There are multiple sexually transmitted
infections and a handful of those are not
curable. Herpes is one of those. It's kind of
like the gift that keeps on giving that you
don't actually want. So in today's video,
we're going to talk about why our bodies
can't get rid of herpes, the different
types, how you spread or contract herpes,
and even some potential treatment options, and
can you actually have herpes and not even know it?
It's going to be a revealing one. So, let's
jump right into this and anatomical awesomeness.
[Intro]
Herpes is a viral infection that typically
manifest on the skin as vesicular lesions
and a vesicular lesion or a vesicle is
like a blister and these will eventually
ulcerate and even crust and scab over as
healing occurs. Now, herpes is caused by
one of two different viruses, although there
have been people that have contracted both.
One is called Herpes Simplex Virus Type 1 or
HSV-1 and the other is called Herpes Simplex
Virus Type 2 or HSV-2 . Now, HSV-1 is most
often associated with sores a the mouth and
the lips often referred to as cold sores
or fever blisters whereas HSV-2 is most
often associated with sores around the genital
structures and even the anus but there is some
potential crossover between these two viruses
and that has to do with how you contract them.
HSV-1 is typically contracted or spread through
direct contact with infected oral secretions
from someone who has HSV-1 and this is actually
often done during childhood. Say like a parent or
a sibling has a visible act of lesion and this
infected oral secretion gets transferred from
say like kissing or sharing of other various
items that eventually make it to the mouth.
Now, keep in mind you don't technically
always have to have a visible lesion to
spread HSV-1 because there are some people
who have these mild reactivations of this
infection which we'll get to in a minute
when they could potentially spread it,
it's just that when they do have visible larger
lesions, these lesions tend to shed more virus,
have an increase viral load and therefore
increase the risk of transmission.
Now, because of how HSV-1 is typically spread
like this through these infected oral secretions,
it's not technically or genitally classified
as a sexually transmitted infection. Although
there are some exceptions to this. However,
HSV-2 is typically classified as a sexually
transmitted infection because again, it is
most commonly transferred or contracted
through direct contact of genital
structures from an infected person.
So, let's cover one thing that many of you are
probably thinking about - is it possible to get
HSV-1 in the genital region as well as HSV-2
around the mouth or the lips? And the answer is
yes. Both virus types have been isolated from both
genital lesions as well as oral lesions. It's just
that more commonly again, HSV-1's found around
the mouth and HSV-2 around the genital structures.
Now, obviously this transfer would occur through
oral forms of intercourse. Say if somebody had
an active infection or HSV-1 around the mouth
and they performed a form of oral intercourse,
that could transfer HSV-1 to the genital structure
and vice versa is also true. Somebody had HSV-2
in the genital region, it could get transferred
to the mouth through oral forms of intercourse.
So now, we need to discuss why is herpes the
gift that keeps on giving or in other words,
why does our immune system have such a hard time
completely eradicating this virus because those
of you who've experienced herpes like cold sores
or other various manifestations of the infection,
you may have got a pretty good idea that you
can have flares where the lesion show up and
then they heal and go away and then you can have
another flare and there's a lot of variability on
how often or how frequently people can experience
these flares. And for us to understand how this
is working, we need to talk about what's known
as the primary infection and then, how the virus
kind of sets up in this latent kind of phase
and then can actually reactivate periodically.
So, when a person is first exposed to the
virus, the virus will infect epithelial cells
and epithelial cells make up the surface
of your skin and even some of your mucus
membranes like mucus membrane would be the
inside lining of your mouth but this virus
will literally get inside these epithelial
cells and start to replicate and copy itself.
Next, and this is really important for our discussion,
the virus will move into a sensory neuron
that's close by or associated with that
area of the skin or those epithelial cells
and once it moves into that sensory neuron,
it's going to travel up the neuron towards
something called a Sensory Ganglion.
Now, I know Ganglion is kind of
weird word but just stick with me with this
for a second because the sensory ganglion
is a collection of neuron cell bodies and
the cell body of a neuron is where you'd find
like the nucleus and other organelles. Now,
if this is an oral infection, it's going to set up
in this ganglion called the Trigeminal Ganglion.
Many of you may have heard of the trigeminal
nerve. It's a great sensory nerve of the face.
It serves many of the - much of the skin of
the face and if it's a genital infection,
it will go into what's called a Sacral Ganglion.
Now, the reason I'm bringing up this discussion
about the ganglion is because this is where the
kind of evades parts of our immune response
and sets up this latent lifelong infection and
let me go back to the beginning of this process
when the virus first gets into those epithelial
cells. This is the start of what's known as the
primary infection and what's interesting about
the primary infection is that many people are
asymptomatic but when people do have symptoms,
that can include these painful vesicular lesions,
swollen lymph nodes and even things like headache,
fever and even malace which is this term
for just 'blah, I don't feel well.' now,
when symptoms are present, they can start
anywhere from two to 12 days after exposure and
as the vesicular lesions are present, those
can last anywhere from one to three weeks,
with the genital HSV lesions tending to last
toward closer to that two to three-week range.
So, what happens after our body
deals with the primary infection? Well,
this is when the latent phase of the infection starts where that
virus is kind of being contained within that sensory ganglion.
Now, keep in mind that our body or immune,
even though it can't fully eradicate the virus,
it can deal with it to a certain degree. For
example, our body heals and improves from that
primary infection and with the recurrent
infections that we're about to talk about,
people who've experienced those know that the
lesions can come and then the body can heal.
So, our body does have this ability especially
from the perspective of the skin to heal those
skin lesions and I kind of think of it as
the immune system pushing the virus back up
into that sensory ganglion, kind of containing it
until a potential reactivation infection occurs.
Now, when, how often, or how frequently these
reactivation infections occur and even if they
occur, there's a variety of factors. Host
factors like you, your own immune system,
things that are within you that are unique to you
influence that as well as environmental factors.
Some things that are thought to influence
the reactivation of this virus are things
like immuno deficiency - the immune system
not working properly, stress, sunlight,
and even a fever. That's why these are often
referred to as a cold sores or fever blisters
because people will notice that they pop
up when they have a cold or even a fever.
Now, when this reactivation phase occurs,
the virus will reenter its replication cycle
and move back down that sensory neuron to the
area of the skin that that sensory neuron
serves and reenter those epithelial cells
and start to copy itself and this is when
the vesicular lesions will start to reform.
Now, this process also explains why some people
will experience what are called prodromal
symptoms and these are symptoms that can one
to two days prior to the vesicular lesions or
blisters actually forming and these symptoms
typically include things like pain, burning,
tingling, and even itching in the pathway of
that neuron prior to the lesions even forming.
And let me reiterate something that I mentioned
earlier. Again, the frequency and the severity
of these reactivation infections or these
flare ups or outbreaks varies greatly among
individuals. For example, I've had plenty of
patients who have tested positive for HSV,
especially HSV-1 or they're like, "I've never had
a cold sore in my life" and I will say to them,
"Well, you're probably one of those that were
asymptomatic during the primary infection or at
least the primary infection was very mild and
you probably didn't notice it much and just
kind of went on your way and your body probably
just does a better job containing that infection
rather than allowing it to kind of have these
flare ups or outbreaks." Now, another thing
that's interesting to consider is that the
primary infection in general, the severity
of this tends to correlate with the frequency
and the severity of the outbreaks. The worse the
primary infection, the more severe and frequent
the outbreaks or reactivation infections can be.
Another thing that we want to consider is that
HSV-2, the genital infection of HSV-2 is also
much less forgiving and what I mean by that is
you are more likely to have outbreaks with HSV-2,
genital infections than you are
say with like an oral HSV-1 infection.
So, if we can't cure this or completely eradicate
the virus, is there anything we can do for these
reactivation infections or these flare ups? And
the answer is yes. For example, there are topical
medications available that people will try to use.
Most of these topical medications are ointments
that help with the discomfort and the pain.
Certainly, topical lidocaine could help numb down
that pain and make the flare a little bit more
bearable but the medications that tend to have the
most data and be the most effective are a group
of antiviral medications and some of the common
antiviral medications used for HSV are things like
Valacyclovir, Acyclovir, and even Phamcyclovir.
Now, these medications are fairly accessible,
generic, and fairly inexpensive and they tend
to work if you use them properly or at least
they tend to help because they don't kill the
virus but what they do is help to slow down
the replication of the virus because remember,
during this reactivation infection or this
flare, the virus is going to reenter its
replication cycle and start copying itself so
these medications can help inhibit that and
kind of helps bolster the immune system to kind
of push this virus back into its latent phase.
And again, as I mentioned earlier, these
medications need to be used correctly and
what I mean by that is when I have a patient who
has, for example, these outbreaks, I'll say, "You
need to initiate these medications as soon as you
feel the sores might be coming on" and my patients
who do the best are those that recognize those
prodromal symptoms that we mentioned earlier.
Remember, sometimes people will notice
that tingling, that burning, the pain,
before the sores will even form and as soon
as they fill those symptoms, initiate the
medication because the medication again does not
kill the virus. It just inhibits its replication.
So, if somebody already has the sores formed for
like a day or two, these antiviral medications
won't do much but if they initiate them early
enough, what they'll notice is that the length
of the outbreak, the time they're experiencing the
sores, tends to shorten and even potentially helps
with the severity and one other way I want to
mention that these medications could potentially
be and this would be reserved for people who have
more severe and frequent outbreaks. A patient
in this situation might opt with their health
care provider to be on a lower dose or a lower
maintenance dose if you will. So, they would be
on a lower dose every single day and hopes that
it could help reduce the chances or the risk
of these frequent and more severe outbreaks.
And so let's wrap this up with a few housekeeping
items. In this video, we've been talking about
herpes and how it affects the mouth or the
genital regions but many of you may have heard
that herpes can affect other regions of the body
as well. For example, it can affect the finger,
that's called herpes whitlow. It can even affect
the eye which is called herpes keratitis but those
will be for some other future videos that we
can get very excited about but I do want to
wrap this up by talking about the importance
of teaching as well as lifelong learning.
One of my favorite things about teaching anatomy and physiology
and just about the human body is
the ability to apply that information
to real-world situations like how does
this knowledge of anatomy and physiology
help to better understand something like
herpes or other diseases and conditions.
So, if you enjoy learning how to better apply
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