The name is derived from the Latin word for "spotted" and refers to the raised bumps that appear on the face and body of an infected person. Two clinical forms of smallpox have been described. Variola major is the severe form of smallpox, with a more extensive rash and higher fever. It is also the most common form of smallpox. There are four types of variola major smallpox: ordinary the most frequent ; modified mild and occurring in previously vaccinated persons ; flat; and hemorrhagic.
However, flat and hemorrhagic smallpox, which are uncommon types of smallpox, are usually fatal. Hemorrhagic smallpox has a much shorter incubation period and is likely not to be initially recognized as smallpox when presenting to medical care. Smallpox vaccination also does not provide much protection, if any, against hemorrhagic smallpox. The last known case occurred in the United States in and due to worldwide vaccination programs, this disease has been completely eradicated.
Smallpox is also known as variola. Since the time of ancient Egypt, smallpox has proven to be one of the most devastating diseases to humankind. Widespread smallpox epidemics and huge death tolls fill the pages of our history books. The first smallpox vaccine was created in However, the disease continued to infect and kill people on a widespread basis for another years.
The last known natural case occurred in in Somalia. By , the WHO declared that smallpox had been completely eradicated, although government and health agencies still have stashes of smallpox virus for research purposes. People no longer receive routine smallpox vaccinations.
The smallpox vaccine can have potentially fatal side effects, so only the people who are at high risk of exposure get the vaccine.
Historical accounts show that when someone was infected with the smallpox virus, they had no symptoms for between seven and 17 days. However, once the incubation period or virus development phase was over, the following flu-like symptoms occurred:. These symptoms would go away within two to three days. Then the patient would feel better. However, just as the patient started to feel better, a rash would appear. The rash started on the face and then spread to the hands, forearms, and the main part of the body.
The person would be highly contagious until the rash disappeared. Within two days of appearance, the rash would develop into abscesses that filled with fluid and pus. The abscesses would break open and scab over.
The earliest written description of a disease like smallpox appeared in China in the 4 th century CE Common Era. Early written descriptions also appeared in India in the 7 th century and in Asia Minor in the 10 th century. Historians trace the global spread of smallpox to the growth of civilizations and exploration.
Expanding trade routes over the centuries also led to the spread of the disease. Smallpox was a terrible disease. On average, 3 out of every 10 people who got it died. People who survived usually had scars, which were sometimes severe.
One of the first methods for controlling smallpox was variolation, a process named after the virus that causes smallpox variola virus. During variolation, people who had never had smallpox were exposed to material from smallpox sores pustules by scratching the material into their arm or inhaling it through the nose. After variolation, people usually developed the symptoms associated with smallpox, such as fever and a rash.
However, fewer people died from variolation than if they had acquired smallpox naturally. The basis for vaccination began in when the English doctor Edward Jenner noticed that milkmaids who had gotten cowpox were protected from smallpox. Jenner also knew about variolation and guessed that exposure to cowpox could be used to protect against smallpox.
To test his theory, Dr. Months later, Jenner exposed Phipps several times to variola virus, but Phipps never developed smallpox. Vaccination became widely accepted and gradually replaced the practice of variolation. At some point in the s, the virus used to make the smallpox vaccine changed from cowpox to vaccinia virus. Traces of smallpox pustules found on the head of the year-old mummy of the Pharaoh Ramses V.
Download pdf icon [PDF — 1 page]. Unfortunately, this global eradication campaign suffered from a lack of funds, personnel, and commitment from countries, and a shortage of vaccine donations. Despite their best efforts, smallpox was still widespread in , causing regular outbreaks across South America, Africa, and Asia.
The Intensified Eradication Program began in with a promise of renewed efforts. Laboratories in many countries where smallpox occurred regularly were able to produce more, higher-quality freeze-dried vaccine. Other factors that played an important role in the success of the intensified efforts included the development of the bifurcated needle, the establishment of a case surveillance system, and mass vaccination campaigns.
By the time the Intensified Eradication Program began in , smallpox was already eliminated in North America and Europe Cases were still occurring in South America, Asia, and Africa smallpox was never widespread in Australia.
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