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Research ethics in the COVID-19 pandemic
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The COVID-19 pandemic has had a devastating effect globally. Hundreds of millions of people have been infected with the SARS-CoV-2 virus and, according to the Economist Intelligence Unit, between 7 and 15 million people have died globally. The pandemic has highlighted difficult research ethics issues, including ethical issues in human challenge studies, cluster trials to evaluate public health measures, and reporting randomized controlled trials impacted by the pandemic. My research and public outreach explore each of these issues.


Human challenge studies. From the start of the pandemic, it was clear that a vaccine was urgently needed. But traditional vaccine development can take 10 to 15 years. Human challenge studies with the novel coronavirus were proposed to speed the development of a vaccine and save lives. But are such studies justifiable in terms of social value, risks to participants, and the potential impact on public trust in vaccines? In 2020, I was a member of a World Health Organization working group exploring the ethics of SARS-CoV-2 human challenge studies and our report, released on May 6, 2020, attracted international attention.


Cluster trials to evaluate public health measures. As cases of COVID-19 grew exponentially, people were locked down in their houses, non-essential businesses were closed, schools were shuttered, and travel was prohibited. While these precautionary measures were understandable, could rigorous evaluations of the de-implementation of these public health policies be ethically conducted. We explored the ethical issues in conducting a cluster randomized trial of school reopening, including the timing of the study, impact on vulnerable people, the role of gatekeepers, and the need for informed consent.


Reporting RCTs impacted by the pandemic. Thousands of clinical trials globally were terminated, paused or modified during the pandemic. These changes impact hundreds of thousands of trial participants and put the enrollment of millions on hold. But how should trials impacted by the pandemic be reported? I was part of an international team writing reporting guidelines (CONSERVE 2021) for trials modified by the COVID-19 pandemic and other extenuating circumstances.


Audio/ video

Prêts à se faire infecter par la COVID-19 pour mettre au point un vaccine. Radio Canada. April 26, 2020.


Looking at the ethics of human challenge studies for COVID-19 vaccine. London Live with Mike Stubbs. June 3, 2020.


Would you take part in a vaccine trial? CBC Radio Halifax. June 15, 2020.


How can pharma build trust in COVID-19 vaccines? Kitchener Today with Brian Bourke, 570 News. November 25, 2020.


How can pharma build trust in COVID-19 vaccines? Here and Now, CBC Radio. November 26, 2020


How can pharma build trust in COVID-19 vaccines? The Morning News on 770 CHQR, Calgary. November 26, 2020.


How can pharma build trust in COVID-19 vaccines? CTV News London. November 27, 2020.


Ethik-dumping: Koloniales denken in der wissenschaft. Wissenschaft im Brennpunkt, Deutschlandfunk (Germany). December 27, 2020.


Global pandemic highlighted social inequalities. CTV News. December 28, 2020.


Top 10 of 2020: COVID-19 pandemic. CTV National News. January 1, 2021.


How do we decide when students should return to in-person classes? Let’s Talk London with Jess, AM980 News. January 21, 2021.


Should Canadians be able to choose which COVID-19 vaccine they receive? The Morning News on 770 CHQR, Calgary. January 27, 2021.


Local students heading back to class as COVID-19 case counts tick down. Let’s Talk London with Jess, AM980 News. February 1, 2021.


AstraZeneca and J&J COVID-19 vaccines in Canada. CTV Morning News. March 6, 2021.


Would you risk your life to save others from a deadly virus? Bloomberg News (USA). April 16, 2021.




Shortcuts in clinical trials may cause more harm than good. Medical Ethics Advisor. May 1, 2020.


COVID-19: Why is the race to a vaccine taking so long? May 6, 2020.


Exploring the ethics of human challenge studies for COVID-19. Schulich School of Medicine and Dentistry. May 22, 2020.

Should we deliberately infect healthy volunteers with COVID-19? Wired (United Kingdom). May 23, 2020.


Western scholar contributes to WHO human trial guidelines. Western News. May 27, 2020.


Thousands worldwide volunteer for deliberate coronavirus exposure to speed up vaccine development. Global News. June 3, 2020.


Volunteers sign up to put their lives on the line for a coronavirus vaccine. The Washington Post (USA). June 15, 2020.


Some volunteers want to be infected with coronavirus to help find a vaccine. But it isn’t that simple. (USA). August 6, 2020.


Ethical dilemmas raised in rushing a vaccine. 570 News, Kitchener. August 28, 2020.


Challenge trials face too many ethical and logistical hurdles to go forward, experts say. The Hill Times. September 14, 2020.


A line in the sand. Rapport Magazine. October 5, 2020.


COVID-19: Vaccine trials need more transparency to enable scrutiny and earn public trust, say experts. British Medical Journal (United Kingdom). October 22, 2020.


EMA will assess potential COVID-19 vaccine on ‘case by case’ basis. PMLiVE. November 5, 2020.


Proof of vaccination wades into 'murky territory' ethically, experts say. Global News. December 9, 2020.


Why the COVID-19 vaccines may feel different from other routine shots. Vox (USA). December 17, 2020.


Can radical transparency overcome resistance to COVID-19 vaccines? LeapsMag (USA). December 17, 2020.


Coronavirus vaccine: understanding trial results, roll-out and what happens next – an expert guide. Australian Times. December 19, 2020.


I’m in the Pfizer trial. Should I get vaccinated early? Medium (USA). January 21, 2021.


More evidence needed to inform policy on sending kids back to school. Western News. January 21, 2021.


Here's what medical experts say about the importance of kids returning to school. CTV News. January 21, 2021.


Study needed to determine COVID-19 risks of keeping schools open: researcher. London Free Press. January 22, 2021.


When should kids return to in-person learning? Western University researcher, colleagues finding answers. Global News. January 23, 2021.


Will Canadians get to choose which COVID-19 vaccine they get? Global News. January 26, 2021.


Even with vaccine, don’t expect mask-wearing and social distancing to disappear. January 27, 2021.


The UK is infecting people with COVID-19 for science. Is it worth it? WIRED (United Kingdom). February 18, 2021.


What are human challenge studies? Medical News Today. February 18, 2021.


让健康人“以身试毒”?全球首个新冠病毒“人体挑战试验”引争议. Southern Weekly Newspaper (China). February 21, 2021.


¿El nacionalismo de vacunas acabará con los esfuerzos para contener COVID-19? Publimetro (Mexico). February 21, 2021.


英新冠“人体挑战试验”首席研究员答澎湃:如何确保安全伦理.The Paper (China). February 23, 2021.


What are COVID “human challenge” trials, and are they ethical? The Paper Gown (USA). February 24, 2021.


Efficacy figures of COVID-19 vaccines don't tell the whole story: experts. Airdrie Today. March 4, 2021.


Covid trial infecting healthy volunteers needs full transparency, say campaigners. The Guardian (United Kingdom). March 18, 2021.


Vaccinations: Getting the shot is a moral obligation for everyone who can, says bioethicist. Daily Oil Bulletin. April 5, 2021.


Worksite clinics: Experts consider how employers can encourage staff to get vaccinated. Daily Oil Bulletin. April 6, 2021.


Considering ethical, legal and practical implications of mandatory vaccinations. Daily Oil Bulletin. April 7, 2021.

COVID-19 vaccine trials for children are ongoing. How do they differ from adults? Global News. July 20, 2021.



World Health Organization. Key criteria for the ethical acceptability of COVID-19 human challenge studies. Geneva: WHO, 2020. [19 pages] (Member of the Working Group for Guidance on Human Challenge Studies for COVID-19)



McPartlin SO, Morrison J, Rohrig A, Weijer C. COVID-19 vaccines: Should we allow human challenge studies to infect healthy volunteers with SARS-CoV-2? British Medical Journal 2020; 371: m4258.


Jamrozik E, Littler K, Bull S, Emerson C, Kang G, Kapulu M, Rey E, Saenz C, Shah S, Smith PG, Upshur R, Weijer C, Selgelid MJ; WHO Working Group for Guidance on Human Challenge Studies in COVID-19. Key criteria for the ethical acceptability of COVID-19 human challenge studies: Report of a WHO Working Group. Vaccine. 2021; 39(4): 633-640.


Weijer C, Hemming K, Phillips Hey S, Fernandez Lynch H. Reopening schools safely in the face of COVID-19: Can cluster randomized trials help? Clinical Trials 2021;18(3) :371-376.


Orkin AM, Gill PJ, Ghersi D, Campbell L, Sugarman J, Emsley R, Steg PG, Weijer C, Simes J, Rombey T, Williams HC, Wittes J, Moher D, Richards DP, Kasamon Y, Getz K, Hopewell S, Dickersin K, Wu T, Ayala AP, Schulz KF, Calleja S, Boutron I, Ross JS, Golub RM, Khan KM, Mulrow C, Siegfried N, Heber J, Lee N, Kearney PR, Wanyenze RK, Hróbjartsson A, Williams R, Bhandari N, Jüni P, Chan AW; CONSERVE Group. Guidelines for Reporting Trial Protocols and Completed Trials Modified Due to the COVID-19 Pandemic and Other Extenuating Circumstances: The CONSERVE 2021 Statement. JAMA 2021 Jun 21. doi: 10.1001/jama.2021.9941.

Nix, H.P., Weijer, C. Uses of equipoise in discussions of the ethics of randomized controlled trials of COVID-19 therapies. BMC Medical Ethics 2021; 22: 143.

Public outreach

Peterson A, Owen AM, Weijer C. Is it ethical to forcibly withdraw ventilators from nursing home patients for reallocation to COVID-19 patients? JME Blog. April 27, 2020.


Weijer C. Ethics must not be ignored when testing COVID-19 vaccines. The Conversation. August 24, 2020.


Weijer C. Human challenge studies to speed development of a COVID-19 vaccine are unethical. The Hill Times (Ottawa). September 14, 2020.


Weijer C. How clinical trials test COVID-19 vaccines. The Conversation. September 21, 2020.


Weijer C. How pharma can build trust in COVID-19 vaccines: transparency on trials and side effects. The Conversation. November 23, 2020.


Nix HP, Weijer C. Close Eneph? SARS-CoV-2 challenge studies and altruistic kidney donation. JME Blog. December 8, 2020.


Peterson A, Weijer C, Largent EA. COVID-19 vaccines are worthless if people aren’t vaccinated. The Hill (Washington, DC). December 12, 2020.


Nix HP, Weijer C. Dialyzing the discourse: a response to Rohrig and Manheim. JME Blog. February 10, 2021.


Weijer C. SARS-CoV-2 human challenge studies should not be permitted. Cato Unbound. March 15, 2021.


Morrison J, Weijer C. Publish the protocol for the UK SARS-CoV-2 human challenge study now. BMJ Opinion. March 23, 2021.

Weijer C. Pfizer’s COVID-19 vaccine now has full FDA approval. Here’s what that means for unvaccinated people, organizations and pharma. The Conversation. August 26, 2021.


Health of nations: from mass lockdowns to mass vaccinations? Panelists: Francois Balloux, Jonathon Kitson, Charles Weijer. Adam Smith Institute. United Kingdom. December 1, 2020.


Debate: "Should we allow healthy volunteers to be infected with SARS-CoV-2 in challenge studies to develop a vaccine?" Yes – Josh Morrison. No – Charles Weijer. University College London. December 8, 2020.

Ethical issues conducting research in the COVID-19 pandemic. Canadian Donation and Transplantation Research Program. April 26, 2021.


Ethics and future of human challenge trials with SARS-CoV-2 to speed vaccine development. Panelists: Meta Roestenberg, Alastair Fraser-Urquhart, Seema Shah, Charles Weijer, Gagandeep Kang. Society for Clinical Trials. May 17, 2021.

Global health research ethics in the COVID-19 pandemic. Das Global Health Wochenende. Germany. May 29, 2021.

The ethics of SARS-CoV-2 human challenge studies. Ethics Seminar. European Research Council. Belgium. June 22, 2021.

The ethics of SARS-CoV-2 human challenge studies. Grand Rounds. Department of Medicine, Western University. London, Canada. October 1, 2021.

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