Smallpox (Variola vera) - Yan Jun Tsui

What is Smallpox?

Smallpox is a viral infectious disease characterized by fluid filled blisters spread on the skin. It is an airborne and highly contagious disease that is only carried by a human. No other animal can get infected or spread it. It is the only disease to be completely wiped out by humans. The World Health Organisation (WHO) has formally certified the eradication of Smallpox in 1979 after the widespread vaccination of the world population. Today, it is not required for anyone to take the smallpox vaccine as there is no known natural cure to this day.
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What Causes it? How is it transmitted?

Smallpox is a highly contagious disease caused by infection of one of the two types of viruses, Variola major and Variola minor. It transmits from an infected person's mucus when it is exhaled and is breathed in by people in close contact with the infected. It is mostly transmitted from one person to another when in face to face contact or in contact to contaminated clothing or bedding.

What are the symptoms? How long do they it last? Is it deadly?

The symptoms of smallpox does not show until 12 days after the infection. at 13 days, the infected shows symptoms not unlike a common cold, fever, headache, nausea and vomiting. at about 16 days, reddish spots will form in the tongue, mouth and throat. About 24 hours later, the characteristic smallpox pimples will appear and will continue to spread for another day until no more will grow. The mortality rate of smallpox depends on the type of smallpox virus that has infected the person. Variola major has a overall death rate of 30 - 35% while Variola minor, being a much weaker virus, has only a 1% mortality rate. Smallpox can also cause blindness in more severe cases and it is estimated that there is around 400 million deaths related to smallpox during the 20th Century alone. Today, due to the total eradication, most of the world population is vulnerable to smallpox, since the worldwide vaccination program as been terminated. So, due to the lack of immunization and the high mortality rate, if smallpox was to be released in the wild, it would have a devastating effect on the world population. Also, the world is currently unprepared for such an incident, since there is very little vaccine left, many of which is unusable. There are also two known places that have existing smallpox virus for research, one in the United States and one in the former Soviet Union. They were both set to be destroyed but were kept when there were concerns to use the virus in the future as a biological weapon for ongoing US defensive research. When the Soviet Union dissolved, there were many concerns about the spread of the virus to other countries.

Can it be cured? If so, how? If not, is there any way that we can at least treat it?

To this day, there is no known cure for smallpox, treatments for smallpox are primarily supportive and only relieve the symptoms, these treatments include wound care and infection control. The smallpox vaccine is also known to reduce the severity, even in some cases, cure it. If the smallpox vaccine is injected within three days of infection, the chances of survival will increase dramatically for most people. If the vaccine is given four to seven days later, it will likely give some protection or lessen the severity. Like Chicken pox, the body will become immune after one infection.


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