Monday, February 2, 2009

Health Care and Viruses

Americans pass viruses around like a bag of chips. Viruses are strange things that straddle the fence between living and non-living, according to MicrobeWorld. On the one hand, if they're floating around in the air or sitting on a doorknob, they're inert. They're about as alive as a rock. But if they come into contact with a suitable plant, animal or bacterial cell, they spring into action. They infect and take over the cell like pirates hijacking a ship. A virus is basically a tiny bundle of genetic material—either DNA or RNA—carried in a shell called the viral coat, or capsid, which is made up of bits of protein called capsomeres. Some viruses have an additional layer around this coat called an envelope. That's basically all there is to viruses.

According to MicrobeWorld, there are thousands of different viruses that come in a variety of shapes. Many are polyhedral , or multi-sided. If you've ever looked closely at a cut gem, like the diamond in an engagement ring, you've seen an example of a polyhedral shape. (Unlike the diamond in a ring, however, a virus does not taper to a point, but is shaped similarly all around.) Other viruses are shaped like spiky ovals or bricks with rounded corners. Some are like skinny sticks while others look like bits of looped string. Some are more complex and shaped like little lunar landing pods. In some viruses, the capsid is covered by a viral envelope made of proteins, lipids and carbohydrates. The envelopes may be studded by spikes made of carbohydrates and proteins that help the virus particles attach to host cells. Outside of a host, viruses are inert, just mere microbial particles drifting aimlessly.

Viruses are found on or in just about every material and environment on Earth from soil to water to air according to MicrobeWorld. They're basically found anywhere there are cells to infect. Viruses have evolved to infect every form of life, from animal to plant and from fungi to bacteria. However, viruses tend to be somewhat picky about what type of cells they infect. Plant viruses are not equipped to infect animal cells, for example, though a certain plant virus could infect a number of related plants. Sometimes, a virus may infect one creature and do no harm, but cause havoc when it gets into a different but closely enough related creature. For example, the Hantavirus is carried by deer mice without much noticeable effect on the rodents. But if Hantavirus gets into a person, it causes a dramatic and frequently deadly disease marked by excessive bleeding. True parasites, viruses are basically little more than molecular syringes moving genetic information from one cell to another. Some viruses enter a host and leave virtually unnoticed. Others cause disease and destroy the host.

Examples of certain viruses are shown below:
--polioviruses
--rhinoviruses (frequent cause of the common "cold")
--noroviruses (frequent cause of outbreaks of gastrointestinal illness — especially in "closed" settings like cruise ships and nursing homes)
--coronaviruses (includes the agent of Severe Acute Respiratory Syndrome (SARS)
--rubella (causes "German" measles)
--yellow fever virus
--West Nile virus
--dengue fever viruses

According to LiveScience.com, some of the most common or best known viruses include the human immunodeficiency virus (HIV), which is the virus that causes AIDS, the herpes simplex virus, which causes cold sores, smallpox, multiple sclerosis, and the human papilloma virus, now believed to be a leading cause of cervical cancer in adult women. The common human cold is also caused by a virus. Since a great deal of mystery still surrounds the origins of most modern viruses, ways to cure these viruses and the diseases they cause are still in the very early stages of development. Even though the smallest viruses are only about one-millionth of an inch long, they live up to their Latin namesake—poison. They are capable of infecting and hijacking a human body, creating health hazards as minor as the common flu and as disastrous as the AIDS epidemic. Viruses prey upon all living organisms, turning them into virus Xerox machines.
Unlike a bacterium or a cell of an animal, a virus lacks the ability to replicate on its own. A virus does contain some genetic information critical for making copies of itself, but it can't get the job done without the help of a cell's duplicating equipment, borrowing enzymes and other molecules to concoct more virus.

Vaccines play a key role in fighting viruses according to LiveScience. Many scientists consider the vaccine the greatest medical breakthrough of the twentieth century. In 1955, Jonas Salk developed the first widely used vaccine, which gave people lifelong immunity to poliovirus. Vaccines jump-start the human immune system by teaching it how to produce protective shields, called antibodies, to battle a specific virus. Each year, millions of Americans roll up their sleeves for a shot of flu immunity. The shots occur annually because, as the flu travels around the globe, it mutates into new strains. Researchers work to stay ahead of the flu, creating new vaccines to combat each year's version. In order to keep up our immunity, we must continue getting shots in the arm.

According to MedTerms.com, researchers have grouped viruses together into several major families, based on their shape, behavior, and other characteristics. These include the herpesviruses, adenoviruses, papovaviruses (papilloma viruses), hepadnaviruses, poxviruses, and parvoviruses among the DNA viruses. On the RNA virus side, major families include the picornaviruses (including the rhinoviruses), calciviruses, paramyxoviruses, orthomyxoviruses, rhabdoviruses, filoviruses, bornaviruses, and retroviruses. There are dozens of smaller virus families within these major classifications. Many viruses are host-specific, causing disease only in humans or specific animals.

Humans are protected in a couple of ways according to information from the University of Kansas. First, if a particular virus infects one or more cells of a given tissue in our body, the infection leads to the synthesis and secretion of substances called interferons. Interferons are proteins and may be designated as alpha, beta, or gamma interferon). These proteins interact with adjacent cells which help adjacent cells become more resistant to infection by the virus. Sometimes, this resistance isn't quite good enough to prevent the spread of the virus to more and more cells, and we begin to feel sick (we are now experiencing a disease caused by the viral infection). The body's immune system takes over and begins to fight the infection by killing the virus on the outside of the cells, and kills the infected cells, too. The killing of the infected cells prevents the spread of the virus, since as was stated above, a virus requires a living cell in order for the virus to be able to replicate. Eventually, the virus will be completely removed, and we'll get over the illness. HIV is an exception to this situation because HIV infects cells of the immune system which are necessary to kill the infected cells. So, although HIV does not itself directly cause the condition known as AIDS, the eventual death of immune cells due to infection with HIV allows other infections to harm a person.

According to NetDoctor.uk, viral infections are both spread in basically the following ways:
--A person with a cold can spread the infection by coughing and/or sneezing.
--Viruses can be passed on by touching or shaking hands with another person.
--Touching food with dirty hands will also allow viruses from the intestine to spread.
--Body fluids such as blood, saliva and semen can contain the infecting organisms; and transmission of such fluids, for example by injection or sexual contact, is important, particularly for viral infections like hepatitis or AIDS.

NetDoctor also reports how to avoid viral infection:
--Wash your hands thoroughly (often one of the best ways to avoid catching a cold).
--Shaking hands with someone who has a cold is risky, so avoid rubbing your eyes or nose afterwards.
--Food should be cooked or cooled down as quickly as possible.
--Vegetables and meat must be stored separately and prepared on separate chopping boards.
--Meat should preferably be served well-done.
--Remember that food with these invisible organisms does not necessarily smell bad.
--Some organisms are killed as the food is cooked, but they can still leave toxic substances that may cause diarrhea and vomiting.
--The use of condoms during sexual intercourse reduces the likelihood of spreading sexually transmitted diseases.

Viruses can't multiply until they are inside the body's cells according to NetDoctor. This is the reason why the treatment of virus infections is usually left up to the patient's own immune system, although it may be hard to accept when the doctor says the only cure is for 'nature to take its course'. The treatment of virus infections such as influenza will usually involve:
--Drinking plenty of water.
--Staying at home. People who go to work or school in this condition not only risk spreading the virus to their colleagues, but also run a higher risk of catching a bacterial infection.
--Taking a painkiller such as acetimenophen or ibuprofen to bring your temperature down.
Vaccines have been developed against most viral diseases. The vaccine gives the body some help in quickly and effectively fighting the virus. An increasing number of antiviral remedies are being developed that prevent the virus multiplying and cause the illness to run its course more quickly. Unfortunately, these remedies can still only be used on very few viruses. Antibiotics have no effect upon viral infections such as colds or flu.

People can use all the common sense health care rules and still be infected with a virus. Unfortunately, this type of "bug" must be treated as soon as you feel that symptoms are evident, and medical treatment is a must. Even with the flu and other types of viruses that are common, you should see your doctor or go to a medical provider right away. Delaying the visit may result in worsening conditions for your health and life. Be careful, and be wise when dealing with viruses.

Until next time. Let me know what you think.

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