- [Voiceover] Salmonella
poisoning is caused by a bacteria known as Salmonella enterica. It's usually contracted when people just eat plain old bad food. So I don't mean food that
doesn't taste very good. I mean food that hasn't
been cooked properly or hasn't been stored properly or has been contaminated with something containing the bacteria itself. Now, when you eat this kind of food, the bacteria will enter your stomach. Remember that the stomach has
a very acidic environment. As a result, most of the
bacteria will die off. However, some may end up surviving and make their way into
the small intestine. So why don't we look a
little bit more closely at the small intestine itself. Once again, there are
many different layers of the wall of the small intestine. And we'll be focusing on this green layer known as the epithelium. The epithelium contains all of these cells that will be doing the
digesting and absorbing. And it's these cells that
the bacteria will invade. So we can actually zoom in on
one of the cells over here. Once again, this is our epithelial cell. And we have the bacteria over here. Now, this bacteria is pretty interesting because it actually has a whole bunch of different structures
that look like tails. These tails are known as flagella. Flagella is really just
plural for flagellum. These bacteria will use this flagella to move it near the epithelial cell. At this point it then physically attaches to the epithelial cell and then injects a whole bunch
of compounds into that cell. Those compounds will ultimately allow for the internalization of that bacteria. So in other words, that
bacteria will then be able to make this epithelial cell its new home. Now, remember that a lot of bacteria have this structure around
them called the cell wall. And associated with that
cell wall in this case is a chemical called an endotoxin. That endotoxin will trigger the release of chemicals called cytokines. And these cytokines will ultimately lead to a process known as apoptosis, which just basically means cell death. So eventually this
epithelial cell will die off. And now you have all of these cells in the epithelium just dying. And remember that these
cells are responsible for digesting and absorbing food. So now you can't do that anymore. As a result, you may experience
a lot of different symptoms. Now, a like all of the
forms of gastroenteritis or food poisoning, people
will experience some diarrhea. And given that this is
a bacterial infection, people will experience bloody diarrhea. Vomiting and nausea is also common. And because you're constantly expelling the contents in your system, this can lead to dehydration. And finally, because you can't
really absorb water as well, people may experience cramps. Now, these are symptoms that you may see if the bacteria stays in the gut. You may actually see some other symptoms if the bacteria manages
to enter the bloodstream. So for example, you may have a fever. This is typically uncommon, but it's possible for it to happen. And if the person has a condition known as sickle cell anemia, then there's a good
chance that the bacteria could cause a condition
known as ostemyelitis. And this is really just
infection of your bones. Now, typically, the symptoms start about one to three days after exposure. And they'll usually
last for about one week. Now, if you want to be safe,
you can go to the doctor to get a real diagnosis. And like always, what they'll do is they'll take a stool sample. They'll then evaluate the
contents of the stool sample and they'll see if it
has the bacteria in it. If it does, then you have
Salmonella poisoning. If they decide that you
have Salmonella poisoning, the doctor will most likely advise you to drink a lot of fluids. And in some cases they may
even give you some antibiotics. Usually antibiotics will
be given if the situation is pretty extreme or severe. And as always, the best way to prevent getting Salmonella poisoning is by eating clean food
and drinking clean water.