Enrollment begins January 2026.
Controlled Human Infection Model: Influenza
Full title: A double-blinded, Phase 1 clinical trial to establish an RG-A/Texas/71/2017 (H3N2) influenza Controlled Human Infection Model (CHIM) that safely and reproducibly induces symptomatic influenza virus infection in healthy adults 18 – 45 years of age after intranasal challenge.
What is the purpose of this study?
Influenza, also known as the flu, is a contagious illness that affects the respiratory system (lungs and throat). Each year, it causes millions of people to miss school or work and puts extra pressure on hospitals and healthcare providers.
The flu virus can change and spread quickly. To better respond to new strains or stop future pandemics, we first need to know more about how the flu infects people and how the body fights back.
One way to study the flu very closely is with a Controlled Human Infection Model (CHIM). These studies expose healthy adult volunteers to a virus (like influenza) or a bacteria (like pertussis) in a safe and controlled setting.
This study will help to create a model, or a specific way of doing research, that will help future flu vaccines to be tested quickly while keeping the highest quality of research standards.
To learn more about CHIMs, also sometimes called challenge studies, take a look at our blog series. In this series, we explain what CHIM and challenge studies are, how and why they are done, and how we keep participants safe and comfortable during their stay.
About Influenza
Most people who get influenza (the flu) only feel mildly ill. However, for some, especially those under 6 and over 65, the flu can be severe.
Flu symptoms usually start 1 to 4 days after exposure to the virus and usually include fever, cough, and muscle aches. Other common symptoms include chills, tiredness, headache, sore throat, loss of appetite, and a runny or stuffy nose.
The best way to prevent or stop the spread of the flu is to get vaccinated. Unlike some vaccines, which are only given once, flu vaccines need to be given yearly. The National Advisory Committee on Immunization (NACI) recommends that all people in Canada aged 6 months and older get a seasonal flu vaccine.
Sources: Flu (influenza): For health professionals - Canada.ca
You may be able to take part if you are:
18-45 and in good health.
able and willing to stay in a private room at the IWK for up to 11 days.
Other criteria may exclude you from this study. A team member will go over these criteria during your first conversation.
Interested in participating? Here are a few things you should know:
You will be exposed to the flu virus under expert medical care and may become mildly ill.
You will spend an estimated 7 - 11 days and nights in a specialized hospital room.
Your vitals and samples will be collected daily during the hospital stay.
You will be cared for by experienced staff who are dedicated to supporting your comfort and wellness.
You are welcome to fill your free time as you choose between study tasks
Want to know more about what it’s like on the challenge unit? Check out our participant testimonials on the Participate, and Participant Wellness pages, along with our blog posts about challenge studies, controlled human infection models, and infectious diseases.
What will I have to do?
Enrollment begins January 2026.
Ready to sign up?
This study is funded by the Canadian Institutes of Health Research (CIHR)
Operating Grant: Clinical Trials Projects (RN#531438).
Project name: CTF2024-FluCHIM
IWK REB Project Number: 1031787