Mouth blisters are more than likely actually canker sores, and canker sores are not contagious, just painful. If however, your blister is actually on your lips and not in your mouth, you may have a cold sore on your mouth, which is very contagious. The cause of cold sores is the herpes simplex 1 virus, and all the herpes viruses are highly contagious.
You can generally tell which type of herpes you have been infected with by the position of the sores on your body. Simplex 1 primarily affects the body above your belt line, while simplex 2 affects the nether region. This is not a tried and true way of determining, because both types have been found in opposite areas than they are normally found in. These are rare occurrences though, and you are pretty safe in assuming that cold sores on your lips are the result of HSV1.When herpes simplex one sees the opportunity to emerge from dormancy it shows what it is made of by planting cold sores on the lip of its host body.
These sores are painful, they are annoying, and frequently people are embarrassed by their presence. There is no reason for embarrassment, you did nothing deliberately that created this problem for you. As a matter of fact your first exposure to herpes was more than likely before the age of seven. That is when the majority of us contract primary herpes stomatitis, and we are from then on plagued by cold sores or fever blisters when we are under un-do stress.
The mouth blisters that are called canker sores are not in any way related to any of the types of herpes. As a matter of fact, you probably have canker sores because you inherited the tendency from one of your parents. They are also brought on by environmental influences like a weakened immune system, but they are primarily an inherited condition.
So you know you cannot get rid of the herpes virus once you have caught it, but did you know that you can lessen your chances of having an outbreak? If you think back to the majority of the times you were plagued by one of these awful blisters, then you will recall something going on in your life at the time that had you stressed out.
Maybe it was an emotionally charged event like a break up, or it could possibly have been an illness, or was it sunburn, or did you drink too much alcohol, and leave your body weakened, and dehydrated? Anything that causes you to be fatigued, run down, or ill, can cause an outbreak of cold sores. Remember the sore is a symptom of the disease, and the disease cannot emerge unless your immune system is otherwise engaged, or you need to provide it with some recharge time.
The human body requires rest to recharge, much like our batteries in our cell phones do. When you run your system down you leave yourself open to viruses, and other invasions.