The HSV viruses multiply in the human cell by overtaking and utilizing most of the human cells functions. One of the HSV steps in multiplication is to take control of the human cell's nucleus and alter its structure. The altered nucleus (enlarged and lobulated or multinucleated) is what actually is used to help diagnose herpes simplex infections by microscopic examination. The reason sores appear is because as they mature the many HSV particles rupture the human cell's membrane as they break out of the cell.
^ Nasser M, Fedorowicz Z, Khoshnevisan MH, Shahiri Tabarestani M (October 2008). "Acyclovir for treating primary herpetic gingivostomatitis". The Cochrane Database of Systematic Reviews (4): CD006700. doi:10.1002/14651858.CD006700.pub2. PMID 18843726. (Retracted, see doi:10.1002/14651858.cd006700.pub3. If this is an intentional citation to a retracted paper, please replace {{Retracted}} with {{Retracted|intentional=yes}}.)
Although it's rare, pregnant women can pass on the herpes infection to their child. This can result in a serious and sometimes deadly infection in the baby. That's why taking steps to prevent an outbreak at time of delivery is recommended starting at 34 weeks into the pregnancy. If you have signs of an active viral infection when it's time to deliver, your doctor will likely recommend a cesarean section for delivery.
Genital herpes is passed on by skin-to-skin contact during vaginal, oral or anal sex, or by sharing sex toys. You can get genital herpes even if there are no visible sores or blisters, and once you have the virus, there is no cure. 'Herpes is more likely to be passed on just before, during or straight after an outbreak, as herpes blisters and sores are highly infectious,' says O’Sullivan.
^ McNeil DG. Topical Tenofovir, a Microbicide Effective against HIV, Inhibits Herpes Simplex Virus-2 Replication Archived 2017-04-09 at the Wayback Machine. NY Times. Research article: Andrei G; Lisco A; Vanpouille C; et al. (October 2011). "Topical Tenofovir, a Microbicide Effective against HIV, Inhibits Herpes Simplex Virus-2 Replication". Cell Host. 10 (4): 379–89. doi:10.1016/j.chom.2011.08.015. PMC 3201796. PMID 22018238.
Herpes, whether on the mouth or genitals, is caused by a family of over 70 related viruses. These viral infections cause small, fluid-filled blisters to develop on the skin and mucous membranes. There are actually eight different types of herpes simplex viruses that both children and adults can acquire, but two are by far the most common: HSV-1 and HSV-2.

Do everything possible to prevent spreading it to other people. The virus cannot live long when it is not in contact with the skin, so door handles and towels are not likely to spread it. Do not share your personal belongings, like toothbrushes and combs.  Wash your hands with soap and water often, and immediately if you touch the sores.  This is important so as to minimize the chance of getting ocular herpes (herpes infection of the eye) which is a serious infection. Be especially careful around infants because their immune systems may not be fully developed. Little children often express affection with sloppy wet kisses. This is a common way to spread the herpes virus within the family.
How to get rid of a cold sore The herpes simplex virus that causes cold sores, often on people’s mouths, is highly contagious and a lifelong infection with no cure. Learn about how to treat cold sores when they appear, including anti-viral tablets and creams and home remedies, plus the life cycle of the virus, and how to prevent its spread. Read now
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