Cold sores signify you've been infected by the herpes simplex virus, probably HSV-1 (this is the type 1 strain, instead of the type 2 strain, HSV-2, which is generally responsible for genital herpes). The herpes virus currently has no known treatment so once you are infected you've got the virus for life and can never remove it, I'm sorry to say. While, you ought to be aware that there are many herpes vaccines in-the works at the moment that are looking very promising and may be used in the future to vaccinate oral herpes. in addition to people against Cold sores
Herpes on average 'hibernates', as they say, dormant within the sensory nerve cells close to the site of initial infection, that is usually across the mouth but can be quite a few other areas such as the nose, eyes, and finger and toe nails. All through an active period where you will find noticeable sores (cold sores treatment), the herpes virus goes active and replicates very strongly at first glance of your skin, thus causing said cold sore. This active period will on average last between 2 and 21 days, with per week being about average for many people. Mind you, the frequency, length, and severity of outbreaks will decrease over time as you body builds an immunity to herpes, with some people who have been attacked for years or decades going years between outbreaks, although they will never fully end.
Oral herpes is usually carried when there are apparent sores on the person's experience, however the period immediately before and after a cold sore exists is a stage when the person is asymptomatically shedding the virus and is therefore capable of infecting others even though there are no external signs of the condition. This period of asymptomatic shedding frequently lasts about a week, so you must remember the fact you are likely still infected a week before and after you get a chilly sore.
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A cold sore on your nose is no unique whatsoever from the more common cold sore on the mouth or top, and should be treated in precisely the same manner. The best options are prescription anti-virals, such as acyclovir and valacyclovir, in proper combination with an successful home treatment program, such as using benzyl liquor, lysine supplementation in the proper dosage, maintaining the cold sore treatment clean, dry, and drained, etc. I've found through experimentation over time that with the machine I have applying these things, I can often avoid a cold sore before it ever happens by starting treatment when I feel the tell-tale pain of an oncoming episode, and if one occurs I can usually be rid of it inside of 24-48 hours.