Background
The WHO Science for Health Department announces a online public consultation on the draft ‘Key Ethical Criteria for Controlled Human Infection Studies in Emergency Preparedness’ from 6 August to 6 September 2026.
This consultation is part of the work of the Foresight, Leadership & Ethics for Science Unit’s commitment to promoting ethical research. The ethics team within the Unit has previously produced the Key Criteria for the Ethical Acceptability of COVID-19 Human Challenge Studies (2020), the broader WHO Guidance on the Ethical Conduct of Controlled Human Infection Studies (2021), and Key Criteria for the ethical acceptability of controlled human infection studies during public health emergencies (2025).
Controlled human infection studies (CHIS) involve the intentional infection of research participants and have been used to study a range of infectious diseases. CHIS may contribute to preparedness for future public health emergencies, i.e., when conducted in advance of any declared emergency. The draft document circulated in this consultation sets out ethical criteria for CHIS conducted as part of emergency preparedness, including studies involving pathogens of pandemic potential but also those that might produce local or regional health emergencies.
Future emergencies may be caused by pathogens that are difficult to predict, including novel pathogens (“Disease X”) or new forms of known pathogens. The draft criteria are therefore intended to be pathogen-agnostic. The draft also addresses issues that are prominent in the preparedness context, among them uncertainty about the eventual benefits of such research, the selection of challenge strains, the development of new controlled human infection models, the location of studies and the distribution of international research capacity, and risks of transmission of infection from participants to third parties.
This guidance is intended to supplement existing mechanisms for ethical consideration and research ethics review of CHIS, rather than to replace them.
Objective of the consultation
The goal of this online, open public consultation is to gather feedback from stakeholders on the draft Key Ethical Criteria for Controlled Human Infection Studies in Emergency Preparedness.
General guidance on providing comments
Download and review the draft guidance. Compose your responses to each question using your preferred software and paste your responses into the online form.
Submissions cannot be made anonymously. You will be required to provide valid responses to questions that ask your full name, your organizational affiliation (if any), your role (job title), your country of residence, and your personal email address or your organizational email address (if submitting on behalf of an organization) in order to make a submission. Submissions that are not accompanied by valid responses to these questions may not be accepted for consideration.
By participating, you consent to providing your personal information and comments to WHO to contact you, if needed.
All comments will be carefully reviewed. We may share a summary of key points raised in the public consultation, along with the participants' demographics and their representation of stakeholder groups, without revealing any individual participant's information or affiliations, on the WHO website. We do not intend to publish the raw information from individual responses.
For any query related to the consultation, please contact: ct_ethics@who.int with the subject “CHIS preparedness consultation”.
Comments on the draft guidance must be submitted by 11:59 on Sunday, 6 September 2026, Central European Time (GMT/UTC +1).