This lesson will discuss the different types of viruses that cause viral hepatitis as well as their different characteristics. We will also talk about what kind of harm these viruses bring and how a person can be treated.
A Trip to the Zoo
This lesson will involve a little trip to the zoo. There, we'll look at some animals - insects included - and how their names or features relate to, of all things, viruses. Hopefully that way you'll remember the important characteristics of each virus a bit better and how these viruses affect the liver.
What Is Viral Hepatitis?
The most important thing I want you to know before we head out is that these viruses all cause something known as viral hepatitis, which is the inflammation of the liver due to a virus.
Viral hepatitis can either be acute, meaning sudden and severe in onset, or chronic, meaning it develops over a long period of time. The viruses that spread viral hepatitis may do so by the fecal-oral route, which is a disgusting notion that someone else pooped out the virus and that virus entered the food or water supply which you ended up consuming! They can also spread via things like sexual contact or blood transfusions.
Okay, now that we got the boring stuff out of the way in the classroom, it's time we get on the bus and take our ride to the zoo.
Different Types of Viral Hepatitis
As we pull up to the zoo and buy our tickets, we notice they have a new temporary exhibit on display with all sorts of insects. One of the exhibits is called the A Cute Ant exhibit. We all buy tickets and get going there right away.
The exhibit has a lot of, well, ants crawling about. They're all tiny, short in stature, and very cute. Ants, by the first letter of the word, are representative of the hepatitis A virus. But because they're part of the A Cute Ant exhibit and are short in stature, you can now easily remember the HAV, the hepatitis A virus, causes an acute disease. That is to say, hepatitis caused by HAV is short in duration.
But don't let the name fool you. Just like a cute ant may have a severe sting, so it is that HAV can be quite a severe disease; and just like there are a lot of ants crawling around, HAV is a common cause of hepatitis in the U.S.
After getting scared away from the exhibit by all the biting ants, we rush off so we don't miss the bottlenose dolphin show. There will be all sorts of nifty tricks on display at the pool!
The B and D in bottlenose dolphin stand for HBV and HDV, respectively. As the show starts, one of the dolphin handlers tells us a bit about these dolphins. These cute dolphins can live upwards of several decades, and they are pack animals that depend on one another to live. They're also, thankfully, not endangered yet, so they're more common than other types of dolphins.
All of these facts are clues to help remember the nature of HBV and HDV, as well. HDV depends on HBV for replication. It's like a pack animal that cannot infect a human unless HBV was there first. HBV, like HAV, is another common cause of hepatitis in the U.S. Finally, both HBV and HDV, like cute and long-lived bottlenose dolphins, can be either acute or chronic in nature.
Next, we head off to the famous giant cockroach exhibit no zoo is complete without. These cockroaches produce some scary hissing sounds. There are tons of cockroaches everywhere, and they have been around for literally millions of years! Their abundance, the ability of their species to survive for so long, and their first letter all clue us into the fact that HCV is the most common cause of chronic viral hepatitis in the U.S., but just as a side-note, it can also cause an acute infection.
Last, but certainly not least, we head off to look at some earwigs. Those things are disgusting. But because they live for a short time, about a year or so, we can remember that HEV is an acute disease, just like HAV.
Consequences of Viral Hepatitis
While the trip to the zoo was fun, we need to get back to school to learn some more important stuff. Acute cases of viral hepatitis can damage the liver, and thereby cause fatigue, vomiting, jaundice, and increased levels of bilirubin in the blood, among other things.
Chronic cases of viral hepatitis are in some ways even worse. In long-standing liver disease, cirrhosis, or scarring of the liver, can occur. This messed up liver will be unable to do its job very well, such as the detoxification of your blood, resulting in damage to the rest of your body.
Even worse, long-standing cases of hepatitis have been associated with the development of liver cancer, also known as hepatocellular carcinoma.
Diagnosis and Treatment of Viral Hepatitis
Blood tests can help determine if you have viral hepatitis, and which type.
Acute cases of viral hepatitis are often treated symptomatically - that is to say, treating signs and symptoms like vomiting as opposed to attacking the virus itself. For instance, if dehydration occurs, then logically hydrating the patient would be important.
In chronic cases of hepatitis, the use of antiviral therapy may be effective and important in treating the patient and preventing things like the development of liver cancer. If the liver is severely damaged due to viral hepatitis, a liver transplant may be necessary.
As you can tell, the treatments vary significantly based upon the exact cause and extent of viral hepatitis.
As a review, remember that viral hepatitis is the inflammation of the liver due to a virus.
The viruses that spread viral hepatitis may do so by the fecal-oral route, which is the passage of pathogens in the feces of one host to the oral cavity of another. They can also be spread by sexual contact or blood transfusion.
These viruses may cause no signs at all or may induce everything from vomiting and jaundice to cirrhosis and liver cancer, also known as hepatocellular carcinoma.
For our purposes, remember these general groupings: HAV and HEV are acute in nature, HCV is chronic in nature, and HBV and HDV can either be acute or chronic. Also, don't forget that HDV needs HBV for replication.
Once you have reviewed this video lesson, your expanded knowledge could allow you to:
- Discuss the definition and causes of viral hepatitis
- Name the different types
- Describe the possible consequences of viral hepatitis
- Understand how it is diagnosed and treated