Viruses (biological)

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses display a wide diversity of shapes and sizes, called morphologies. Generally viruses are much smaller than bacteria. Most viruses that have been studied have a diameter between 10 and 300 nanometres.

Asked in Health, Cold and Flu, Infectious Diseases, Viruses (biological)

How can you protect yourself and others from viruses and flu?

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Well there could be llot of ways to protect. You can either be proactive or reactive. Choice is yours! Since I have been associtated with the different businesses in different times. Here's my take on how to protect yourself and other from viruses and flus. First Things Come FIrst. Say you have booked some hotel. The first thing, you should check if the sheets or the mattress cover or the pillow cases are changed or these have been disnfected. As far as I know any renowened hotel will have a substantial hospitality supplier. For example when I was working with the hotel industry in Dubai, I remember we had a hotel and restuarant supplies from Acacia Supply LLC. Those suppliers used to provide us the sheets and complete manual and the procedure on how to keep these disinfected. Same is the case while I was working with the hospital and I have seen that how frequently they used to change the sheets. So I believe that, this enirely depends on us as how we can protect ourselves against such things.
Asked in Conditions and Diseases, Cold and Flu, Swine Flu (H1N1/09), The Difference Between, Viruses (biological)

What is the difference between a cold and the flu?

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They are caused by different viruses and have slightly different symptoms. See related question below for the symptoms of the A-H1N1/09 "Swine Flu". The symptoms of the cold and flu can be hard to differentiate, sometimes not even possible without a specific laboratory test to determine which virus is causing your symptoms. See the related link below for more information on this from US Flu website, Flu.gov. The primary differences are: The flu usually causes a high fever and a cold doesn't cause a fever except in rare circumstance. General aches and pains with the flu are usually present and can be severe, with a cold they are mild. You may feel very fatigued from the flu and this is unusual with a cold. Headaches are much more common with the flu. The usual cold symptoms of stuffy or runny nose, sneezing, and sore throat are only sometimes seen with the flu. A severe cough comes with the flu but is not as severe with a cold. Colds typically begin with a sore throat. Sometimes a mild fever, cough, and/or a stuffy nose are present. It is important to note the difference between a cold and an allergy because of the different treatments associated with each. Cold symptoms can usually be controlled through the use of a decongestant and anti-inflammatory medicine (e.g. Ibuprofen). Fever is not as common in colds as in the flu. Those with colds almost always have fevers under 101 degrees Fahrenheit. There are a few basic kinds of flu viruses but hundreds of cold viruses. Colds are usually milder than the flu. People with colds are more likely to have a runny or stuffy nose. Colds generally do not result in serious health problems, such as pneumonia, bacterial infections, or hospitalizations, whereas this is possible with an infection with a flu virus. FLU LIKELY (>50% chance of these symptoms) fever 102 deg. F (39 deg. C) or higher (can reach up to 107 deg. F (42 deg. C) in extreme cases) dry hacking cough severe runny nose stuffiness chills (happen during fevers when body adjusts thermostat to raise it's set point) headache POSSIBLE (30-50% chance) sore throat RARE (< 30% chance) diarrhea vomiting COLD LIKELY (>50% chance) runny nose stuffiness coughing frequently POSSIBLE (30-50% chance) fever 99 deg. F to 101 deg. F (37.2 deg C to 38.3 deg C.) chills sore throat RARE (<30% chance) gastrointestinal symptoms like diarrhea and vomiting The 'flu - an abbreviation for "influenza" - is a viral infection of the respiratory passages causing fever, severe aching, and catarrh, and often occurring in epidemics. A cold, on the other hand, a common viral infection in which the mucous membrane of the nose and throat becomes inflamed. Influenza (the flu) is usually a more severe illness than the common cold, which is caused by other respiratory viruses. The 'flu typically showcases symptoms including headaches, chills and cough followed rapidly by a fever, appetite loss, muscle aches and tiredness. Cold symptoms are limited to the upper respiratory tract with runny nose, sneezing, watery eyes, and throat irritation.
Asked in Conditions and Diseases, Cold and Flu, Microbiology, Viruses (biological)

What is the causative organism of seasonal influenza?

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The human seasonal flu, as well as other types of human influenza, are caused by three types of viruses: influenza Types A, B, and C. Swine flu is caused by an influenza type A influenzavirus, for example. Type A flu viruses have been the causes of all influenza pandemics to date. Within each type there are mutations and countless numbers of strains and subtypes. The influenza viruses are RNA viruses that come from the family Orthomyxoviridae.
Asked in Microbiology, Genetics, Viruses (biological)

What is the envelope of a virus made of?

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The envelope of a virus is made of a lipid bilayer with proteins embedded in the bilayer.
Asked in Cold Sores, Viruses (biological)

What does a cold sore feel like?

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They can be quite painful. They feel like a combination of a fat lip like you get if you get hit on the lip, and the worst chapped lips you ever had, plus a burn on top of it all. When you smile it can make them crack open and hurt more. They can ooze and feel like blisters.
Asked in Health, Viruses (biological)

Do viruses reproduce through conjugation?

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A virus can't reproduce by itself. It needs a living cell. Once a virus infects another living cell, it will use that cell's mechanisms to reproduce or alter the DNA.
Asked in Cold and Flu, Infectious Diseases, Swine Flu (H1N1/09), Viruses (biological)

Can you get the flu twice in the same season?

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Catching Flu Twice in a Season Yes, you can. But, it would have to be a different strain or type of the influenza-virus than you previously had (if you are otherwise healthy and have a well-functioning immune system). You would need to be exposed to a different flu virus to get it a second time because your body will have created antibodies to destroy that particular flu virus the first time you had it, and a second exposure that soon should not be able to reinfect you for that reason. There is some eventual loss of protection over the long term possible but not within the same season. Even after receiving the flu vaccine you can get the flu if you are exposed to a different type of flu virus than was in the vaccine, if your immune system is not functioning properly, or if you are exposed before the vaccine was able to create the proper antibodies from the vaccination (usually 2 weeks after the vaccination in most adults and longer in children - up to a month) . The flu vaccine is made with the viral particles of the top 3 flu virus strains that are expected to be circulating in that upcoming season for which the vaccine was developed. US CDC scientists determine each year what viruses should be in the following year's vaccine based on what viruses are circulating in Asia, since these will be moving west toward the US during the flu season. There are many strains, if the scientists do not predict the correct ones, you may still become ill despite a vaccination. You CANNOT get the flu from the flu vaccines. The viruses in the vaccines are killed (inactivated) or weakened, so you cannot get the flu from a flu vaccination. You can check out the NIH's website for more info.
Asked in Health, Cold and Flu, Viruses (biological)

How long does a cold virus live in your home?

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It can last up to 2 weeks. The length of time that cold or flu germs can survive outside the body on an environmental surface, such as a doorknob, varies greatly. But the suspected range is from a few seconds to 48 hours - depending on the specific virus and the type of surface. Flu viruses tend to live longer on surfaces than cold viruses do. Also, it's generally believed that cold and flu viruses live longer on nonporous surfaces - such as plastic, metal or wood - than they do on porous surfaces - such as fabrics, skin or paper.
Asked in Rhinoceroses, Viruses (biological)

What are symptoms for rhino virus?

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Rhinovirus is a fancy phrase/word for the common cold, therefore you most likely already know the symptoms.
Asked by Susan Gutkowski in Viruses (biological), Health

What is the coronavirus?

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The coronaviruses are a family of viruses whose symptoms can range from the common cold to something more serious and potentially lethal, such as severe acute respiratory syndrome (SARS). There are currently no vaccines or antiviral treatments available. In January 2020, an outbreak of the virus occurred in Wuhan, China. So far, over a dozen other countries, including Thailand, Japan, Taiwan, and the United States, have confirmed cases of the infection. A quarantine was issued in Wuhan, and train stations, ferries, and the airport were shut down.
Asked in Cold and Flu, Infectious Diseases, Viruses (biological)

When are you most contagious when you have a cold?

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Adults are contagious one or two days before symptoms of the common cold start and approximately a week after. Children can be contagious even longer, as much as two weeks after symptoms have started. You are most contagious earlier in your illness rather than later. Some people can be infected with a common cold virus and have no symptoms, but still spread the virus to others. See the related links section below for a link to more information.
Asked in Biology, Protists, Bacteria, Viruses (biological)

What enzyme protein is used to copy DNA?

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The enzyme DNA polymerase is what facilitates the replication of DNA, however there are multiple enzymes that aid the process of DNA replication such as helicase, ligase, and exonuclease.
Asked in Cold and Flu, Viruses (biological), Cell Biology (cytology)

What are the steps of the lytic cycle?

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The lytic cycle is one of the two cycles of viral reproduction, the other being the lysogenic cycle. These cycles should not, however, be seen as separate, but rather as somewhat interchangeable. The lytic cycle is typically considered the main method of viral replication, and it results in the immediate destruction of the infected cell. A generalized scheme is presented here. There are variations in the process depending on the type of virus (its genome) and the type of host (bacteria or plant cells or animal cells). The six steps of the lytic cycle operative in viral pathogenesis can be summarized as follows: The virus finds a host cell/ Contact (or initial infection): Viruses require a host to replicate. To infect a cell, the virion links on to a specific region (like a receptor or a glycoprotein) on the surface of the host cell. Viruses do so by either attaching to a receptor on the cell's surface or by simple mechanical force. The virus enters the cell/ Injection (or in some cases the virus' genes are injected into the cell while the virion remains outside the cell): Once a virus attaches, it enters the cell through the plasma membrane and (if present) the cell wall. The virus then releases its genetic material (either single- or double-stranded DNA or RNA) into the cell. In doing this, the cell is infected and can also be targeted by the immune system. The virus takes over the host cell/Integration: The viral genetic material integrates with the host genetic material and uses it to express viral genes instead of the usual cell function. In other words, the virus hijacks the gene expression machinery of the host. Technically, the virus' nucleic acid uses the host cell's machinery to make large amounts of viral components. In the case of DNA viruses, the DNA transcribes itself into messenger RNA (mRNA) molecules that are then used to direct the cell's ribosomes. One of the first polypeptides to be translated is one that destroys the host cell's DNA. In retroviruses (which inject an RNA strand), a unique enzyme called reverse transcriptase transcribes the viral RNA into DNA, which is then transcribed again into mRNA. Biosynthesis/ Viral gene expression: Viral genes are expressed and parts (building blocks) of new virions are formed. After many copies of viral components are made, they are ready to be assembled into complete virus particles. The genes from the virus turn the cell into a virus factory/ Packaging and maturation: Copies of the viral genetic material are packaged into the newly formed virions and the parts are assembled to form many new complete virus particles. The new viruses break out and find a new host to repeat the process/ Lysis and infection: Once new complete virions are fully formed, the production of an enzyme that breaks down the cell wall and allows fluid to enter is begun. The cell eventually becomes filled with typically 100-200 virions and liquid. It then bursts open, which is called host cell lysis. This is how the lytic cycle got its name. Once the host cell is lysed, a huge number of new viruses are released into the inter cellular spaces of the host. The new viruses are then free to attach to and infect other cells in the same host, or to shed from the first host and infect others. This process repeats cell by cell and host by host. Note about a "Lytic" cycle without lysis: Some viruses escape the host cell without bursting the cell membrane. Instead, they bud off from it by taking a portion of the membrane with them to package the new virion. Eventually the host cell's membrane can be totally used up in the budding process, so it is ultimately destroyed by this other mechanism, just as host cells that are destroyed by lysis. Hepatitis C viruses presumably use this method.
Asked in Cold Sores, Viruses (biological)

Is herpes bacterial or viral?

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Herpes simplex viruses type 1 (HSV-1) or type 2 (HSV-2). Most genital herpes is caused by HSV-2. Herpes simples virus 2 infections are the primary cause of gential herpes infections that occur in the genital regions. These form the virus lies dormant in the sacral nerve at the base of the spine.
Asked in Biology, Microbiology, Viruses (biological)

Are viruses harmful or beneficial?

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Some viruses are beneficial in that they have commercial uses. Examples are tulips with streaks of color. Other viruses cause diseases such as colds, HIV.
Asked in Conditions and Diseases, Cold and Flu, Viruses (biological)

How are you most likely to catch a cold from someone else?

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Colds are spread when germs enter the body through a moist body surface, typically the eyes, nose, and mouth. Some transfer of fluid between an infected person and a healthy person (e.g. a sneeze, a kiss, a shared beverage) can spread a cold. Also, a person with a cold can contaminate a surface such as a doorknob with his hands. If a healthy person touches that contaminated doorknob and then rubs his eyes or nose or eats with his hands, he can get the cold. For this reason, regular and thorough hand washing is recommended especially during cold and flu seasons. Colds can be spread by one that is sick breathing on another who is not sick. If the other person breathes in the sickness there is a chance that the healthy person will get sick. Sneezing, coughing, touching your face and mouth and then shaking hands with people. poor hygiene and spread of infection between humans Sneezing colds can spread by when u touch or eat something and someone else comes and touch or eat it tyhen that person has the cold in about a week or less sneezing, touching or using the same silverware. they're airborne and also can be caught by touching a foreign object with the germ then touching your face. You can spread the flu by coming to school sick, if you do not wash your hand after using the toilet you have spread over 2,000 germs on your hands. always wash your hands before you eat. Wash your hands after touching money. If you follow these steps you should stay healthy! ALWAYS GET YOUR FLU SHOT! Nasal secretions containing cold viruses contaminate the hands of people with colds as a result of nose blowing, covering sneezes, and touching the nose. Also, cold viruses may contaminate objects and surfaces in the environment of a cold sufferer. people not washing their hands, not catching their snot in their hands when they sneeze. other people touch things that people with colds have touched so that is how they spread. You contract the cold by getting the virus inside your body, simple as that. Mouth, ears, nose, eyes, and cuts are the way that colds are usually contracted. Colds can also be contracted through sexual organs. The reason getting the cold on your hands is bad is because touching any of those vulnerable entrances will spread the virus there immediately. Once a person is infection, the virus likes to wait in their throat in and nasal passages when it comes to spreading. While in their throat, the cold will be spread whenever they cough or exhale. While in their nose, it irritates the walls of the nose and cause more mucus to be produced, giving it a nice little environment to live in and exit the body.
Asked in Conditions and Diseases, Microbiology, Taxonomy, Viruses (biological)

How do scientist classify viruses?

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They are classified by a number of different viral characteristics. These include DNA vs. RNA viruses, single strand (SS) vs. double strand viruses (DS), enveloped vs. non enveloped, or retrovirus. For example the HIV virus is an enveloped single stranded RNA retrovirus.
Asked in Asthma, Cold and Flu, Respiratory System, Viruses (biological)

Can you get the flu shot when wheezing?

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It is usually good to not bombard your immune system with too many things at once, so it is commonly recommended that you not get a flu shot if you have a fever. The fever indicates that your body is already fighting something, and then it is best to wait until your are fever-free to get the vaccination. If you don't have a fever, then you can probably get the vaccination, but tell the clinician who will be giving you the vaccination about your breathing symptoms and they will decide if there is any reason not to give it to you. If your wheezing is severe or you have not yet had it evaluated by a physician, it might be better to also wait to get the flu shot until after you have consulted with a health care professional about the wheeze and then to also ask about getting a flu shot.
Asked in Food Safety, Viruses (biological)

A virus of particular concern to food safety is?

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Food and waterborne viruses contribute to a substantial number of illnesses throughout the world. Among those most commonly known are hepatitis A virus, rotavirus, hepatitis E virus, and noroviruses. This diverse group is transmitted by the fecal-oral route. The name Norovirus is derived from Norwalk virus, which is responsible for 50% of all foodborne outbreaks of gastroenteritis in the United States. See link below for further information.
Asked in Cold and Flu, Viruses (biological)

How long can a cold virus live in the air?

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Life of Cold Virus While In the Air It is important to understand that viruses don't actually live. They are simply DNA or RNA material encased within a protein complex (a virion). They cause damage when they come in contact with a host's cells and are able to attach and take them over to replicate themselves using the host's energy and materials. A more appropriate question might be how long can a virus stay airborne? This can be answered if the size of the specific viral organism is known and how much weight it has to affect the ability of the respiratory droplet containing it to stay afloat on air currents produced by the cough or sneeze. Usually, especially for cold and flu viruses, this is only a matter of seconds and for a diameter of six feet from the person who coughs or sneezes and produces the respiratory droplets, otherwise, they fall from the air to land on surfaces in that approximate 6 foot area. They can remain active (e.g., able to infect someone) for longer on the surfaces and on objects that receive the droplets as they fall from the air. Often, for flu and cold viruses, this is around 48 hours, but does vary as noted above according to the size of the individual virions. See the related questions below for more details.
Asked in Health, Dog Breeds, Dog Behavior, Viruses (biological)

If someone has been fighting the zoster virus for over a year is losing some hearing and sometimes needs oxygen to breath how can you make things better for her?

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It's unusual to have zoster for a year, so I hope she is continuing to see a physician. I'm not sure if you meant that you were concerned all of the problems mentioned above were linked to one another, but I'm assuming you did not. Here are some suggestions: 1. Make sure her pain is under control; zoster, if she truly still has it, can be a very painful condition. Make sure her pain is being addressed by her physician. 2. Hearing loss can come about from different conditions, be it from normal aging, medications, loud noise, etc. See an ENT to be tested to see if the hearing loss is the type that can be helped by hearing aides or if there is anything else that can be done. 3. Make sure that the person you mentioned and everyone around her does not smoke! This is crucial for someone on oxygen especially; it is still amazing to me that someone on oxygen would put a flame up to their mouth--sometimes even at the same time--which can result in explosions. But more importantly, this could certainly cause more damage. 4. Make sure that she is seeing a physician who can take time to address all of the issues (this may mean coming back for multiple appointments).
Asked in Biology, Ecosystems, Viruses (biological)

Why are viruses not considered living things?

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Viruses do not have all of the characteristics of living things. They consist of a protein coat which contains either DNA or RNA. They are not made of cells. They have no cellular structures. They do not require nutrients. They do not have metabolism. They do not grow or develop. They do not reproduce on their own. They must high-jack a living cell, inject it's genetic material, which then takes over the host cell which then becomes a virus factory. Eventually the cell becomes so full of replicated viruses that they burst, releasing the viruses so they can go on to attack other cells. A virus is not considered a living thing because it can't live on its own and has to rely on another animals cells to reproduce. A living organism technically has to be able to survive and reproduce on their own without help from other organisms. They don't use their own energy to grow, make food, take food, or produce waste. Viruses are not considered living organisms because they are not composed of cells (the Cellular Theory of Life). Also, viruses cannot replicate independently - they must infect a living cell before their structure and genetic material can be reproduced and multiplied. However, there is a vigorous ongoing debate about whether or not viruses are living - they do have discrete genetic material that is transmitted from "parent" to "offspring", they can react to the environment by changing what proteins they are expressing and some viruses are extremely complex. One of the main reasons viruses are considered non living is because they cannot replicate by themselves. In order to replicate they must find a host cell and inject DNA into the host cell which disrupts the host cell's normal processes by causing it to make copies of the virus instead of carrying out all its normal processes. Once the viruses have been created inside the host cell, the host cell bursts to release the viruses. This is the same reason it is considered parasitic, since it uses the host cell for its benefit and damages or kills the host cell in the process.
Asked in Cold and Flu, Veterinary Medicine, Viruses (biological)

Why do dogs not catch your cold?

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The common cold in humans is caused by rhinovirus, which is pretty specific to humans. There are other strains of rhinovirus that infect dogs, but those strains don't infect humans. The barrier for this is the type of protein on the surface of the cells of the upper respiratory tract - there are different proteins on human cells than there are on canine cells. The virus is very well adapted to only one species, so a human-adapted rhinovirus can only infect humans while a canine-adapted rhinovirus can only infect dogs.
Asked in Viruses (biological), Ebola Hemorrhagic Fever

How many people die of Ebola per year?

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According to the World Health Organization, there have been about 1,200 deaths since the virus was identified in 1976 until their report in 2008. That works out to about 37.5 deaths per year.
Asked in Chickenpox, Viruses (biological)

What levels of varicella titer are negative?

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Anything lower than 0.91 is a negative result.