Dalla Lana School of Public Health

"Post-hoc bias can play tricks on patients that can eventually lead to serious disappointments – and for health-care workers, it can ultimately lead to shortfalls in care"

People tend to continue with unproven treatments even if there’s no evidence to suggest an initial marginal improvement in symptoms is anything more than a potential coincidence, a new study has found.

"I've noticed many of my patients take unnecessary vitamins, pills or alternative remedies with little evidence to inform their choice, leading to a lot of distraction, wishful thinking and wasted money,” says senior study author Donald Redelmeier, a staff internist and senior scientist at Sunnybrook Health Sciences Centre, and professor in the department of medicine in the ��ɫֱ��’s Temerty Faculty of Medicine.

“Perhaps even more concerning is a false belief that leads to a missed diagnosis that later becomes incurable.”

The study, published in the journal JAMA Network Open, explores “post-hoc bias” – a tendency in reasoning that causes many patients to continue taking dubious or unreliable treatments. The bias encourages a popular misconception: that because one action preceded another later event, the first must have caused the second since it occurred in sequence.

But medical science, the researchers note, stresses that the order of two events does not prove a cause-and-effect since coincidences are frequent. The implication for medical care is that a patient who improved after a treatment is not necessarily a patient who improved because of the treatment.

Instead, other potential explanations include withdrawal from an adverse activity, added rest or the body’s own healing powers.

To test bias across a variety of clinical cases, the researchers ran multiple experiments using hypothetical clinical scenarios administered by a randomized survey of pharmacists and members of the community.

The scenarios described a patient with fatigue or another vague symptom who feels a bit better after trying a vitamin, shampoo, sugar pill or other treatment.

“We found that most respondents suggested continuing the treatment indefinitely even though the change in symptoms might be pure random chance," says Redelmeier, who is also affiliated ICES and the Institute for Health Policy, Management and Evaluation in ��ɫֱ��’s Dalla Lana School of Public Health.

"The post-hoc bias can play tricks on patients that can eventually lead to serious disappointments – and for health-care workers, it can ultimately lead to shortfalls in care."

While attributing an initial improvement in – or lack of – symptoms to a treatment is a quick and intuitive approach, the researchers say the study reinforces the need for both patients and clinicians to be cautious when drawing conclusions.

“An awareness of post-hoc bias will not make it disappear, however we suggest patients and clinicians need to think twice and stay mindful of alternative explanations.”

The study was supported by the Alfred P. Sloan Foundation, a Canada Research Chair in Medical Decision Sciences, Canadian Institutes of Health Research, the PSI Foundation of Ontario and the National Science Foundation.

This story was originally posted at Sunnybrook Research Institute

Sexual and Gender Minority Health Research, Centre for

laurie.bulchak — Sat, 27 Jul 2024 21:17:11 +0000

Sexual and Gender Minority Health Research, Centre for laurie.bulchak Sat, 07/27/2024 - 17:17

URL

https://www.dlsph.utoronto.ca/centre-for-sexual-and-gender-minority-health-research/

Vaccine Preventable Diseases, Centre for (CVPD)

laurie.bulchak — Sat, 27 Jul 2024 21:11:25 +0000

Vaccine Preventable Diseases, Centre for (CVPD) laurie.bulchak Sat, 07/27/2024 - 17:11

URL

https://www.dlsph.utoronto.ca/institutes/centre-for-vaccine-preventable-diseases/

Occupational Disease Prevention, Centre for

laurie.bulchak — Sat, 27 Jul 2024 21:09:59 +0000

Occupational Disease Prevention, Centre for laurie.bulchak Sat, 07/27/2024 - 17:09

URL

https://www.dlsph.utoronto.ca/institute/centre-for-occupational-disease-prevention/

Pandemics, Institute for

laurie.bulchak — Sat, 27 Jul 2024 17:02:47 +0000

Pandemics, Institute for laurie.bulchak Sat, 07/27/2024 - 13:02

URL

https://pandemics.utoronto.ca

��ɫֱ�� community members recognized with Order of Canada

bresgead — Thu, 04 Jul 2024 16:49:13 +0000

��ɫֱ�� community members recognized with Order of Canada

bresgead Thu, 07/04/2024 - 12:49

Cutline

(photo by Sgt Johanie Maheu, Rideau Hall, OSGG-BSGG)

Adina Bresge

Topic

Our Community

Temerty Faculty of Medicine

Unity Health

Institute of Health Policy Management and Evaluation

Alumni

Chemistry

Dalla Lana School of Public Health

Faculty of Applied Science & Engineering

Faculty of Arts & Science

Faculty of Music

Hospital for Sick Children

Leslie Dan Faculty of Pharmacy

Order of Canada

Political Science

St. Michael's College

University College

University Health Network

Victoria College

Subheadline

"The Order of Canada recognizes individuals who have made positive and lasting impacts on communities here in Canada or who have brought honour to our country abroad"

An innovator in chemical catalyst development. A global leader in cardiac surgery and care. And a public health expert who led the rollout of Canada’s first colon cancer screening program.

These are a few members of the ��ɫֱ�� community who were recently honoured with appointments or promotions within the Order of Canada.

The Governor General recently announced 83 new appointments to the Order of Canada, including two promotions within the Order.

They include Doug Stephan, a University Professor of chemistry in the Faculty of Arts & Science; Lee Errett, a professor in the Temerty Faculty of Medicine’s department of surgery, and Linda Rabeneck, a health executive and professor in the Temerty Faculty of Medicine and the Dalla Lana School of Public Health.

Established in 1967, the Order of Canada is one of the country’s highest honours, recognizing extraordinary contributions across all sectors of society.

“The Order of Canada recognizes individuals who have made positive and lasting impacts on communities here in Canada or who have brought honour to our country abroad,” Gov. Gen. Mary Simon said in a statement.

Here is a list of ��ɫֱ�� faculty, alumni and supporters who were appointed to, or promoted within, the Order of Canada in the latest round of honourees.

Current and former faculty

Edward Cole, a staff nephrologist at Toronto General Hospital and professor in the Temerty Faculty of Medicine’s department of medicine, was named a Member of the Order for his dedication to advancing and delivering care to people living with kidney disease, his instrumental role in establishing a globally impactful kidney-paired donation program and his leadership as former physician-in-chief at the University Health Network.

Lee Errett, a professor in the Temerty Faculty of Medicine’s department of surgery, was appointed a Member of the Order for his transformative leadership in cardiac research and care, including his role in establishing St. Michael’s Hospital as a world-class centre for cardiac surgery, his dedication to educating future medical leaders and providing care in underserved areas worldwide.

Franklyn Griffiths, a professor emeritus and George Ignatieff Chair Emeritus of Peace and Conflict Studies in the department of political science in the Faculty of Arts & Science, was appointed a Member of the Order for his scholarship on Russian affairs which has advanced the Western world’s understanding of Soviet politics. An expert in Arctic international relations, Griffiths helped create the Arctic Council and pushed for Indigenous voices to play a central role in the council’s workings.

Beverley Johnston, an internationally renowned percussionist who is an adjunct professor in the Faculty of Music, was appointed an Officer of the Order for her work developing and promoting Canadian music to audiences around the world. Working in a male-dominated field, Johnston’s unconventional performances combine classical transcriptions, contemporary music and an element of theatre.

Daphne Maurer, a professor emeritus of psychology, neuroscience and behaviour at McMaster University who holds a status appointment at ��ɫֱ��’s Institute of Health Policy Management and Evaluation in the Dalla Lana School of Public Health, was appointed an Officer of the Order for her research on visual and cognitive development in early childhood.

Linda Rabeneck, a gastroenterologist, health executive and professor in the Temerty Faculty of Medicine and the Dalla Lana School of Public Health, was named a Member of the Order for her leadership in colorectal cancer screening and prevention. Formerly the director of the Division of Gastroenterology at ��ɫֱ��, she led the rollout of ColonCancerCheck, Canada’s first province-wide screening program.

Stephen Randall, who earned his master's degree and doctorate at ��ɫֱ�� and taught at the university from 1971 to 1974, was named a Member of the Order for his academic contributions and advisory role in international relations. A professor emeritus at the University of Calgary, Randall’s expertise in myriad issues affecting the United States and Latin America, notably Colombia, has informed Canada’s foreign policy.

Bibudhendra Sarkar, senior scientist emeritus at the Research Institute of the Hospital for Sick Children and professor emeritus at ��ɫֱ��’s department of biochemistry in the Temerty Faculty of Medicine, was named a Member of the Order for his achievements in advancing medical research in Canada and abroad. He discovered a novel treatment for patients with Menkes disease, a rare genetic condition, and led international efforts in South and Southeast Asia to address public health crises from contaminated groundwater.

Jonathan Scott Rose, a professor in the Edward S. Rogers Sr. department of electrical and computer engineering in the Faculty of Applied Science & Engineering, was named a Member of the Order for his pioneering work in architecture and software used in field-programmable gate arrays. Rose served as the chair of the department from 2004 to 2009 and received his PhD degree in electrical engineering from ��ɫֱ�� in 1986.

Doug Stephan, a University Professor in the department of chemistry in the Faculty of Arts & Science, was named an Officer of the Order in recognition his world-leading research in inorganic and organometallic chemistry. His many achievements include discovering – and commercializing – a new class of catalysts that is now used in one of the largest chemical manufacturing facilities in the world. He also achieved global renown for founding the field of “Frustrated Lewis Pair” chemistry.

Alumni and friends

Sleight-of-hand artist David Ben, who graduated from University College in 1983, was named a Member of the Order for his four decades of dedication to the exploration, development and preservation of magic, including penning several books on the subject and co-founding the Magicana organization.

William Fox, a research fellow and adjunct professor at Trent University who earned his honours bachelor of arts and master of arts in archeology at ��ɫֱ��, was named a Member of the Order for his distinguished contributions to Canadian archeology, his leadership in the Ontario Archaeological Society, and his steadfast advocacy for the involvement of Indigenous communities in preserving their material heritage.

Martha Friendly, who founded the Childcare Resource and Research Unit at ��ɫֱ��’s Centre for Urban and Community Studies in the early 1980s, was appointed an Officer of the Order for her work with the now-independent non-profit and her advocacy for accessible, publicly funded early childhood education and care, and women’s equality.

Rosemary Ganley, a writer, activist, teacher and an alumna of St. Michael’s College, was named a Member of the Order for her lifelong advocacy for human rights, gender equity, and social justice, including co-founding Jamaican Self Help, an organization of Canadians working to support the development of healthy Jamaican communities.

Arnie Gelbart, a member of the Chancellors’ Circle of Benefactors, was named a Member of the Order for his decades-long leadership in independent film and television in his role as founder, executive producer and CEO of Galafilm Productions Inc.

Judy Kent was named a Member of the Order for championing sport as a catalyst for social change, her advocacy for gender equality and inclusion and her leadership in international support. Among her achievements: She was the first woman to serve as both president of Commonwealth Sport Canada and Canada’s chef de mission for the Commonwealth Games, and her paper on sport for international development laid the foundation for the SportWORKS program.

James David Meekison, with a 45-year career spanning investment banking, cable television and private equity, was named a Member of the Order for his extensive philanthropy. The Jim Meekison and Carolyn Keystone Foundation supported ��ɫֱ��’s Leslie Dan Faculty of Pharmacy’s efforts to launch the Discovery Pharmacy on the St. George campus.

Michael Perley, a ��ɫֱ�� alumnus who completed a master’s degree in French language and literature, was named a Member of the Order for his lifelong dedication to tackling environmental and health challenges. He has been an advocate for tighter tobacco control laws, reducing second-hand smoke exposure and has led coalitions on acid rain and air pollution.

Dan Poenaru, a pediatric surgeon and professor at McGill University who earned two degrees at ��ɫֱ��, was named a Member of the Order for his contributions to pediatric surgery in Africa, including establishing a surgical unit and training program in Kenya, co-founding three medical schools and leading initiatives for children's surgery globally.

Vaira Vike-Freiberga, an alumna of Victoria College and the first woman to serve as Latvia’s president, was named an honorary Officer of the Order for her work enriching Canada-Latvia relations and for reflecting Canadian values abroad.

– with files from Mariam Matti and Rahul Kalvapalle

How will AI change our world? ��ɫֱ�� podcast explores technology’s impact on society

Christopher.Sorensen — Thu, 04 Apr 2024 15:17:45 +0000

How will AI change our world? ��ɫֱ�� podcast explores technology’s impact on society

Christopher.Sorensen Thu, 04/04/2024 - 11:17

Mariam Matti

Topic

Our Community

Temerty Faculty of Medicine

Unity Health

What Now? AI

Schwartz Reisman Institute for Technology and Society

Alumni

Artificial Intelligence

CIFAR

Computer Science

Dalla Lana School of Public Health

Faculty of Arts & Science

Faculty of Information

Faculty of Law

Geoffrey Hinton

Leslie Dan Faculty of Pharmacy

Startups

��ɫֱ�� Mississauga

Vector Institute

Subheadline

In What Now? AI, hosts Beth Coleman and Rahul Krishnan explore – and demystify – artificial intelligence and its impact on society with the help of leading experts

Rapid advances in artificial intelligence are posing profound questions about the future – and about us.

Can we ensure safety and alignment within AI systems? How might AI forever transform fields like health care? What ripple effects could AI have on jobs and livelihoods, including in creative industries?

��ɫֱ�� researchers Beth Coleman and Rahul Krishnan explore – and demystify – these and other topics by tapping into the knowledge of leading AI experts in What Now? AI, a new ��ɫֱ�� podcast that launches this week.

It can be found on Apple, Spotify, Soundcloud, iHeartRadio and Amazon.

An associate professor at ��ɫֱ�� Mississauga’s Institute of Communication, Culture, Information and Technology and the Faculty of Information, Coleman says she hopes the episodes help audiences make sense of new AI tools and systems by cutting through “all the noisiness and controversy that has taken over the headlines.”

“It can be complex and technical, but it’s also social,” says Coleman, a research lead on AI policy and praxis at the Schwartz Reisman Institute for Technology & Society.

“What we do with AI makes a difference and more people need to be able to share that knowledge.”

Coleman’s own research centres around technology and society with a focus on data and cities, AI and policy, and generative arts. Inspired by Octavia Butler’s 1980 Xenogenesis trilogy, Coleman authored Reality Was Whatever Happened: Octavia Butler AI and Other Possible Worlds using art and generative AI.

Krishnan, meanwhile, is an assistant professor in ��ɫֱ��’s department of computer science in the Faculty of Arts & Science and department of laboratory medicine and pathobiology in the Temerty Faculty of Medicine. A Canada CIFAR AI Chair at the Vector Institute and Canada Research Chair in computational medicine, Krishnan and his team focus on teaching neural networks about causality, building deep learning models that analyze cause and effect from data.

“I’m excited to co-host this podcast to explore and demystify for a broader audience AI through the lens of an accomplished and diverse set of experts,” says Krishnan, who is also a faculty affiliate at the Schwartz Reisman Institute for Technology and Society and a faculty member at the Temerty Centre for AI Research and Education in Medicine (T-CAIREM).

What Now? AI picks up where the conversation started last year by Geoffrey Hinton, the cognitive psychologist and University Professor emeritus of computer science who is known as the “Godfather of AI.” After a lifetime spent developing a type of AI known as deep learning, Hinton stepped back from his role at Google to warn about the existential threats of unchecked AI development.

Since then, there have been ongoing advancements in AI research, technological applications and policy development.

Coleman and Krishnan will tackle these and other topics with guests:

Gillian Hadfield, professor of law and strategic management at the Faculty of Law and the Schwartz Reisman Chair in Technology and Society.
Roger Grosse, associate professor of computer science in the Faculty of Arts & Science and founding member of the Vector Institute.
Christine Allen, professor at the Leslie Dan Faculty of Pharmacy and co-founder and CEO of Intrepid Labs Inc.
Andrew Pinto, a family physician at St. Michael’s Hospital, Unity Health Toronto, and associate professor in the Temerty Faculty of Medicine and the Dalla Lana School of Public Health.
Nick Frosst, co-founder of Cohere, singer in Good Kid band and a ��ɫֱ�� computer science and cognitive science alumnus.

“The What Now? AI podcast highlights the incredible researchers at the ��ɫֱ�� who are exploring the profound implications of this transformative technology,” says Leah Cowen, ��ɫֱ��’s vice-president, research and innovation, and strategic initiatives. “These discussions tackle critical questions surrounding AI safety and alignment and its myriad implications across various domains.

“The university is committed to fostering informed discussions that will shape our collective understanding of AI’s role in our society and in our future.”

Coleman says she hopes listeners come away from the podcast feeling more grounded.

Krishnan, for his part, wants the audience to understand “that there is no one group that has ownership” over the technology” and that “the free exchange of ideas and open-source tools encourage people from all disciplines to come see how accessible AI can be, what AI can do for them and how they can advance the discourse in the field.”

Black Health Education Collaborative launches educational tool on racism and Black health in Canada

rahul.kalvapalle — Thu, 21 Mar 2024 18:13:47 +0000

Black Health Education Collaborative launches educational tool on racism and Black health in Canada

rahul.kalvapalle Thu, 03/21/2024 - 14:13

Cutline

L to R: Assistant Professor Onye Nnorom, Associate Professor OmiSoore Dryden from Dalhousie University and Assistant Professor Sume Ndumbe-Eyoh (supplied images)

Topic

Temerty Faculty of Medicine

Dalla Lana School of Public Health

Subheadline

The Black Health Primer aims to address gaps in education and training on Black health and anti-Black racism in medicine and public health

Scholars from the ��ɫֱ�� and Dalhousie University have created a set of online courses on Black health and anti-Black racism in the Canadian health-care system, which will be available to learners across Canada – a momentous step in helping advance equitable care for Black Canadians.

The Black Health Primer was created in response to gaps in education and training on Black health and anti-Black racism in medicine and public health, say its creators Onye Nnorom, an assistant professor at the Dalla Lana School of Public Health and Temerty Faculty of Medicine, Sume Ndumbe-Eyoh, an assistant professor at Dalla Lana and OmiSoore Dryden, the James R. Johnston Chair in Black Canadian Studies at Dalhousie University’s Faculty of Medicine.

The courses are intended for students, faculty, educators and health-care practitioners alike and can be used for professional development at health-related institutions and organizations, the founders say.

The initiative was developed by the Black Health Education Collaborative (BHEC), a group of Black scholars and practitioners committed to transforming medical and health professional education in service of improving the health of Black communities across Canada.

“Black people in Canada experience health and social inequities rooted in anti-Black racism,” says Nnorom, who co-founded the BHEC with Dryden. “The historical impacts of slavery on this land affect Black people today and influence the stereotypes they experience in health care.

“By providing education on the issues that Black communities are facing in their everyday lives, the racism they encounter in health care and better anti-racist approaches to care, we – the Black Health Education Collaborative – believe the primer can improve the quality of care Black Canadians are receiving.

“Furthermore, these modules were designed to support the ‘unlearning’ of racism and learning racially just practices which improve health for all.”

The BHEC, with support from Dalla Lana, Temerty Medicine, and Dalhousie University, will launch the Black Health Primer on March 21 – the International Day for the Elimination of Racial Discrimination – at an online event titled, "Why Anti-Racist Healthcare Matters."

“The Public Health Agency of Canada has highlighted that ‘anti-Black racism and systemic discrimination are key drivers of health inequalities faced by diverse Black Canadian communities,’ and yet health-care professionals – from doctors to public health professionals – are not taught about the ways in which anti-Black racism negatively impacts the health of Black communities,” says Ndumbe-Eyoh, who is BHEC’s executive director.

“This is a significant failing which leads to health professionals practising without the knowledge and skills required to provide adequate care for Black patients and communities.”

“It is our hope that the medical students, doctors, nurses, and students who are in other health fields will complete the training and be inspired to provide better quality care,” says Nnorom, who hosts the Healthcaring Differently social media campaign.

Registration for the Black Health Primer opened Thursday

COVID-19 took a mental health toll on mothers, young women and adolescent girls: Researchers

Christopher.Sorensen — Fri, 15 Mar 2024 19:31:22 +0000

COVID-19 took a mental health toll on mothers, young women and adolescent girls: Researchers

Christopher.Sorensen Fri, 03/15/2024 - 15:31

Cutline

(photo by skynesher/Getty Images)

Chloe Panganiban

Topic

Breaking Research

COVID-19

Institute for Pandemics

Institutional Strategic Initiatives

Sunnybrook Health Sciences Centre

Temerty Faculty of Medicine

Institute of Health Policy Management and Evaluation

Centre for Addiction and Mental Health

Dalla Lana School of Public Health

Mental Health

Research & Innovation

Women

Subheadline

“The current road towards pandemic recovery needs to consider these at-risk populations. If not, there could be dire long-term consequences for the current generation and ones to come”

Two new studies supported by the Institute for Pandemics – a ��ɫֱ�� institutional strategic initiative – show that the non-pharmaceutical public health measures implemented during the COVID-19 pandemic were associated with increased mental health visits for mothers with young children, young women and adolescent girls.

As governments around the world imposed public health measures to reduce viral transmission, including stay-at-home orders, travel restrictions, and school closures, experts raised concerns about the potential lasting impact on the mental health of individuals, especially those belonging to vulnerable and at-risk populations.

In particular, mothers with young children faced obstacles related to parenting and caregiving, while young women and adolescent girls experienced major disruptions to school, social and daily routines.

The new studies – which built on previous research showing the COVID-19 pandemic had a larger impact on the mental health of men compared to women – aimed to examine how these pandemic-related non-pharmaceutical interventions have impacted the mental health of these groups.

“This work raises concerns about how to contain and address this issue,” says Geoffrey Anderson, a professor at the Dalla Lana School of Public Health’s Institute of Health Policy, Management and Evaluation (IHPME) and lead of the pandemic recovery theme at the Institute for Pandemics.

“The current road towards pandemic recovery needs to consider these at-risk populations. If not, there could be dire long-term consequences for the current generation and ones to come.”

The research team also included: John Moin, a former post-doctoral researcher funded by the Institute for Pandemics; Shauna Brail, an associate professor at ��ɫֱ�� Mississauga who directs the Institute for Management & Innovation; and Simone Vigod, head of the department of psychiatry at Women’s College Hospital and a professor in the department of psychiatry in the Temerty Faculty of Medicine.

Both studies compared rates of doctor visits for mental health care in the pre-pandemic period from March 2016 to March 2020 to rates during the pandemic from April 2020 to November 2021.

The first, published in the Canadian Medical Association Journal (CMAJ) Open, found a rapid increase in doctor visits by mothers of young children for mental health care during the pandemic compared to the pre-pandemic period, with most of the care for mood, anxiety, depressive disorders and alcohol and substance abuse.

In the second study, published in the British Medical Journal (BMJ) Open, the team found an increase in doctor visits for adolescent girls and women aged 14 to 24 for mental health care largely driven by care for mood, anxiety and depressive disorders. Additionally, there was an increase in hospital visits for eating disorders for adolescent girls and women aged 14 to 19. There was no increase in doctor visits or hospitalizations for boys or young men.

Both studies show that the implementation of public health measures during the pandemic was associated with increased usage of mental health services among mothers of young children, young women and adolescent girls, and point to potential lessons for future public health crises.

“Our research raises concerns about the mental health impacts of public health measures on vulnerable women,” says Anderson. “We need to address these impacts as key part of any effective and equitable pandemic recovery strategy and we need to pay more attention to these consequences in future public health crises”.

"We saw the rapid and ongoing application of non-pharmaceutical interventions as public health measures throughout the pandemic,” says Moin, who was the lead author of both studies. “We also now know that they were associated with abrupt and prolonged changes in the utilization of mental health services. This association should be considered for future public health planning and strategy.”

Renzo Calderon, another post-doctoral fellow funded by the Institute for Pandemics, is leading a team that is further exploring this observed trend.

Despite nearly four years having passed since the beginning of the restrictions, the pandemic continues to alter the landscape of mental health. Hence, the researchers’ focus is not solely on exploring the overarching trends but also on better understanding if there are specific socio-demographic groups of women who were particularly affected.

Preliminary results indicate that the demand for mental health services around specific issues such as eating disorders and substance abuse, especially among young women, has not yet diminished.

Such a targeted approach aims to uncover nuanced insights into how the COVID-19 pandemic exacerbated these problems and lead to more effective interventions.

Mpox DNA can persist in the body for up to four weeks: Study

rahul.kalvapalle — Tue, 12 Mar 2024 20:04:03 +0000

Mpox DNA can persist in the body for up to four weeks: Study

rahul.kalvapalle Tue, 03/12/2024 - 16:04

Cutline

A sign containing information about monkeypox is seen in International Airport Treviso A. Canova, in Treviso, Italy, on Nov. 30, 2022 (photo by Manuel Romano/NurPhoto via Getty Images)

Betty Zou

Topic

Breaking Research

EPIC

Institutional Strategic Initiatives

Temerty Faculty of Medicine

Unity Health

Dalla Lana School of Public Health

ihpme

St. Michael's Hospital

Sunnybrook

Subheadline

The study is one of several projects supported by the mpox rapid research response launched by ��ɫֱ��'s Emerging and Pandemic Infections Consortium (EPIC) and its hospital partners

DNA from the mpox virus can be found in different parts of the body for up to four weeks after symptom onset, according to a study led by researchers at Unity Health Toronto, the Sunnybrook Research Institute and the ��ɫֱ��.

The researchers analyzed samples from 64 men who contracted mpox, including participants from the Mpox Prospective Observational Cohort Study led by Darrell Tan, an infectious disease physician at St. Michael’s Hospital, part of Unity Health Toronto – where some of Toronto’s first patients with mpox were identified and cared for – and associate professor in the department of medicine and the Institute of Medical Science at ��ɫֱ��'s Temerty Faculty of Medicine and in the Institute of Health Policy, Management and Evaluation (IHPME) at the Dalla Lana School of Public Health.

They found that persistence of mpox virus DNA varied depending on where the samples were taken from. Among the key findings was that the DNA was detectable in nearly half of genital skin swabs and one in five skin swabs from other sites a week after symptoms had resolved.

The study, which was published in Open Forum Infectious Diseases, is one of several projects supported by the mpox rapid research response launched by the Emerging and Pandemic Infections Consortium (EPIC), an institutional strategic initiative, and its hospital partners during the global outbreak of mpox – previously known as monkeypox – in 2022.

According to the World Health Organization, nearly 94,000 confirmed cases of mpox, including 179 deaths, have been reported from 117 countries since January 2022. As of September 2023, 1,515 cases have been confirmed in Canada, mostly in Ontario and Quebec.

“Even though we’ve known about mpox for over 70 years, it was new to us because we hadn’t seen it outside the endemic regions,” said Robert Kozak, one of the study’s authors and a clinical microbiologist at Sunnybrook Research Institute and assistant professor in the department of laboratory medicine and pathobiology at Temerty Medicine. “There was still a lot about the virus and disease that we didn’t know,”

To answer key questions about viral shedding, Kozak teamed up with Tan and Sharmistha Mishra, an infectious disease physician at St. Michael’s Hospital and associate professor in the Temerty Faculty of Medicine’s department of medicine and Institute of Medical Science and IHPME.

(L-R) Robert Kozak, Sharmistha Mishra and Darrell Tan (supplied images)

The researchers used a technique called quantitative polymerase chain reaction (qPCR) to determine the persistence of mpox virus DNA. Samples were taken from six different sites on the body — genital region, nasal cavity, semen, skin, throat and urine — and over an extended period of time.

On average, mpox DNA was detected in skin swabs from the genital and perianal region and from other skin sites at 30 and 22 days after symptom onset, respectively. These findings are consistent with the sexually transmitted nature of mpox during the recent global epidemic, which primarily affected gay, bisexual and men who have sex with men.

The researchers were unable to detect viral DNA in a large proportion of semen samples and nasal cavity swabs taken when individuals first presented with symptoms, whereas in urine and throat swab samples, mpox DNA persisted for roughly two weeks after symptom onset.

Interestingly, the researchers did not observe a difference in the length of viral DNA persistence between people who received the antiviral drug tecovirimat and those who did not. Tan noted that while study participants were not randomly assigned to receive the drug, these results underscore the uncertainty around tecovirimat’s effectiveness in treating mpox infections.

He added the study provides several key learnings for his clinical colleagues. “First, we’ve documented the breadth of clinical samples in which mpox DNA can be identified and therefore can be used to confirm a diagnosis. Our findings also reinforce that it’s worthwhile for clinicians to collect such samples in individuals where an mpox diagnosis is being considered, even after symptoms of feeling unwell are gone," Tan said.

The researchers caution that just because mpox DNA can be detected up to four weeks after symptom onset, it doesn’t mean that individuals are infectious for that long.

“We don’t know for sure whether the presence of detectable viral DNA necessarily means that the virus is transmissible to other people, so more research definitely needs to be done to determine definitively the period of infectiousness,” Tan said.

To that end, Jacklyn Hurst, a postdoctoral fellow in Kozak’s lab, recently started work in the Toronto High Containment Facility to look for live virus in the same samples from which mpox DNA was detected. The researchers are also using the facility’s biobank of mpox patient samples to identify biomarkers that could predict whether a person will have a mild or severe infection.

“Without the Toronto High Containment Facility, we wouldn’t be able to do any of this. Having that facility will help us answer a lot of questions about this virus and how to stop it,” said Kozak.

He acknowledged the immense contributions of the patient community to this work. “A huge thank you to all the study participants. We wouldn’t be able to do this work without their sacrifice and commitment.”

Dalla Lana School of Public Health

Caution needed when drawing links between improving symptoms and unproven remedies: Study

Sexual and Gender Minority Health Research, Centre for

Tags

Vaccine Preventable Diseases, Centre for (CVPD)

Tags

Occupational Disease Prevention, Centre for

Tags

Pandemics, Institute for

Tags

��ɫֱ�� community members recognized with Order of Canada

Current and former faculty

Alumni and friends

How will AI change our world? ��ɫֱ�� podcast explores technology’s impact on society

Black Health Education Collaborative launches educational tool on racism and Black health in Canada

COVID-19 took a mental health toll on mothers, young women and adolescent girls: Researchers

Mpox DNA can persist in the body for up to four weeks: Study