The HAPPEN Study
Hospital Acquired Pneumonia Prevention:
A randomised controlled trial
Healthcare associated infections (HAIs) are a significant threat in healthcare. In Australia, we have estimated 155,000 patients contract a HAI annually – one in ten patients today have an infection acquired in hospital.
Why this study is important?
The HAPPEN Study tested a simple oral-care program with 8,870 patients across three Australian hospitals. The program included providing toothbrushes and toothpaste, teaching patients and staff about tooth-brushing, helping patients who needed support, and giving feedback to hospital wards. It increased the number of patients cleaning their teeth from 16% to 62% and reduced the risk of non-ventilator hospital-acquired pneumonia by 60%.
Our study will:
The study phases
Our study consists of three phases, summarised below.

Where is the study up to?
Subscribe to receive more News on this study (below) and also check out the study News and progress page for the latest.
Right now, Phase 2 – has just been completed. We anticipate results from Phase 2 being available shortly.
We are also currently evaluating the resources we used and will update these during the second half of 2026. All our resources will then be made available open-source on this website, in the resources section.
Keep up to date
Subscribe to receive email News about the HAPPEN study. Don’t worry, these will be infrequent, but will keep you updated on key developments. Enter your email below.
We also have a very popular podcast on infection control, called Infection Control Matters, with 180K+ listens from over 130 countries. You can find it on your favourite podcast provider.
