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Video transcript

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 sometimes gastroenteritis can be caused by a bacteria but for the most part it's caused by some kind of virus and there are really many different types of viruses that can do this some examples could include the adenovirus the sapa virus the rotavirus the norovirus and the astral - so a lot of different viruses can cause gastroenteritis and this is really just a handful of them so 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 going to 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 a watery diarrhea but in general this is the pattern to look out for now how does the virus get into your system to begin with it's usually through fecal to oral transmission so 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 and then maybe they go on to touch something like food or water and then you may touch the same stuff right so then maybe have some of the pathogen on your hands and so then if you give the virus access to your mouth then you can get infected so 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 intestine and so on and so forth we call this the gastrointestinal wall I actually want to zoom in a little bit more on this wall you can see here there are many different layers and I want to 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 virus is going to invade the epithelium so why don't we zoom in on one of the cells in the epithelium so this is our epithelial cell it'll perform a lot of really important functions like digesting and absorbing and let's say this cell encounters a virus first of all what does this buyer is made of well first you have this kind of capsid structure over here and it's really just made out of proteins and 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 well this cell has all of the machinery necessary to do just that it has all the enzymes that can make more viral proteins 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 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 and now all of a sudden you get all these viral proteins you're also going to 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 so 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 some toxins right they can do a lot of damage to the epithelial cell so for example it'll stop the epithelial cell from absorbing water you can also deactivate certain proteins on the intestinal gut lining that are responsible for digesting your food so 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 so let's say that you have viral gastroenteritis and you want to visit the doctor what might the doctor do well they might order a few stool samples just to evaluate whether or not the pathogen is of 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 and the way to see that is if the person has high levels of sodium or creatinine in their blood so once the doctor has completed all these tests and they've confirmed that you have viral gastroenteritis what can you do usually the symptoms lasts from a few days to about a week so there isn't really much medication that people can take if they have viral gastroenteritis now antibiotics will not actually be helpful in this case because they only target bacteria they do not target viruses so because of that it's not really useful to give the person antibiotics however if you want to treat those symptoms one of the best things you can do is drink a lot of fluids so 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 so these are some pretty significant ways to diagnose and and treat viral gastroenteritis and 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 but there's actually one more thing that we can do to potentially prevent getting gastroenteritis and that would be getting a vaccination so when we give someone the 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 going to 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 so the immune system may come along and it'll actually recognize this virus and 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 so one thing to keep in mind is that we have a vaccination available for the rotavirus so this vaccination is available in a lot of different countries right so wherever it's available the rotavirus isn't really as much of a problem in those countries in fact this vaccination is so important because it saved thousands of lives