Monkeypox

Less than three months since it launched, the monkeypox rapid research response led by the University of Toronto’s Emerging and Pandemic Infections Consortium (EPIC) and three partner hospitals is generating results that could help curb transmission of the virus.

“When monkeypox first arrived in Canada, we quickly learned about the stockpile of smallpox vaccine [which also protects against monkeypox],” said Jesse Knight, a PhD student in �Թϱ��’s Institute of Medical Science in the Temerty Faculty of Medicine. “Given that the vaccine supply was quite limited early on, it was important to use it quickly and efficiently to help reduce cases.”

Knight is the first author on a new modelling study that looks at how to optimize the initial rollout of vaccine to prevent the most infections. The study, which has not yet been peer-reviewed, suggests that the greatest number of infections could be prevented by prioritizing vaccines to bigger cities with larger networks of communities at risk, the highest epidemic potential and largest number of initial cases.

Knight notes these results do not mean that areas outside of big cities should not receive vaccines, but rather they provide guidance on how to maximize immediate impact – early in an epidemic – of an extremely limited supply until more doses become available. Indeed, while Ontario’s vaccination efforts initially centred on Toronto, they soon expanded to areas outside the city.

Darrell Tan and Sharmistha Mishra

The preliminary findings were co-authored by Knight’s academic supervisor Sharmistha Mishra and collaborator Darrell Tan, both clinician-researchers at St. Michael’s Hospital, Unity Health Toronto, and associate professors in �Թϱ��’s Temerty Faculty of Medicine.

Mishra and Tan are also co-leads of EPIC’s monkeypox rapid research response. EPIC is one of several �Թϱ�� institutional strategic initiatives.

For their study, the researchers built a mathematical model that simulated the potential transmission of monkeypox virus in the context of sexual networks of gay, bisexual, and other men who have sex with men. The model reflects two interconnected sexual networks that can be thought of as communities within two cities – one larger network like in Toronto and a smaller network in a medium-sized Ontario city – and simulated the roll-out of 5,000 vaccine doses starting two months after the first case of monkeypox.

The team tested scenarios in which they changed the relative population size in each network (i.e., city), the interconnectedness between the two sexual networks (sex among individuals between cities), epidemic potential of the virus in each city and the distribution of initial “imported” cases across cities.

A city’s epidemic potential reflects how likely a person carrying the virus is to pass it on to others by taking into account the density and configuration of the sexual network, access to prevention and care and the underlying social and structural contexts that shape sexual networks and shape access.

“Early insights from these analyses helped inform vaccine prioritization by health units across Ontario, which to date has centred on community-based organizations, service providers, health units and public health teams at every level working together to mobilize access and deliver vaccines to gay, bisexual and other men who have sex with men who may be most at risk of infection,” said Mishra.

From the start, Mishra said, community leadership has been at the forefront of the response, including the science – with modeling questions, inputs, interpretation and application shaped by communities and the public health actors working to serve communities.

Knight hopes that this work will also have an impact on how vaccines are deployed globally.

“Given our increasingly connected world, our findings really highlight the importance of global vaccine equity in responding to outbreaks, and also in preventing them in the first place," he said.

Vaccines can help break chains of transmission when deployed strategically, but another opportunity to stop transmission is in the environment — where people infected with the virus may shed it onto surfaces and objects.

“We knew very little about fomite [surface] transmission of monkeypox prior to this outbreak,” said Christopher Kandel, an infectious disease physician at Michael Garron Hospital, Toronto East Health Network, and assistant professor in the Temerty Faculty of Medicine’s department of medicine.

To study the risk of environmental transmission of monkeypox, Kandel and Sharon Sukhdeo, an infectious diseases resident at �Թϱ��, teamed up with EPIC faculty members Allison McGeer, who is at Mount Sinai Hospital and is a professor in the Temerty Faculty of Medicine and at the Institute of Health Policy, Management and Evaluation (IHPME) in the Dalla Lana School of Public Health, Adrienne Chan, who is at Sunnybrook Health Sciences Centre and is an associate professor in the Temerty Faculty of Medicine and the Dalla Lana School of Public Health, and Matthew Muller, who is at St. Michael’s Hospital and is an associate professor in the Temerty Faculty of Medicine and at IHPME.

For the first part of their study, the team swabbed a mixture of high- and low-touch surfaces in hospital exam rooms where patients with monkeypox had received care. They tested the same surfaces again after the rooms had been cleaned.

Their preliminary results showed detectable levels of monkeypox DNA on many high-touch and a few low-touch surfaces. Encouragingly, the researchers could not detect the virus on the majority of surfaces after cleaning. Where they did detect the virus after cleaning, levels were significantly reduced.

Kandel notes that while they were able to detect monkeypox DNA, their methods can’t determine whether the detected virus was infectious.

As a next step, the researchers will expand their study to look at environmental transmission within households. They will ask people who are self-isolating with monkeypox to swab objects and surfaces in their home at different timepoints, which will provide insight into how long an infected person sheds the virus and whether common at-home cleaning products can effectively disinfect contaminated surfaces.

“There are so many questions that need to be answered,” said Kandel. “With these studies, we’ll have a much better understanding of monkeypox transmission, including how infectious people are and how long isolation should last to best protect others.”

�Թϱ�� expert Kerry Bowman on monkeypox and the danger posed by zoonotic diseases

Christopher.Sorensen — Thu, 28 Jul 2022 17:34:19 +0000

�Թϱ�� expert Kerry Bowman on monkeypox and the danger posed by zoonotic diseases

Christopher.Sorensen Thu, 07/28/2022 - 13:34

Cutline

(Photo by James Carbone/Newsday RM via Getty Images)

Mariam Matti

Topic

Global Lens

Monkeypox

Temerty Faculty of Medicine

Faculty of Arts & Science

Global

School of the Environment

The World Health Organization recently declared monkeypox – a disease that’s been a concern in African countries for years – a global public health emergency.

Monkeypox has been spreading globally in recent months with 75 countries reporting cases.

Yet, while the WHO issued its highest level of alert, that doesn’t mean monkeypox is highly contagious or necessarily lethal, says Kerry Bowman, assistant professor in the department of family and community medicine in the Temerty Faculty of Medicine and the School of Environment at the Faculty of Arts & Science.

“It doesn’t mean we’re facing a situation like COVID-19,” says Bowman. “[But] I think it’s a good decision. It’s been in Africa for some time, and it is now emerging in new parts of the world.”

A joint research effort by the university and partner hospitals – including University Health Network, Sunnybrook Research Institute and Unity Health Toronto – is underway to study the global monkeypox outbreak. The team’s findings will help inform a public health response to the outbreak in Canada and support efforts in other countries where the virus is endemic.

�Թϱ�� recently spoke with Bowman about the WHO’s designation of monkeypox as a global health emergency, how that might change the international response to the outbreak and what can be done to address the rise of zoonotic diseases more generally.

What does the WHO designation mean?

What it means is that we we've got a disease of concern that’s spreading globally. There’s no question about that. It does not necessarily mean that this is highly contagious or that it’s highly lethal. You might remember the WHO did this for Zika, which may not have had implications for many of us.

So, it doesn’t mean that we’re facing another situation like COVID-19. The WHO was fairly divided on whether it was necessary to trigger the highest level of alert. But I think it’s a good decision. It’s been in Africa for some time, and it is now emerging in new parts of the world.

How might the global response to monkeypox change with this new designation?

What it could mean in the future is travel warnings and restrictions. People coming from countries with a high prevalence of monkeypox, which is the United States and parts of the European Union right now, could experience higher screening at airports. If a person is unwell and officials suspect it is monkeypox, they could order quarantine or containment. I stress the word “could” in this scenario.

I hope it will encourage countries like Canada to get moving on monkeypox before it really takes root – to get ahead of it in terms of vaccination and vaccination supply. From a public health point of view, it’s important to make sure that this can be curtailed before it becomes something that’s endemic here.

What more could be done to lower the risk of transmission?

Vaccine access and education is huge. At this point, it should be readily available, and people should decide for themselves whether they want it or not.

The other concern I have is that until very recently our leaders are being opaque on how much vaccine we have, what our situation is with vaccine and what our plans are with it. Democracy and public health should never be opaque. You really need to let the public know what we’re dealing with.

Right now, it’s not clear as to what our vaccine supplies are and whether we have enough longer term. It’s still a very slow, inconsistent process to receive vaccination.

One element I think we’re ignoring on a global level is: where are all these awful diseases coming from? Monkeypox, without question, has an environmental and climate change component to it. It's not the only factor, but it's clearly a contributing factor. We continue not to look at the upstream causes of zoonotic diseases – diseases that come from animals just as this did.

Can you expand on that?

There’s a connection related to climate change and biodiversity loss that we’re simply ignoring.

What’s happening is, as more and more forests are cut down and the climate changes in Africa and other tropical regions, you have more non-human species moving around and being hunted. The interaction between animals and people is rising as there’s both environmental degradation and habitat loss. We’re opening up more tracts of what was once pristine forest and exposing people to those viruses.

The number of zoonotic diseases that are rising is significant.

How can we address this?

In the early days of the COVID-19 pandemic, we had some awareness of this – but there’s next to nothing being done to prevent more of these diseases from emerging.

It’s a real shortcoming of Western medicine that we have these firewalls where we don’t cross over into anything environmental. It’s the way we’ve organized ourselves – to our determent.

We need much more of a “One Health” approach. One Health and planetary health is something that looks at how all these systems work together – human, non-human and biodiversity.

In national and global planning, we should be looking at the consequences of mass deforestation in equatorial regions. We should also look at the health and wellbeing of ecosystems within Canada and the health of the animals.

For human health to flourish, we need to look through the lens of our environmental parameters.

Monkeypox

Monkeypox studies suggest ways to reduce viral spread

�Թϱ��� expert Kerry Bowman on monkeypox and the danger posed by zoonotic diseases

�Թϱ�� expert Kerry Bowman on monkeypox and the danger posed by zoonotic diseases