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Click www.ondix.com to visit our student-to-student file sharing network. SMALLPOX The variola virus causes smallpox. The disease is at least 3000 years old, confirmed in China and India, with a few isolated cases in North Africa. There is no mention in Europe until the 6th century. During the 17th and 18th Centuries smallpox was the most serious infectious disease in The West and accounted for a substantial proportion of deaths, especially among town dwellers. The mortality rate varied regionally, with 10% in Europe and 90% in America. During the 20th Century, there was recognized for the first time a milder form of smallpox called variola minor or alas trim. It had a consistently low mortality rate of the order of 1%. This disease was endemic in Britain until 1935. Still more recently there has been recognized a third form, named East African Smallpox, the mortality rate of which in unvaccinated subjects is about 5%. This has not been recognized as having occurred in The West. The plague had eliminated as much as a third of the European population over a five-year period. Smallpox was never that devastating in Europe, becoming endemic and occasionally out breaking. Widespread resistance reduced the losses to local impacts of about 10%. However, introduction of smallpox to America quite rapidly depleted the population. For example, the Spanish attempted to settle Hispania for sugar cane plantation in 1509. By 1518 every single one of the 2.5 million aboriginals had perished, and the labor population had to be restored with African slaves. Hispania (modern Haiti and the Dominican Republic) were the first site of European contact. Exposure to smallpox during early Spanish attempts to convert the population into plantation slavery exterminated all 3.5 million inhabitants. African slaves replaced them, and this process was repeated throughout the New World for decades. Cortes introduced smallpox in 1520 during his unsuccessful assault on Techotitlan, the Aztec capital, now Mexico City. He had retreated to the coast and was surprised to find no retribution force following. After a few months he sent spies to the capital who reported widespread smallpox, and he returned to conquer the Aztecs in a matter of a few weeks, and established himself as their new god and emperor. The conquest of the continent was very much facilitated by rapid population declines. The history of early settlement was typically one of European settlers moving into an area, fighting aboriginals and over time, finding less and less resistance. The Aztec, Huron, Iroquois, Mohegan and other major nations, with populations in the millions, were reduced to thousands or eliminated altogether, mostly by smallpox. A person infected with smallpox and overtly sick usually transmits the virus face-to-face in a closed dwelling. There is no infectious sub-clinical state. Smallpox is a virus that causes a high fever and a rash that scars the skin. Because of recent events, some government officials believe there may be a risk that smallpox could be used to cause harm. Unlike anthrax, smallpox is contagious, but the smallpox virus does not survive in many environments. Smallpox symptoms begin eight to 18 days after a person has been exposed to the virus, and include: headaches, backaches, high fevers, and vomiting. Also, red spots that may develop on the third day after symptoms appear, especially on the face, arms and legs. The spots then turn into blisters that fill with clear fluid, then pus, and eventually become scabs that fall off after three to four weeks. Smallpox can be spread from person to person through the air and through exchanges of body fluids such as saliva. It also can be spread from clothing, bed linens, and other contaminated areas. A person with smallpox is contagious until the last scab falls off, so doctors can isolate people until their disease is no longer contagious to prevent the spread of the disease. If a person catches Smallpox and lives, they develop immunity to the disease and can never catch it again. Like other crowd diseases, smallpox spreads from urban centers outwards. It then goes into non-immune populations until it eventually reaches areas where the population is too thin to allow it to spread any further. Once smallpox runs out of new host bodies, it dies out. The survivors of smallpox became immune to the disease. In 1796, a doctor named Edward Jenner reported something that he'd observed over the years of his practice in rural England that eventually led to the eradication (end) of smallpox. Jenner was curious as to why milkmaids who came in contact with cows infected with a rash called cowpox didn't seem to get smallpox like everyone else. He noticed that the milkmaids got a similar rash, cowpox, on their hands after touching the cows during milking. Jenner's careful observations led him to conclude that getting this milder form of infection must somehow protect the milkmaids. As an experiment, Jenner then deliberately gave people the mild cowpox infection to protect them against the more dangerous smallpox infection. We now know that Jenner was experimenting with the concept of immunization. That's when the body's natural defense system is stimulated to become more protective against a specific infection because it has been exposed to a similar or weakened version of that infection before. The scientist Louis Pasteur further developed the concept and named it "vaccination," a word derived from the Latin word "vacca," or cow. Interestingly, the first vaccine Pasteur developed was against anthrax. Since the time of Jenner, scientists have developed many types of life-saving vaccinations, including ones against diseases such as polio, measles, diphtheria, and pertussis (whooping cough). Approximately 140,000 vials of vaccine are in storage at the Centers for Disease Control and Prevention, each with doses for 50-60 people, and an additional 50-100 million doses are estimated to exist worldwide. This stock cannot be immediately replenished, since all vaccine production facilities were dismantled after 1980, and renewed vaccine production is estimated to require at least 24-36 months. If any new cases of smallpox are discovered, public health officials can rapidly vaccinate people who may have come in contact with the disease, as well as people who came in contact with those people. If a person has been infected with smallpox, the vaccine can prevent the person from becoming sick or make the symptoms less severe if it's given within a few days. Treatment of smallpox is limited to supportive therapy and antibiotics as required for treating secondary bacterial infections. There are no proven antiviral agents effective in treating smallpox. Though smallpox has not been around in many years, I believe that people should still have some slight concern about smallpox. Because it is still being stored in laboratories in Russia, there is a slight chance someone could get a hold of the virus. In which case, they could spread it to everyone again. I doubt that would ever happen, but the chance is still there. Since the chance is still there, it is good to become well educated about this virus as well as polio and others of its sort. So many of our ancestors have died from this disease and we know virtually nothing about it. Kids today should be forced into researching the diseases in order to learn what the chances of us getting it are, and if we DO get it, how would we know? Teens need to know this specific information to be better educated. By being informed about these viruses, they could further read on about other diseases. I personally am not too afraid of catching smallpox in my lifetime. That is also making the assumption that no terrorist or human is going to get the vials of smallpox to spread around. If that were to happen, at least I would know what was going on and what smallpox could do to me. Keywords: smallpox variola virus causes smallpox disease least years confirmed china india with isolated cases north africa there mention europe until century during centuries smallpox most serious infectious disease west accounted substantial proportion deaths especially among town dwellers mortality rate varied regionally with europe america during century there recognized first time milder form called variola minor alas trim consistently mortality rate order this disease endemic britain until still more recently there been recognized third form named east african mortality rate which unvaccinated subjects about this been recognized having occurred west plague eliminated much third european population over five year period never that devastating europe becoming endemic occasionally breaking widespread resistance reduced losses local impacts about however introduction america quite rapidly depleted population example spanish attempted settle hispania sugar cane plantation every single million aboriginals perished labor population restored with african slaves hispania modern haiti dominican republic were first site european contact exposure during early spanish attempts convert into plantation slavery exterminated million inhabitants african slaves replaced them this process repeated throughout world decades cortes introduced unsuccessful assault techotitlan aztec capital mexico city retreated coast surprised find retribution force following after months sent spies capital reported widespread returned conquer aztecs matter weeks established himself their emperor conquest continent very much facilitated rapid declines history early settlement typically european settlers moving into area fighting aboriginals over time finding less less resistance aztec huron iroquois mohegan other major nations populations millions were reduced thousands eliminated altogether mostly person infected overtly sick usually transmits virus face face closed dwelling infectious clinical state virus that causes high fever rash that scars skin because recent events some government officials believe risk could used cause harm unlike anthrax contagious does survive many environments symptoms begin eight days after person been exposed include headaches backaches high fevers vomiting also spots develop third after symptoms appear especially face arms legs spots then turn into blisters fill clear fluid then eventually become scabs fall three four weeks spread from person through through exchanges body fluids such saliva also spread from clothing linens other contaminated areas contagious until last scab falls doctors isolate people their longer contagious prevent spread catches lives they develop immunity never catch again like other crowd diseases spreads from urban centers outwards then goes immune populations eventually reaches areas where thin allow further once runs host bodies dies survivors became immune doctor named edward jenner reported something observed over years practice rural england eventually eradication jenner curious milkmaids came contact cows infected rash called cowpox didn seem like everyone else noticed milkmaids similar rash cowpox their hands touching cows milking jenner careful observations conclude getting milder form infection must somehow protect milkmaids experiment deliberately gave people mild cowpox infection protect them against more dangerous infection know experimenting concept immunization when body natural defense system stimulated become more protective against specific because exposed similar weakened version before scientist louis pasteur further developed concept named vaccination word derived latin word vacca interestingly first vaccine pasteur developed against anthrax since time scientists have developed many types life saving vaccinations including ones diseases such polio measles diphtheria pertussis whooping cough approximately vials vaccine storage centers control prevention each doses people additional million doses estimated exist worldwide stock cannot immediately replenished since vaccine production facilities were dismantled renewed production estimated require least months cases discovered public health officials rapidly vaccinate have come contact well came those infected prevent becoming sick make symptoms less severe given within days treatment limited supportive therapy antibiotics required treating secondary bacterial infections proven antiviral agents effective treating though around many years believe should still have some slight concern about because still being stored laboratories russia slight chance someone could hold which case they could everyone again doubt would ever happen chance since chance good become well educated well polio others sort ancestors died know virtually nothing kids today should forced researching diseases order learn what chances getting would know teens need specific information better educated being informed these viruses they further read personally afraid catching lifetime also making assumption terrorist human going vials around happen least would what going what Keywords General: Essay, essays, termpaper, term paper, termpapers, term papers, book reports, study, college, thesis, dessertation, test answers, free research, book research, study help, download essay, download term papers