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Epidemic Disaster

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Introduction to Epidemic

IVSAT 2024

We have all heard the term epidemic a lot in our lives, not in a very positive light. A disease outbreak that quickly spreads to a large population is referred to as an epidemic. A pandemic is what we call an outbreak that spreads widely. A disease can spread from person to person during an epidemic, or it could be spread to people by a non-human entity, such as an insect or polluted water. Let’s learn more about the causes of an epidemic.

What is an Epidemic?

Throughout human history, numerous terrible epidemics have occurred. About 25 million people were murdered by the plague in Europe in the 1300s. It earned the nickname "Black Death." For the following 300 years or so, there were occasional outbreaks of the plague in European cities. The terrible influenza (flu) pandemic occurred from 1918–19. Around the world, more than 20 million people passed away.

The frequency of epidemics has decreased over time. Better healthcare and cleaner living circumstances have slowed the spread of illnesses. However, cholera and malaria epidemics still occur in various places of the world. AIDS first emerged in the 1980s and spread quickly, particularly in Africa. A flu-like condition known as SARS emerged widespread in 2003. Within a few months, SARS spread from Asia to every continent. A disease known as COVID-19 was caused in 2019 by a novel virus type. In a short period, it also spread over the globe.

Epidemic Study

Epidemic Study

Types of Epidemics

Depending on where the infection comes from and how it spreads, there are several sorts of epidemics.

1. Common Source Outbreaks

Common source outbreaks happen when there is an increase in infection cases following contact with a common dangerous source of infection, such as contaminated food or water, among a group of people.

2. Propagated or Progressive Epidemics

When the sickness spreads from person to person, certain things happen. Infectious agents that spread disease from one host to another can do so directly between individuals, indirectly through vectors (such as mosquitoes in the case of malaria), in water, food, or other environments.

3. Mixed Epidemics

Both shared source and spread epidemic traits are present. Thus, a mixed epidemic may have a common source at first and then spread by transmission. Foodborne infectious organisms are frequently to blame for mixed outbreaks.

Concept of Epidemic

Concept of Epidemic

What are the Causes of Epidemic Disasters?

Infectious illness epidemics are typically brought on by several circumstances, such as:

  • Infections that spread from person to person, from animal to human, via the environment or through other media typically produce disease outbreaks.

  • At certain times of the year, specific epidemics happen. Whooping cough, for instance, occurs in the spring, whereas measles has two epidemics: one in the winter and one in the spring. In winter, influenza, the common cold, and other upper respiratory tract diseases like sore throat are most prevalent.

  • Infected food sources, such as toxic water, and the movement of specific animal populations, like rats or mosquitoes, which can serve as disease vectors, are other factors that affect how epidemics break out.

  • An epidemic often starts when the transmission threshold is reached, and host resistance to either an established pathogen or a newly developing novel pathogen abruptly decreases below that found in the equilibrium state.

  • The nature of the host population changes (For e.g. increased stress or increase in the density of a vector species).

  • Introducing a developing disease to a host population or altering the genetic makeup of the pathogen reservoir (by the movement of the pathogen or host).

The Spread of Pandemic

The Spread of Pandemic


In this article, we have learnt about epidemics, their types and their causes. An epidemic occurs when a disease spreads quickly through a population, affecting many people in a limited amount of time.

Infectious illness epidemics are typically brought on by several circumstances, such as a large change in the local population's environment, an emerging pathogen's arrival, or an unexpected genetic shift in the bacterium pool. Epidemics typically have to do with how illnesses grow. When immunity to a well-known disease or a recently discovered novel disease is suddenly dropped below that observed in the equilibrium time, and the transmission barrier is exceeded, an epidemic may result.

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FAQs on Epidemic Disaster

1. Which illnesses are examples of epidemics?

An epidemic is defined as an unforeseen rise in disease cases in a particular region. Examples of epidemics include smallpox, measles, polio, yellow fever, and smallpox. An epidemic disease doesn't need to be communicable.

2. What signals an epidemic's end?

Epidemics end when the diseases become endemically domesticated and accepted in people's daily lives and routines.

3. Do epidemics qualify as natural disasters?

In an epidemic, even if the virus is naturally occurring, is no more "natural" than disasters brought on by hurricanes, floods, or tsunamis.

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