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A child infected with smallpox
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Smallpox
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(also known by the
Latin names ''Variola'' or ''Variola vera'') is a contagious
Disease unique to humans.
1 Smallpox is caused by either of two
Virus variants named ''Variola major'' and ''Variola minor''. The deadlier form, ''V. major'', has a mortality rate of 30–35%, while ''V. minor'' causes a milder form of disease called ''alastrim'' and kills ~1% of its victims.
2 Long-term side-effects for survivors include the characteristic skin scars. Occasional side effects include blindness due to corneal ulcerations and infertility in male survivors.
Smallpox killed an estimated 60 million
Europe ans, including five reigning European monarchs, in the 18th century alone. Up to 30% of those infected, including 80% of the children under 5 years of age, died from the disease, and one third of the survivors became blind.
3 Edward Jenner and the history of smallpox and vaccination
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.
4 After successful
Vaccination campaigns throughout the 19th and 20th centuries, the WHO certified the eradication of smallpox in 1977.
5 To this day, smallpox is the only human infectious disease to have been completely eradicated from nature.
6
See Also: Smallpox vaccine
Edward Jenner is credited with producing the
Smallpox Vaccine using
Cowpox fluid (hence the word ''vaccination'' is derived from the Latin ''vacca'', cow); his first vaccination occurred on
May 14 ,
1796 . However, the first European recorded as vaccinating against smallpox was
Benjamin Jesty , a farmer. Jesty noted the common knowledge that dairymaids who had previously contracted the less severe cowpox never suffered with smallpox, even after nursing ill family members. During the smallpox outbreak in the summer of 1774, Jesty inoculated his wife and her children. Jesty's wife became ill but recovered with treatment. Vaccination succeeded
Variolation which originated in Asia long before this time and had been imported to Europe.
7
The practice of vaccination against smallpox spread quickly in Europe and then to North America. Prior to Jenner's cowpox vaccine, many New England settlers were inoculated by means of making small incisions in the arms of the healthy patient, scraping a pustule from a smallpox victim, and spreading the pus in the arm incisions. The inoculated patients were often sick for weeks but generally recovered. Prior to 1776, Abigail Adams from Massachusetts wrote to her husband John Adams (then in Congress in Philadelphia) that she was taking their children to Boston to be inoculated, after a severe outbreak near their rural home had killed entire neighboring families. The first smallpox vaccination in North America occurred on
June 2 ,
1800 by Dr. John Clinch in
Trinity ,
Newfoundland .
8 National laws requiring vaccination began appearing as early as
1805 .
The last case of wild smallpox occurred on
October 26 ,
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 Mrs. Parker became infected was never fully elucidated.
Culture s of the virus are kept by the
Centers For Disease Control And Prevention (CDC) in the
United States and at the
State Research Center Of Virology And Biotechnology VECTOR in
Koltsovo ,
Novosibirsk Oblast ,
Russia . Smallpox vaccinations were discontinued in most countries in the
1970s as the morbidity and mortality of vaccination by then exceeded the risk of infection by a disease extinct in the wild. 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,
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.
On September 1, 2007, the
U.S. Food And Drug Administration (FDA) licensed a new
Vaccine ACAM2000 against smallpox which can be produced quickly upon need. Manufactured by Acambis Inc. of
Cambridge ,
England , and Cambridge,
Massachusetts , the U.S. Centers for Disease Control and Prevention stockpiled 192.5 million doses of the new vaccine (derived from the old Dryvax, and made using a pox
Virus Vaccinia ).[http://canadianpress.google.com/article/ALeqM5hbBLzwxu5WsQewlQlwXUVVa7ja0Q Canadian Press, FDA licenses new vaccine against smallpox; can be produced quickly if needed ]
Smallpox is highly contagious, although less so than other infectious diseases. Smallpox is not notably infectious in the
Prodromal period—viral shedding is usually delayed until the appearance of the rash. Smallpox is transmitted primarily through prolonged social contact or direct contact with infected body fluids or contaminated objects (fomites) such as bedding or clothes. Infection in the natural disease will be via the
Lung s. The fact that there has been no recurrence of wild smallpox since its elimination thirty years ago makes the assumptions made at the start of the elimination campaign - that human smallpox carriers do not exist, and that the virus does not exist outside humans - some of the most certain facts in medical science.
Smallpox is a member of the family
Poxviridae , subfamily chordopoxvirinae. The lifecycle of poxviruses is complicated by having multiple infectious forms, with differing mechanisms of cell entry. It is a large virus, with a double stranded DNA genome of about 200
Kilobases , making it more complicated than many
Bacteria .
The incubation period between contraction and the first obvious symptoms of the disease is around 12 days. In the initial growth phase the virus seems to move from cell to cell, but around the 12th day, s,
Muscle pain,
Stomach aches, etc. The digestive tract is commonly involved, leading to
Vomit ing. Most people become prostrated at this stage.
Smallpox virus preferentially attacks skin cells, and by days 12–15, smallpox infection becomes obvious. The attack on skin cells causes the characteristic
Pimple s associated with the disease. The pimples tend to erupt first in the mouth, then on the arms and the hands, and later on the rest of the body. At this point the pimples, called macules, are usually still fairly small. This is the stage at which the victim is most contagious.
By days 15–16 the condition worsens, and at this point the disease can take two very different courses, depending on whether it is ordinary or hemorrhagic smallpox. The most common type is classic ordinary smallpox, in which the pimples grow into vesicles and then fill up with pus, turning them into pustules. Ordinary smallpox generally takes one of two basic courses. In ''discrete'' ordinary smallpox, the pustules stand out on the skin separately. There is a greater chance of surviving this form. In ''confluent'' ordinary smallpox, the blisters merge together into sheets which begin to detach the outer layers of skin from the underlying flesh. This form is usually fatal. If the patient survives the course of the disease, the pustules deflate in time (the duration is variable), and start to dry up, usually beginning on day 28. Eventually the pustules completely dry and start to flake off. Once all of the pustules flake off, the patient is considered cured, and is no longer contagious.
Chickenpox and smallpox can be distinguished in the field via several methods. An examination of the patient's
Palm s and
Sole s is necessary: unlike smallpox, chickenpox does not usually affect the palms and soles. Additionally, chickenpox pustules are of varying size due to variations in the timing of pustule eruption: smallpox pustules are all very nearly the same size since the viral effect progresses more uniformly.
In the other form of ''Variola major'' smallpox, known as hemorrhagic smallpox, a mortality of 96
percent has been reported.
9 An entirely different set of symptoms starts to develop. The skin does not blister, but remains smooth. Instead, bleeding occurs under the skin, making the skin look charred and black (this is known as
Black Pox ). The eyes also haemorrhage, making the whites of the eyes turn deep red (and, if the victim lives long enough, black). At the same time, bleeding begins in the
Organs . Death may occur from bleeding (fatal loss of blood or by other causes such as brain hemorrhage), 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. This form of smallpox occurs in anywhere from 3–25% of fatal cases (depending on the virulence of the smallpox strain).
The historical modes of death are similar to those in burns, with catastrophic losses of fluid, protein and electrolytes beyond the capacity of the body to replace or assimilate, and fulminating
Sepsis , both due to the removal of the barrier between the internal milieu and outside world. Supportive treatments have improved since the last large smallpox epidemics, but it would be grossly optimistic to imagine that, even with a small number of patients, the most intensive modern treatment would ensure survival, even where the damage is predominantly only in the skin. A reduction in the severity of the disease by raising immunity is likely to make a large difference in numbers reaching the threshold of death, and supportive treatment a small one in elevating that threshold.
It is important to note that, while historical
Epidemic s and
Pandemic s are believed by some historians to have been early outbreaks of smallpox, contemporary records are not detailed enough to make a definite diagnosis at this distance.
10 Originally published as ''Princes and Peasants: Smallpox in History'' (1983), ISBN 0-226-35177-7
The
Plague Of Athens devastated the city of
Athens in
430 BC , killing around a third of the population, according to
Thucydides . Historians have long considered this an example of
Bubonic Plague , but more recent examination of the reported symptoms led some scholars to believe the cause may have been
Measles , smallpox,
Typhus , or a
Viral Hemorrhagic Fever (like
Ebola ).
The (
251 –
266 ), was also either smallpox or measles.
The next major epidemic believed to be smallpox occurred in the goddess Sitala both causes and cures high fever, rashes, hot flashes and pustules. All of these are symptoms of smallpox.
Smallpox did not definitively enter
Western Europe until about
581 when Bishop Gregory of Tours provided an eyewitness account that describes the characteristic findings of smallpox. Most of the details about the epidemic that followed are lost, probably due to the scarcity of surviving written records of early medieval society.
After first contacts with
Europeans and
Africans , some believe that the death of 90 to 95 percent of the native population of the
New World was caused by
Old World diseases.
The Story Of... Smallpox It is suspected that smallpox was the chief culprit and responsible for killing nearly all of the native inhabitants of the Americas. For more than two hundred years, this disease affected all new world populations, mostly without intentional European transmission (Excluding the British Settlements), from contact in the early 1500s to until possibly as early as the French and Indian Wars (1754-1767).
14
In
1519 Hernán Cortés landed on the shores of what is now
Mexico and was then the
Aztec empire. In
1520 another group of Spanish came from
Cuba and landed in Mexico. Among them was an African
Slave who had smallpox. When Cortés heard about the other group, he went and defeated them. In this contact, one of Cortés's men contracted the disease. When Cortés returned to
Tenochtitlan , he brought the disease with him.
Soon, the Aztecs rose up in rebellion against Cortés. Outnumbered, the Spanish were forced to flee. In the fighting, the Spanish soldier carrying smallpox died. After the battle, the Aztecs contracted the virus from the invaders' bodies. Cortes would not return to the capital until August in ruins. The soldiers who lived were still weak from the disease. Cortés then easily defeated the Aztecs and entered Tenochtitlán, where he found that smallpox had killed more Aztecs than had the
Cannon s. The Spaniards said that they could not walk through the streets without stepping on the bodies of smallpox victims.
The effects of smallpox on , 1997.
Even after the two mighty empires of the Americas were defeated by the virus, smallpox continued its march of death. In
1633 in
Plymouth, Massachusetts , the
Native American s 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
Thirteen Colonies .
In The Late 1770s , during the American Revolutionary War, smallpox returned once more and killed an estimated 125,000 people.
15 Peter Kalm in his ''“Travels in North America”'', described how in that period, the dying Indian villages became overrun with
Wolves feasting on the corpses and weakened survivors.
16
By that time, a preventive treatment for smallpox had finally arrived. It was a process called or
Variolation . Inoculation was not a sudden innovation, as it is known to have been practiced in
India as early as 1000 BC.
17 The Indians rubbed pus into the skin lesions. The Chinese blew powdered smallpox scabs up the noses of the healthy after discovery, by a Buddhist nun, that this inoculated non-immune people. The patients would then develop a mild case of the disease and from then on were immune to it. This technique is known as variolation and although variolation had a 0.5-2% mortality rate, this was considerably less than the 20-30% mortality rate of the disease itself. The process spread to
Turkey where Lady
Mary Wortley Montagu , wife of the British ambassador, learned of it from Emmanuel Timoni (ca. 1670–1718), a doctor affiliated with the British Embassy in Istanbul. She had the procedure performed on her son and daughter, aged 5 and 4 respectively. They both recovered quickly and the procedure was hailed as a success and reported to the
Royal Society in
England . Timoni, from the
University of
Padova ,
Italy and a member of the Royal Society of London since
1703 , published “an account, or history, of the procuring the smallpox by incision” in December 1713 in the
''Philosophical Transactions'' . His work was published again in 1714 in
Leipzig and was followed by those of Pylarino (1715), Leduc (1722), and Maitland (1722).
In
1721 , an epidemic of smallpox hit London and left the
British Royal Family in fear. Reading 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 test 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, but even scientific opposition (such as the Fellow of the
Royal College Of Physicians Pierce Dod ) continued for some time.
