– [Voiceover] Gastroenteritis
is often referred to as the stomach virus. If you've ever had the stomach virus, then you'll probably
know some of the symptoms associated with it. These include diarrhea,
vomiting and nausea, and dehydration. What exactly is causing
all these symptoms? I think the word stomach
virus can give us a good hint.
can be caused by a bacteria, but, for the most part, it's
caused by some kind of virus, and there are really many types
of viruses that can do this. Some examples could
include the adeno virus, the sapa virus, the rota virus, the noro virus, and the astro virus. A lot of different viruses
can cause gastroenteritis, and this is really just a handful of them. How do we know if the infection
is viral or bacterial? For one, if you have a viral infection, your diarrhea tends to be watery, whereas if you have a bacterial infection, it's more likely gonna be bloody.
In addition to that, people
with bacterial gastroenteritis will experience more fevers. Now, I don't want to be
completely absolute here, sometimes there are exceptions
where a bacterial infection can cause watery
diarrhea, but, in general, this is the pattern to look out for. How did the virus get into
your system to begin with? It's usually through fecal
to oral transmission. The feces of someone
who has gastroenteritis will be contaminated with the virus.
Let's say you know someone
who has the disease and they use the bathroom. They don't wash their
hands very well, right? Because they don't wash
their hands very well, their hands have some
of the pathogen on them. Then, maybe they go on to touch something, like food or water, and then
you may touch the same stuff, so then maybe you'd have some
of the pathogen on your hands. Then, if you give the
virus access to your mouth, you can get infected.
Once it's in your system, what
exactly is it going to do? Well, let's take a look at
the gastrointestinal tract. Along your gastrointestinal tract, you actually have this
wall that kind of lines it. This wall goes over your
stomach, your small intestines, so on, and so forth. We call this the gastrointestinal wall.
I actually wanna zoom in a
little bit more on this wall. You can see here, there
are many different layers. I wanna focus on this
green layer over here. This layer is called the epithelium.
It contains all the cells
that will be responsible for digesting and absorbing
nutrients and water. The viruses are going to
invade the epithelium. Why don't we zoom in on one of the cells in the epithelium? This is our epithelial cell. It'll perform a lot of
really important functions, like digesting and absorbing.
Let's say this cell encounters a virus. First of all, what is this virus made of? First, we have this kind of
capsid structure over here, and it's really just made out of proteins. Within this capsid, you have
some kind of nucleic acids. This can include DNA or RNA.
That virus really wants to replicate, but it lacks the enzymes
necessary to do this, so how is it going to do that? This cell has all of
the machinery necessary to do just that. It has all the enzymes that
can make more viral protein and more viral nucleic acids, so the virus is actually going to invade this epithelial cell, and in doing so, it's literally going to
hijack it, so you'd have all these enzymes in here. These enzymes will be responsible for synthesizing things
like DNA and proteins, so the virus is going to
make use of those enzymes. Now, all of a sudden, you
get all these viral proteins.
You're also gonna get a lot of
viral nucleic acids as well. These are then going to come together, and they're going to form new viruses. The viruses can then leave the cell, then go on to infect
more epithelial cells. Basically, what you have is a
cell that's just been turned into a virus making factory.
In addition to that, the virus is actually going to shut down many of the functions of the epithelial cell. Maybe it'll release some toxins
that can do a lot of damage to the epithelial cell, so, for example, it'll stop the epithelial
cell from absorbing water. It can also deactivate certain proteins on the intestinal gut
lining that are responsible for digesting your food. All in all, it really
stops the epithelial cell from doing what it needs to do, and it just turns it into
a virus making factory.
Let's say that you have
viral gastroenteritis and you want to visit the doctor. What might the doctor do? They might order a few stool samples, just to evaluate whether or
not the pathogen is a virus, because, remember that the feces are contaminated with the pathogen. They could also run a few blood tests, mostly just to see if
the person is dehydrated. The way to see that is if
the person has high levels of sodium or creatinine in their blood.
Once the doctor has
completed all these tests and they've confirmed that you
have viral gastroenteritis, what can you do? Usually, the symptoms last from a few days to about a week, so there
really isn't much medication that people can take if they
have viral gastroenteritis. Antibiotics will not actually
be helpful in this case because they only target bacteria. They do not target viruses. Because of that, it's not really useful to give the person antibiotics.
However, if you wanna
treat those symptoms, one of the best things you could do is drink a lot of fluids. Drink a lot of water,
drink a lot of fluids with salt and sugar in
them, to really overcome a lot of that dehydration
that you may encounter. These are some pretty
significant ways to diagnose and treat viral gastroenteritis. To ensure that you don't get
the virus, the best thing to do is to just practice good hygiene.
Always wash your hands,
always cook food properly, drink decontaminated water,
and so on, and so forth. There's actually one
more thing that we can do to potentially prevent
getting gastroenteritis. That would be getting a vaccination. When we give someone a vaccination, we give them a weaker
version of the virus.
This is called a live attenuated virus, so when you inject it into someone, it's not really gonna
cause any of the symptoms. It's pretty weak and it's pretty benign, but what it will do is it'll actually prep the immune system. The immune system may come along, and it'll actually recognize this virus. It basically just says,
"Okay, we've seen this virus, "and now we know what it looks like, "so that when the real thing comes along, "we can stop it right
away, before it starts "to cause any symptoms." One thing to keep in mind is that we have a vaccination available
for the rota virus.
This vaccination is available in a lot of different countries,
so wherever it's available the rota virus isn't
really as much of a problem in those countries. In fact, this vaccination is so important because it saved thousands of lives..