The virus that has killed more people in history than other any other disease is small pox. Recently there has been concern as to whether or not a government or terrorist organization could use smallpox as a biological attack. Small pox was completely eradicated from the world in late 1979. There are some samples that were kept in case there was another outbreak.
The first smallpox vaccine was created in 1796 by the English physician Edward Jenner. He studied how milkmaids that were infected with smallpox did not die when they were infected with the virus, they only got sick. Eventually, Jenner infected an eight year old boy with cowpox and then later with smallpox and the boy was immune.
The immune system is responsible for fighting to get rid of the pathogen, but this takes time. A pathogen can multiply more rapidly than the immune system is able to fight it off. Vaccines expose the immune system to a weakened version of the virus, this which allows it to recognize it more easily.
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Types of Vaccines
The first step to creating a vaccine is to use a sterile petri dish in order to collect the virus. You may collect bodily fluids which contain the virus depending on the type. If you already have the virus use a tissue culture to grow brand new viruses.
There are 6 types of vaccines.
The first type is called a similar pathogen vaccine. This type of vaccine is used to help prevent smallpox. Usually vaccines use an altered version of the same virus, this is not the case with similar pathogen vaccines. As the name suggests, they use a similar pathogen to original one. For example, smallpox vaccines are created using cowpox, a similar pathogen.
The second type of vaccine is called an attenuated vaccine. In this kind of vaccine the virus is altered slighlty. It must be similar enough that it still stimulates an imunne response, but different enough that it doesn't cause the disease that is trying to be prevented. An example of virus that is used in this way is the measles virus.
A killed vaccine is a vaccine where a virus has lost its ability to reproduce but hold all other characteristics, especially the ones that allow it to stimulate the immune system. Polio vaccines are made in this way.
Toxoid vaccines condition the immune system to resist a toxin produced by invading organisms. A tetanus shot helps the target and remove toxins that are produced by the Clostridium tetani bacteria.
Subunit vaccines use a small part of the original virus that can still stimulate a response from the immune system. Some vaccines only use a protein coat from a virus. These vaccines are used to protect against Hepatitis B.
The last type of vaccine is the naked-DNA vaccine. These are being made to aid in fighting AIDS. Only a gene is used in this type of vaccine in order to trigger an immune response. Small loops of the disease's DNA enters a cell and becomes part of the cell's DNA. Now the cell can produce proteins according to the gene.
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Vectors of Rabies
Over 55,000 people die from rabies every year, that is one person every 10 minutes. Rabies is caused by a virus that damages the brain. The virus is carried by almost any mammal and is found everywhere except Antarctica. In North America, rabies is carried by raccoons, skunks, foxes, wolves, and bats. Rabies spreads from organism to organism through saliva by biting. The disease affects the nervous system by spreading to the brain and then the rest of the system.
A human infected with rabies will exhibit flu-like symptoms and later fall into a coma. Rabies can be prevented by staying away from wild animals, stray animals, and sick looking animals. Bats are a major carrier for rabies and should never be handled. If bitten, a person needs to wash the wound and see a doctor. Rabies shots are no longer given in the stomach and are no different than a regular shot. They use to be given in the stomach which made them painful but now are given in the arm.
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(Click the link to view a map showing rabies trends worldwide.)
All animals are at risk of being rabid if they have not been vaccinated. Dogs, foxes, raccoons, skunks and bats are known to be the biggest carriers of rabies.
The symptoms of rabies starts out with a fever, aches and pains, and other flu-like symptoms. After a few days hallucinations, tingling around wound, insomnia and salivation can occur. Respiratory problems and heart deterioration follow, ending in coma and eventually death.
Drug Therapy
Source:
http://www.medsafe.govt.nz/profs/datasheet/g/Globalaciclovirtab.htm
The drug acyclovir is an antiviral agent that is used to treat different types of the herpes viruses like chickenpox, shingles, genital herpes and oral herpes. Acyclovir isn't a cure, there are no cures for any of the herpes viruses, but it is used to treat outbreaks and symptoms that are associated with the viruses. The drug can also reduce the severity of future outbreaks. Acyclovir has not shown any carcinogenic side effects but acts as a chromosome mutagen and should not be administered to pregnant women, even thought it frequently is.
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