EPIDEMIC OUTBREAKS: A SHORT WORLD HISTORY
When viruses begin to spread in parts of the world we are closely connected to as Americans, we are kept highly informed by the media. The recent outbreak of Ebola has been highly publicized in order to raise awareness and maximize preventive measures. Increasing public panic is not an intended function of this media attention, but, unfortunately, that can be a result. It is still extremely rare, and is not cause for alarm for the vast majority of Americans.
Ebola was officially identified in 1976. The name is derived from the Ebola River, a river in what was then called Zaire. This region is now the Democratic Republic of Congo, and the river is close to the area where the first outbreak occurred. After several official name changes, it is now officially Zaire ebolavirus, but is commonly called Ebola virus (EBOV). It causes a severe and often fatal hemorrhagic fever in humans and other mammals, and is transferred through bodily fluids.
The media attention surrounding the Ebola virus is warranted and plentiful. All suggested precautions and preventive measures should be taken seriously, and if you have been exposed, and you show signs and symptoms consistent with Ebola, follow the established medical protocol.
The world’s medical history is long and storied with multiple viruses and bacterial infections. Medical historians theorize that viruses began to proliferate about 12,000 years ago when humans began developing more densely populated agricultural communities. This allowed viruses to spread with ease.
There have been many different viruses and bacterial outbreaks that have claimed the lives of millions of humans across recorded history. There is a distinction to be made between an epidemic, which is defined as a widespread occurrence of an infectious disease in a particular community at a particular time. A pandemic is defined as an outbreak that spreads across a whole country, or the entire world.
SMALLPOX: Among the earliest viruses was the smallpox virus. In the 20th century it killed approximately 300 million people, likely more than any other virus. Its major symptoms are a high fever and an extensive bodily rash. This virus initially invades the mucus membranes of the mouth and throat, thus creating contagion from mucus and salivary secretions. In 1798, Edward Jenner introduced the smallpox vaccine. Due to extensive vaccination campaigns in the 19th and 20th centuries, smallpox was declared eradicated by the World Health Organization (WHO) in 1979.
In order of fatalities—highest to lowest, National Geographic has outlined the major epidemics of infectious diseases—not including smallpox—beginning 1500 years ago:
Plague of Justinian:
This bubonic plague outbreak spread throughout the Byzantine Empire in the Mediterranean region. Estimates of the death toll vary widely, but CDC estimates that it eventually killed over 100 million people. The bubonic plague is an infection of the lymphatic system, transmitted by the bite of an infected flea.
The Black Plague is a form of the bubonic plague.
This flu, unlike most influenza epidemics, targeted young, healthy adults. Studies determined it was caused by overreactive immune systems. Children and older adults had weaker immune systems, and were not as heavily affected.
Sixth Cholera pandemic:
Cholera pandemics started in India in the 1800s. Cholera is a bacterial infection of the lower intestine, usually caused by infected water. It causes extreme diarrhea and vomiting, and can cause death for a healthy person in a matter of hours.
Noted to be the first pandemic flu outbreak in the modern connected world.
Hong Kong Flu:
Caused by a strain of the Influenza A virus
Fifth Cholera Pandemic:
Fourth Cholera Pandemic:
Seventh Cholera Pandemic:
Identified as a strain of the H1N1 flu, a combination of bird/swine/human flu strains
Second Cholera Pandemic:
First Cholera Pandemic:
Great Plague of London:
Noted to be the last major epidemic outbreak of the bubonic plague in the Kingdom of England, which is now the United Kingdom.
Typhus Epidemic of 1847:
Typhus symptoms include headache, high fever, cough rash, falling blood
pressure, delirium and death. This outbreak was thought to be caused
by the massive exodus of Irish during the Potato Famine. Also known as
camp fever, ship fever, or famine fever because it proliferates after times
of wars and natural disasters. This epidemic occurred primarily in
Haiti Cholera Epidemic:
2014 EBOLA VIRUS EPIDEMIC IN WEST AFRICA:
Congo Measles Epidemic:
West African Meningitis Outbreak:
Meningitis is an inflammation of the tissues surrounding the brain and
spinal cord. It causes a severe headache and high fever.
Severe Acute Respiratory Syndrome, causing flu-like symptoms.
For all the progress that has been made in the field of epidemiology, the great mystery of the human petri dish remains. Great strides have been made in the what, how, where and when, but the WHY remains.