.mhmedical.com/Book.aspx?bookId=2742
• Marschner I. Confidence distributions for treatment effects in clinical trials: Posteriors without priors. Stat Med 2024, doi: 10.1002/sim.10000.
• Whitehead J. The design and analysis of sequential clinical trials. Revised 2nd ed. Chichester: John Wiley & Sons; 1997.