Cold and Flu
Conditions and Diseases
Swine Flu (H1N1/09)
Ebola Hemorrhagic Fever
Cell Biology (cytology)
HIV and AIDS
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.
How can you protect yourself and others from viruses and flu?
How to avoid the spread of colds, flu, and other viral infections: THE SHORT ANSWER: For the flu, get a vaccination (flu shot or jab). See more below in the longer answer. For other viral infections such as measles, mumps, etc. there are also vaccinations that should be used. To avoid HIV/AIDS, or other viral sexually transmitted diseases and infections, always use a condom. See below for more. For a common cold there are no vaccinations, so you'll need to avoid anyone sick, stay at...
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?
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...
What is the causative organism of seasonal influenza?
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 Cold Sores, Viruses (biological)
What does a cold sore feel like?
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. ...
Can you get the flu twice in the same season?
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...
Asked in Health, Cold and Flu, Viruses (biological)
How long does a cold virus live in your home?
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...
When are you most contagious when you have a cold?
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. ...
What are the steps of the lytic cycle?
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...
Asked in Cold Sores, Viruses (biological)
Is herpes bacterial or viral?
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. ...
How are you most likely to catch a cold from someone else?
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...
How do scientist classify viruses?
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. ...
Can you get the flu shot when wheezing?
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...
Asked in Food Safety, Viruses (biological)
A virus of particular concern to food safety is?
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?
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...
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?
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...
Asked in Biology, Ecosystems, Viruses (biological)
Why are viruses not considered living things?
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...
Why do dogs not catch your cold?
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...
Can you get the flu vaccine if you have diarrhea?
It is better to wait until you are over symptoms like that. Several reasons come to mind. If you are ill, you need to be home, resting, drinking fluids, and getting better. If you are ill, and if you have a fever, they won't give you the vaccination. If you are ill you could be infecting many many people by being out in public spreading the germs. ...