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This episode was filmed on September 27th, 2022. If major
new developments happen, we will update them in the
video description and make new videos as
necessary. [♪ INTRO]
With everything the COVID pandemic has put us through,
news of the circulating disease commonly known as monkeypox has weary folks thinking, not another
pandemic. But monkeypox is not a
pandemic. In July of 2022, the World Health Organization
declared it a Public Health Emergency of International Concern,
which is a different designation. It shares
this honor with COVID-19, which is a pandemic, but also polio, which is not.
Unlike SARS-CoV-2, which was a brand new coronavirus
in 2019, monkeypox is nothing new. It was first identified in
humans decades ago in 1970. It had rarely been recorded
outside of sporadic cases in Central and West Africa
where it has been endemic for decades. But as of the summer of 2022,
it’s been found in over a hundred
other countries, including the United States, Canada, Australia, and parts of Europe.
And in fact, there's now some evidence that our current
outbreak has been slowly burning since 2017, when Nigeria saw its first cases of human monkeypox
in almost 40 years.
And that’s not for sure yet, but the case is strong so we’re
going to treat it as somewhere between likely and “yeah,
this is a thing”.
And the current situation is different in a lot of ways from
disease outbreaks in the past. It’s different from COVID,
different from other diseases with a disproportionate
impacts in LGBTQ+ communities, and different from previous endemic human monkeypox outbreaks.
Stop thinking about it like it’s the same as anything else.
Now, before diving into the differences, a few basics up front:
Human monkeypox belongs to the genus Orthopoxvirus,
which also includes smallpox. Like smallpox, it is a large,
DNA-based virus that infects skin tissue. Smallpox only affected humans, allowing
us to eradicate it through worldwide
vaccination. Monkeypox, on the other hand, is carried by humans and animals.
So it’s harder to pin it down.
Over the last few decades, there have been two major
strains of the virus that researchers have identified,
currently referred to as Clade I and Clade II, where a clade
is a general term for a taxonomic group. These were renamed after having been
initially named after the parts
of Africa where they originated, so as not to worsen the geographic stigma associated with
the current outbreak.
In fact, we should note that the term “monkeypox” itself is
on its way out, partly because of the association with racist
slurs about Black people. Scientists also argue that
as a name, it’s simply inaccurate. The virus was initially discovered
in 1958 in a group of monkeys used for research,
not in Africa but in Denmark. But even though it was discovered
in primates, it has also been known to infect
all kinds of creatures, squirrels, hedgehogs, and mice. And it’s unclear
which animal it first appeared in.
Some researchers are using the rather clunky hMPXV, for
the human monkeypox virus, as a placeholder. They’re
urging the international committee that names viruses to
make a speedy decision on a new name But for the purposes of this episode,
we’re going to call it human monkeypox despite the term’s flaws.
And if you’re betting on where we’ll end up, the name
Smart money may actually be on “human monkeypox virus” or “human simian orthopox virus”
becoming the official name.
I don’t make the rules, I’m totally calling my shot though. I think human simian orthopox virus
Now the first main difference between previous outbreaks and the current outbreak is how humans
contract the disease. Reported cases in
humans previously came from direct contact with infected animals, known as zoonotic
transmission. We’re going to call that “zoonotic monkeypox” for the rest of the video.
For instance, in 2003, a suspected 47 individuals in the
U.S. caught it from infected prairie dogs purchased from
pet shops. Rarely, infected pregnant people could transmit
it to their child during gestation and birth. But in recent years,
humans have been catching it from other humans, also known as human-to-human
transmission, which we’ll be calling human monkeypox.
This isn’t a hundred percent new, as it’s been seen in
endemic versions of the virus in the Democratic Republic
of the Congo. But right now,
and since 2017, sexual activity has been in the mix as a driver of the virus’s spread.
Note that human monkeypox isn’t classified as a sexually
transmitted infection. As far as we know, close contact
during sex just presents it with a good opportunity.
So we should be cautious about inviting comparisons to
HIV, despite the similarity in the communities affected.
More on that in a moment. Researchers are working to
determine whether people can catch it through genital
excretions. But there is currently no evidence of transmission via these fluids.
Instead, sexual contact with an infected individual
increases someone’s skin-to-skin exposure to the virus,
which is the main way it spreads. Handling contaminated
bedding and clothes is another potential way to catch it.
It’s also possible that prolonged face-to-face exposure to
respiratory droplets during sex can spread human monkeypox, though it’s not airborne in the way
measles is.
Another main difference between the current human monkeypox outbreak and other disease outbreaks is
the visibility of the inequity between wealthy and poor
nations. Even though human monkeypox is not new, this new
outbreak has re-ignited a conversation about wealthy
nations ignoring diseases until they become a direct threat.
Because people outside of the endemic region have started to pay attention for a change.
But those in Sub-Saharan Africa are pointing out that they
had been sending out an SOS for decades, and the only
difference is that other countries are finally taking notice.
Unfortunately, taking notice has also meant that there’s
well placed concern about the hoarding of resources,
including vaccines, by wealthier nations. The hope was
that nations would distribute vaccines based on the
populations at highest risk and not based on who can pay
for them. Already, however,
wealthy nations like the US and the UK seem to be snapping up supplies.
The third difference is the more attention researchers
have paid, the more they've realized that the virus
itself has defied their expectations for how it should
work. That means human monkeypox had been more pervasive and widespread than they thought.
As we mentioned, this virus stores its genome in DNA like
most organisms, not RNA like many viruses, including the
one that causes COVID-19. Usually, DNA viruses mutate 100
times slower than RNA viruses do.
One main reason for this is that the enzyme that most RNA
viruses use to replicate can’t proofread its work for
mistakes… something DNA viruses can do. So a poxvirus
would be expected to mutate once or twice per year.
Genomic analyses of virus samples collected from various
sites between 2018 and 2022, including one published in
the journal Nature Medicine in June, reveal something
surprising. The human monkeypox virus changed faster
than expected over those years. Somehow, between 2018 and 2022,
clade II of the human monkeypox virus, the one that spurred the Nigerian
outbreak, acquired over fifty mutations. That’s around
6-12 times more than the typical mutation rate for this
type of virus. It’s changed enough for
the World Health Organization to determine that the currently
circulating flavor is a third distinct strain, called Clade IIb,
while older versions now belong to Clade IIA.
The specific changes between these variants suggest that
human immune defenses may have helped inadvertently
speed up mutations. A host’s immune
arsenal includes enzymes that edit a virus's genome while it tries to replicate,
which can disable it.
But sometimes, these edits don’t disable a virus. Instead of
preventing a virus from churning out more copies of itself,
the edits themselves get copied and make it into the viral
offspring. However these mutations
came to be, they seem to affect the shape of a specific protein
on the surface of the virus that helps it infect host cells.
It’s possible that a tweak in its machinery might be helping
it infect and spread more easily, though it remains unclear
how much more easily, if at all.
Those fifty mutations then had to reach the right place at
the right time. Well, the wrong place at the wrong time. The
change from zoonotic to human-to-human transmission
probably occurred in time to spur the start of the present
outbreak in Nigeria in 2017. We don’t know much about how
that outbreak started, but even back then, the first
patient in 2017 probably got it from a member of their household,
not from interaction with wildlife. So, already
human transmission, not zoonotic. Further shifts in human behavior,
in addition to the suite of mutations, probably converged
to spur further spread, until just the right social situations
occurred in 2022 to allow things to take off.
COVID lockdowns, event cancellations, and just people
staying at home taking fewer risks probably slowed monkeypox too. And getting back
out there post-lockdown has had the opposite effect.
Not only has its genome changed. The newest variant
of human monkeypox seems to have different symptoms from the classic manifestation
of zoonotic monkeypox.
With zoonotic transmission, systemic symptoms like fever
and feeling generally bad tend to occur before the lesions.
Several hundreds of these pox then typically appear on
multiple parts of the body. This usually includes the face,
arms, legs, and sometimes the palms of the hands, soles
of the feet, and genitalia. With more recent cases of human
monkeypox, patients aren’t necessarily
experiencing general malaise before lesions pop up. And instead of hundreds
of lesions, several of those who have been
diagnosed during this outbreak have just one or a few lesions.
An analysis of cases in central London published in the
British Medical Journal in July of 2022 also notes that
patients who contract this version can experience penile
swelling and rectal pain. Along with other experts,
the authors of this case study point out that these
different symptoms should be added to public health messaging to reduce transmission.
The ubiquity of this disease seems like a big difference
between previous outbreaks and this one. But researchers
are realizing that there could have been more transmission
in non-endemic countries than was reported over the
years. It’s also
clear that silent human-to-human transmission within and outside of endemic regions went
underreported prior to 2017. And it’s also possible that cases
of human monkeypox were misdiagnosed
as sexually transmitted infections because the symptoms didn’t match the old school
zoonotic version. Waning smallpox immunity
is another thing that’s changed over the years. The proteins on
the surface of the two viruses are shaped
similarly enough that immune memory to smallpox can offer protection
against monkeypox. That’s why the two currently
available vaccines against human monkeypox in the U.S. are also
approved for smallpox. In 2019, a group of
epidemiologists and pharmaceutical consultants met in London to discuss
the increasing threat of monkeypox. In 2020,
they published a report of their meeting in the journal Vaccine.
In it, the authors explain that the proliferation of human
monkeypox seems to be an unintended consequence of the successful eradication of smallpox.
Starting in the 1950s, routine vaccination was implemented
worldwide in a concerted effort to wipe out smallpox
altogether. That routine vaccination
stopped in the 70s when the effort proved successful. There was no
more smallpox. It’s one of the greatest triumphs
of humanity ever. Over time, immunity among the global
population has dropped as the vaccinated population has gotten old and died.
Yet another potential change that triggered this outbreak
is urbanization and deforestation, which have increased
human contact with forest animals. And this is just an abridged list of the complex
convergence of changes that set the stage for this Public
Health Emergency of International Concern. Researchers
are still working to tease out the relevant factors.
And that brings us to the next way that human monkeypox differs from COVID-19—the community it
affects. It’s crystal clear
that COVID-19 is everywhere and can infect anyone in its vicinity,
if given the opportunity. When human monkeypox was thought to be almost
exclusively transmitted from animals to humans, it didn’t
seem to disproportionately affect people of specific gender
or sexual orientations, though it did affect younger
patients. But some of the messaging around the 2022 human
monkeypox outbreak suggests that it’s a so-called gay
disease. You will no doubt
have heard that human monkeypox is disproportionately affecting
the community of men who have sex with men, or MSM,
which is the term used in public health research.
I’m actually going to hang a big asterisk on this point. The
2017 Nigerian outbreak, in other words, probably this
one, has also been pinned to risky sexual behavior.
That’s not moralizing about who or what you’re doing. It’s
intended to be a value-neutral description of behaviors
more likely to transmit disease, like having multiple
partners, having sex with sex workers, and this is the key
part, not using barrier protection. Here in the US, we can see that this
is affecting the MSM community. And if
you’re following English-language media, that’s the impression you’re going to get.
What we really know is that the spread of human monkeypox is tied to these
risky behaviors. Though being an MSM can make the list, it’s not the only thing.
To be clear, there’s no such thing as a “gay disease”.
Advocates have noted disturbing parallels to the gross
mishandling of HIV and AIDS in the 80s and 90s when
systemic discrimination and homophobia led to the neglect
and stigmatization of the entire gay community. That’s one reason LGBTQ+ folks are
at the forefront of working to dismantle
the stigma around diseases that circulate in those community.
They have also been behind the push to disseminate
information, vaccination, and services for the current outbreak.
As for the virus itself, the human monkeypox virus is no
HIV. As of September 23rd, 2022, 23 human monkeypox
virus deaths have been reported worldwide all year. By
contrast, in 2021 there were over half a million deaths from
HIV-related causes worldwide. This time around, some governments are making a
concerted effort to talk frankly about sex in a way that they
failed to do back then. Some public health
agencies are issuing a lot more useful and specific guidelines for safe sex than
they did in the 80s.
This includes warning folks that spaces like sex clubs or
parties where intimate sexual contact takes place are
particularly likely to spread the disease. It also urges folks
to be sure to change or clean clothes and gear between
sexual partners and after use. And it explains that while
condoms may protect someone's anus, penis, vagina, or mouth
from infection, they can’t prevent skin-to-skin
exposure to other body parts. And that’s how this disease is transmitted
With all that said, some advocates are concerned that
they’re witnessing a gravely inadequate response that
brings up worrying parallels to what they saw in the AIDS
pandemic. Even in wealthy nations, they say, responses
like vaccine distribution have been bafflingly slow.
In the end, experts say that this is no more a gay disease
than an African disease. Ultimately, it seems most likely
that the aforementioned series of factors converged
inadvertently to trigger this outbreak that has been
concentrated among people who practice high-risk behaviors. In some cases overlapping with MSM.
But officials have made clear that the virus can spread
readily in any densely-connected sexual networks. It does
infect women and people of other genders and orientations.
And it can most definitely pass to other members of the
household or other close contacts with no sexual activity
whatsoever. Again. A virus that is taking
advantage of sex to spread is not ipso facto an STI.
Officials have also noted that the high rate of reported
infections among MSM could be partly due to this community having a tendency
to be proactive about sexual health and seek testing more often than other
communities. But again,
this is just one element in a complex disease landscape, and the role that increased
surveillance among MSM plays in the number
of recorded cases is still unclear. So there you have it. In many ways,
it serves us to treat every disease differently,
so in that sense this is not COVID or HIV all over
again. The mistakes of the past still loom, though, as something that must be avoided.
Researchers, officials, and community advocates continue
to iron out the details, like diagnostic tools and surveillance,
effective and equitable distribution of resources, and epidemiological questions.
And the good news is, as of September 23rd, it appears to
be working! The World Health Organization reports there’s
been a 22 percent drop in reported cases in North America
and Europe in the past week. With over
62,000 cases worldwide, and most in those two regions, this is an encouraging downward trend.
But like we know from COVID, trends that go down can go
up again. So in the meantime, it’s a good idea to stay
vigilant about human monkeypox. But it is at least slightly
reassuring that it is not the same as previous disease
outbreaks, and the public health outreach appears to be
working. If you enjoyed this lengthy
meditation on global equity as it pertains to infectious disease,
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Each month represents one digit of pi. So we won’t have a
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the description! [♪ OUTRO]