This lesson will talk about what an endemic disease is and how it is different from an epidemic. We’ll also discuss how an epidemic differs from something known as a pandemic. Finally, we’ll look at some examples of each to help solidify these points.
The Spread of Disease
Weather patterns and diseases have a lot in common. You have probably heard how global warming is a huge concern for everyone in the world since deadly tropical diseases will be able to spread farther and farther into once-cooler areas, infecting many more people than ever before.
But, this isn’t the only way by which weather coincides with the spread of disease, as this lesson will point out metaphorically.
What Is an Endemic Disease?
If you are someone who lives in the Gulf Coast region of the U.S., then you are undoubtedly aware of the hurricane season that occurs every single year. It’s a guarantee that there will be hurricanes in those states. Likewise, it’s as much a guarantee that India will have monsoons, Japan will have earthquakes and northern Siberia will be very cold.
These natural patterns and events occur in set parts of the world and are certain to be there on a constant basis when compared to other parts of the world.Likewise, certain diseases are present in a set population of people or geographic region of the world with just as much consistency. When a disease is present in a population or geographic region at consistent levels and periods of time, we term this an endemic disease.For example, the disease malaria is endemic to tropical areas of the world, such as those in South America or Africa. Malaria, however, is not endemic to Antarctica since it’s not present there.
The flu is endemic to a Chicago winter but not summer. And so on.
What Is an Epidemic?
Consistency isn’t the only thing that defines disease, however. Diseases sometimes spread rapidly and grow in the total number of people they affect over a given time and place.
Metaphorically speaking, sometimes the Gulf Coast of the U.S. has a terrible hurricane season where one hurricane after another bombards the Gulf Coast at a far higher frequency than they usually do, meaning we have far more hurricanes that one season than usual.Very similarly, when an outbreak of disease affects a disproportionately higher number of individuals than normal at a given time, we term this an epidemic. Basically, the disease spreads amongst the population far more than it should for a given time and place.This term is also very relative. For example, 1,000 cases of malaria in a tropical nation may not be an epidemic, but 1,000 cases of malaria in Canada would be an epidemic.
That’s because the 1,000 cases of malaria in an endemic tropical area is considered to be a normal, constant amount of cases of malaria for a set period of time. However, since malaria is not endemic to Canada, even a small increase in the number of people affected by malaria in Canada would be considered an epidemic.
What Is a Pandemic?
Finally, we have one last term to go over. We talked about how weather patterns, like endemic diseases, may occur on a consistent basis in certain parts of the world or how unusual increases of a certain weather pattern in an area is akin to an epidemic of a disease.Well, now imagine that the hurricanes that were once confined to the Gulf Coast begin spreading to more than one continent or even the entire world. This would be indicative of something known as a pandemic.
A pandemic is an epidemic that occurs over a wide area, such as multiple continents or the entire world.A great historical example of a pandemic is something known as the ‘1918 flu pandemic,’ also known as the ‘Spanish Flu,’ that spread all over the world and killed upwards of 100 million people.
Why Disease Spreads
Regardless of whether we’re dealing with a pandemic or epidemic, the reason that either one of these occurs is multi-factorial, meaning it depends on a lot of factors. For example, it’s much easier for an epidemic to begin in densely populated areas such as big cities. That’s because it’s much easier to spread germs around when someone is basically sitting on your lap than if they are miles away, such as in sparsely populated areas. The higher the population density, the more likely a disease is going to spread and spread quickly.
Another reason an epidemic may start is because unsanitary conditions abound. If raw, open sewage is running through the city streets, if people have no access to healthcare to prevent diseases by way of proper vaccination, if garbage is lying around for everyone to see, then this will only serve as a breeding ground for the spread of disease.Furthermore, the microbes that cause us to fall ill are partly to blame as well.
If they mutate, or change their genetic information, they may be able to more easily infect us and spread between us. For simplicity’s sake, after a mutation occurs within a microbe, they essentially become a new type of microbe, but our immune system is better able to kill off a microorganism it has encountered before rather than a new one.Therefore, the larger the mutation in a microbe, the smaller the number of people there will be that are immune to it. Then it follows, logically, that if a mutation big enough in something like the flu virus occurs, then very few people anywhere in the world will be able to fight off the virus. This means that more people will fall ill, more people will spread the disease, and the likelihood of an epidemic, or in severe cases a pandemic, will increase.
Hopefully, you never fall victim to a pandemic. But, it wouldn’t hurt to review all of the things we learned so you’ll at least know what one is if it hits you. A pandemic is an epidemic that occurs over a wide area, such as multiple continents or the entire world, whereas an epidemic is an outbreak of disease that affects a disproportionately higher number of individuals than normal at a given time and place.
Finally, when a disease is present in a population or geographic region at consistent levels and periods of time, we term this an endemic disease.
After finishing this lesson, you might have the ability to:
- Define endemic in relation to disease
- Make distinctions between epidemic and pandemic
- Indicate the ways in which an epidemic is relative
- Outline factors that increase the likelihood of disease spreading