
Communicable E58: Reducing hospital-acquired pneumonia – the HAPPEN trial and how it happened
CommunicableShow Notes
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 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). 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. 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/
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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 Johnson, et al. Vancomycin Taper and Pulse or Fidaxomicin for Recurrent C. difficile Infection. NEJM Evid. DOI: 10.1056/EVIDoa2600016 Bundgaard, et al. Response-Tailored or Standard-Duration Antibiotic Treatment for Infective Endocarditis (POET II). NEJM. DOI: 10.1056/NEJMoa2607887 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 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 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 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.
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