Science Fair Project Encyclopedia
Smallpox (also known by the Latin names Variola or Variola vera) is a highly contagious disease unique to humans. It is caused by two virus variants called Variola major and Variola minor. V. major is the more deadly form, with a typical mortality of 20-40 percent of those infected. The other type, V. minor, only kills 1% of its victims. Many survivors are left blind in one or both eyes from corneal ulcerations, and persistent skin scarring - pockmarks - is nearly universal. Smallpox was responsible for an estimated 300-500 million deaths in the 20th century. As recently as 1967, The World Health Organization (WHO) estimated that 15 million people contracted the disease and that two million died in that year.
After successful vaccination campaigns, the WHO in 1979 declared the eradication of smallpox, though cultures of the virus are kept by the Centers for Disease Control and Prevention (CDC) in the United States and at the Institute of Virus Preparations in Siberia, Russia. Smallpox vaccination was discontinued in most countries in the 1970s as the risks of vaccination include death (~1 per million), among other serious side effects. Nonetheless, after the 2001 anthrax attacks took place in the United States, concerns about smallpox have resurfaced as a possible agent for bioterrorism. As a result, there has been increased concern about the availability of vaccine stocks. Moreover, President George W. Bush has ordered all American military personnel to be vaccinated against smallpox and has implemented a voluntary program for vaccinating emergency medical personnel.
Famous victims of this disease include Ramesses V (see Koplow, p. 11, plus notes), Shunzhi Emperor of China (official history), Mary II of England, Louis XV of France, and Peter II of Russia. Henry VIII's fourth wife, Anne of Cleves, survived the disease but was scarred by it, as was Henry VIII's daughter, Elizabeth I of England in 1562 and Abraham Lincoln in 1863.
After first contacts with Europeans and Africans, the death of a large part of the native population of the New World was caused by Old World diseases. Smallpox was the chief culprit. On at least one occasion, germ warfare was attempted by the British Army under Jeffrey Amherst when two smallpox-infected blankets were deliberately given to representatives of the besieging Delawares Indians during Pontiac's Rebellion in 1763. That Amherst intended to spread the disease to the natives is not doubted by historians; whether or not the attempt succeeded is a matter of debate.[details]
Smallpox is described in the Ayurveda books. Treatment included inoculation with year-old smallpox matter. The inoculators would travel all across India pricking the skin of the arm with a small metal instrument using "variolous matter" taken from pustules produced by the previous year's inoculations. The effectiveness of this system was confirmed by the British doctor J.Z. Holwell in an account to the College of Physicians in London in 1767.
Edward Jenner developed a smallpox vaccine by using cowpox fluid (hence the name vaccination, from the Latin vaca, cow); his first inoculation occurred on May 14, 1796. After independent confirmation, this practice of vaccination against smallpox spread quickly in Europe. The first smallpox vaccination in North America occurred on June 2, 1800. National laws requiring vaccination began appearing as early as 1805. The last case of wild smallpox occurred on September 11th, 1977. One last victim was claimed by the disease in the UK in September 1978, when Janet Parker, a photographer in the University of Birmingham Medical School, contracted the disease and died. A research project on smallpox was being conducted in the building at the time, though the exact route by which Ms. Parker became infected was never fully elucidated.
Transmission is by droplets, and infection in the natural disease will be via the lungs. The incubation period to obvious disease is around 12 days. In the initial growth phase the virus seems to move from cell to cell, but around the 12th day, lysis of many infected cells occurs and the virus will be found in the bloodstream in large numbers. The initial or prodromal symptoms are essentially similar to other viral diseases such as influenza and the common cold - fevers, muscle pain and stomach aches etc. The digestive tract is commonly involved, leading to vomiting. Most cases will be prostrated.
Smallpox virus preferentially attacks skin cells and by days 14-15, smallpox infection becomes obvious. The attack on skin cells causes the characteristic pimples associated with the disease. The pimples tend to erupt first in the mouth, then the arms and the hands, and later the rest of the body. At that point the pimples, called macules, should still be fairly small. This is the stage at which the victim is most contagious.
By days 15-16 the condition worsens and the pimples grow into papules. These then fill up with pus, turning them into pustules. After the appearance of the pustules, the course of the disease can take two vastly different courses. In route A -- if the victim is going to survive the outbreak -- the pustule will deflate in time (the duration is variable), and will start to dry up, usually beginning on day 28. Eventually the pustules will completely dry and start to flake off. Once all of the pustules flake off, the patient is considered cured.
If the patient is going to die, route B, an entirely different set of symptoms starts to develop. First, bleeding will occur under the skin, making the skin look charred and black (this is known as black pox). Soon afterwards, bleeding begins in the organs. Death may occur from bleeding, or from loss of fluid. The entry of other infectious organisms, since the skin and intestine are no longer a barrier, can also lead to multi-organ failure.
During the Peloponnesian War (431-404 BCE), when an Athenian victory still seemed within reach, the city of Athens was hit by a plague. Although historians have long considered this an example of bubonic plague, more recent examination of the reported symptoms lead scholars to believe the disease was either measles or smallpox. Because the Spartans had a much greater army, the Athenians were forced to retreat behind the city walls of Athens. From there, they hoped to keep the Spartans at bay, allowing the Athenian navy to cut off supply lines. The epidemic broke out in the city, which was tightly packed with people. It killed many of Athens's infantry, some expert seamen and their leader, Pericles. Leaderless and weakened, the remaining Athenians fought bravely but were defeated. The loss of the war paved the way for the Macedonians and, ultimately, the Romans. This was smallpox's first recorded role in influencing history, but it would not be the last.
The next major smallpox epidemic occurred in India. The exact date is unknown. In 400 CE, an Indian medical book recorded a disease marked by pustules, saying "the pustules are red, yellow, and white and they are accompanied by burning pain .... the skin seems studded with grains of rice." The Indian epidemic was thought to be punishment from a god, and the survivors created a goddess to honor the disease. In Hinduism there is a goddess named Sitala, who both causes and cures high fever, rashes, hot flashes and pustules. All of these are symptoms of smallpox.
Smallpox did not enter Europe until 581 CE. Most of the details about the epidemic that followed are lost, probably due to the scarcity of written records and the general lack of social order in the European Dark Ages.
In 1519 Hernán Cortés landed on the shores of what is now Mexico and was then the Aztec empire. After he landed, one of the most famous coincidences in history took place. The Aztecs were expecting the arrival of a white-skinned god with yellow hair, Quetzalcoatl. Cortes had yellow hair and white skin and thus was received as a god, and was allowed to rule accordingly. In 1520, another group of Spanish came from Cuba and landed in Mexico. Among them was an African slave who had smallpox. When Cortes heard about the other group, he went and defeated them. In this contact, one of Cortes's men contracted the disease. When Cortes returned to Tenochtitlán, he brought the disease with him.
Soon the Aztecs realized that Cortes was not a god and rose up in rebellion. Outnumbered, the Spanish were forced to flee. In the fighting, the Spanish soldier carrying smallpox died. After the battle, the Aztecs evidently looked on the invaders' bodies for riches and contracted the virus. Cortes would not return to the capitol until August 1521. In the meantime smallpox was devastating the Aztec population. It killed most of the Aztec army, the emperor, and 25% of the overall population. A Spanish priest left this description: "As the Indians did not know the remedy of the disease...they died in heaps, like bedbugs. In many places it happened that everyone in a house died and, as it was impossible to bury the great number of dead, they pulled down the houses over them so that their homes become their tombs." On Cortes' return, he found the Aztec army's chain of command in ruins. The soldiers who lived were still weak from the disease. Cortes then easily defeated the Aztecs and entered Tenochtitlán, where he found that smallpox had killed more Aztecs than had the cannons. The Aztecs said that they could not walk though the streets without stepping on the bodies of smallpox victims.
The effects of smallpox on Tahuantinsuyu (or Inca empire) were even more devastating. Beginning in Colombia, smallpox spread rapidly before the Spanish invaders first arrived in the empire. The spread was probably aided by the efficient Inca road system. Within months, the disease had killed the Sapa Inca Huayna Capac, his successor, and most of the other leaders. Two of his surviving sons warred for power and, after a bloody and costly war, Atahualpa become the new Sapa Inca. As Atahualpa was returning to the capital Cuzco, Francisco Pizarro arrived and through a series of deceits captured the young leader and his best general. Within a few years smallpox claimed between 60% and 90% of the Inca population, with other waves of European disease weakening them further.
Even after the two mighty empires of the Americas were defeated by the virus, smallpox continued its march of death. North America was next. In 1633 in Plymouth, Massachusetts, the Native Americans were struck by the virus. As it had done elsewhere, the virus wiped out entire population groups of Native Americans. It reached Lake Ontario in 1636, and the lands of the Iroquois by 1679, killing millions. The worst sequence of smallpox attacks took place in Boston, Massachusetts. From 1636 to 1698, Boston endured six epidemics. In 1721 the most severe epidemic occurred. The entire population fled the city, bringing the virus to the rest of the 13 colonies. In the late 1770s, during the American Revolutionary War, smallpox returned once more and killed an estimated 125,000 people.
(See: Population_history_of_American_indigenous_peoples for a discussion of this disease and other issues at the time of European contact.)
By that time, a preventive treatment for smallpox had finally arrived. It was a process called inoculation, also known as insufflation or variolation. Inoculation was not a sudden innovation, as some practices had been around for centuries. The Chinese blew powdered smallpox scabs up the noses of the healthy. The patients would then develop a mild case of the disease and from then on were immune to it. The process spread to Turkey, where an American doctor learned of it. He then told the Royal Society in England, where Lady Mary Wortley Montagu learned of it. She began to get other people interested in inoculation. When no one listened, she tried it on her son and daughter, aged 5 and 4 respectively. They both recovered quickly and the procedure was hailed as a success.
In 1721, an epidemic of smallpox hit London and left the British Royal Family in fear. When they read about the success of Lady Wortley Montagu's efforts, they wanted to use inoculation on themselves. Doctors told them that it was a dangerous procedure, so they decided to try it on other people first. The subjects they used were condemned prisoners. The doctors inoculated the prisoners and all of them recovered in a couple of weeks. So assured, the British royal family inoculated themselves and reassured the English people that it was safe.
But inoculation still had its critics. Prominent among them were religious preachers who claimed that smallpox was God's way of punishing people and that inoculation was a tool of Satan. This resistance only encouraged Montagu and the others to work even harder. By 1723 inoculations were extremely common in England.
In 1721, Onesimus (Oh-NES-ih-mus) was the slave of a Boston preacher when smallpox came to Boston via a ship arriving from Barbados.Catalog to the exhibit entitled "TO SLAY THE DEVOURING MONSTER: The Vaccination Experiments of Benjamin Waterhouse" (2000). Hosted by the Rare Books and Special Collections, Francis A. Countway Library of Medicine. Verified availability 2005-03-12.
- Fenn, Elizabeth Anne (2001). Pox Americana: The Great Smallpox Epidemic of 1775-82 (1st edition). Hill and Wang. ISBN 0809078201.
- ^ Willoughby, Brian (Feb 12, 2004). BLACK HISTORY MONTH II: Why Wasn't I Taught That?. Tolerance.org. Availability verified 2005-03-02.
- ^ A Brief Biography of Dr. Louis T. Wright hosted as part of the Great Migration Project. Availability verified 2005-03-03.
- ^ Spotlight on Black Inventors, Scientists, and Engineers hosted by the Department of Computer Science of Georgetown University. Availability verified 2005-03-03.
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