Worldwide rates of either HSV-1 or HSV-2 are between 60% and 95% in adults. HSV-1 is usually acquired during childhood. Rates of both increase as people age. Rates of HSV-1 are between 70% and 80% in populations of low socioeconomic status and 40% to 60% in populations of improved socioeconomic status. An estimated 536 million people worldwide (16% of the population) were infected with HSV-2 as of 2003 with greater rates among women and those in the developing world. Most people with HSV-2 do not realize that they are infected. The name is from Greek: ἕρπης herpēs which means "to creep", referring to spreading blisters. The name does not refer to latency.
HSV-2 is contracted through forms of sexual contact with a person who has HSV-2. An estimated 20 percent of sexually active adults in the United States are infected with HSV-2, according to the American Academy of Dermatology (AAD). HSV-2 infections are spread through contact with a herpes sore. In contrast, most people get HSV-1 from an infected person who is asymptomatic, or does not have sores.
Herpes virus type 3 is also known as varicella-zoster virus which causes chicken pox. This virus can also lead to a recurrent infection called herpes zoster or shingles. It occurs when the virus becomes reactivated after causing chicken pox and infects the skin. So if you have had chicken pox as a child, you may get shingles afterwards. Shingles and chicken pox cause blisters anywhere on the body. They are contagious and can be spread by direct contact with fluid from the blisters.
Diagnosing herpes is made much easier if you present to your clinician at the time that the rash is present and if possible, we can take a sample from that to be sent for Herpes PCR (Polymerase Chain Reaction) studies to confirm the diagnosis. Advanced medical investigative techniques such as this will allow us to differentiate type one from type two herpes regardless of the nature and distribution of the rash.
Research has gone into vaccines for both prevention and treatment of herpes infections. Unsuccessful clinical trials have been conducted for some glycoprotein subunit vaccines. As of 2017, the future pipeline includes several promising replication-incompetent vaccine proposals while two replication-competent (live-attenuated) HSV vaccine are undergoing human testing.
These herpes viruses enter the body through small cuts, abrasions, or breaks in the skin or mucous membranes. The incubation period for herpes simplex infections is about three to six days. Transmission (spread) of the virus is person to person and more likely to occur if blisters or lesions are present. The majority enter after an uninfected person has direct contact with someone carrying the virus (either with or without noticeable lesions). Simply touching an infected person is often the way children get exposed. Adolescents and adults frequently get exposed by skin contact but may get their first exposure by kissing or sexual contact (oral and/or genital contact), especially for HSV-2. Statistical studies suggest that about 80%-90% of people in the U.S. have been exposed to HSV-1 and about 30% have been exposed to HSV-2. Usually, the contagious period continues until lesions heal. Some people (estimated from 30%-50%) occasionally shed herpes virus while having few or no associated symptoms or signs.
The frequency and severity of recurrent outbreaks vary greatly between people. Some individuals' outbreaks can be quite debilitating, with large, painful lesions persisting for several weeks, while others experience only minor itching or burning for a few days. Some evidence indicates genetics play a role in the frequency of cold sore outbreaks. An area of human chromosome 21 that includes six genes has been linked to frequent oral herpes outbreaks. An immunity to the virus is built over time. Most infected individuals experience fewer outbreaks and outbreak symptoms often become less severe. After several years, some people become perpetually asymptomatic and no longer experience outbreaks, though they may still be contagious to others. Immunocompromised individuals may experience longer, more frequent, and more severe episodes. Antiviral medication has been proven to shorten the frequency and duration of outbreaks. Outbreaks may occur at the original site of the infection or in proximity to nerve endings that reach out from the infected ganglia. In the case of a genital infection, sores can appear at the original site of infection or near the base of the spine, the buttocks, or the back of the thighs. HSV-2-infected individuals are at higher risk for acquiring HIV when practicing unprotected sex with HIV-positive persons, in particular during an outbreak with active lesions.
Herpes viruses typically infect the oral or genital mucosa. When herpes affects the mouth, it causes the typical "cold sores," which are painful sores or blisters that form on the lips, mouth, or gums. Prior to the development of the blisters, there may be a prodrome (early symptoms indicating onset of a particular disease) consisting of an itching, burning, or tingling sensation in the affected area. The virus remains dormant in the nervous system throughout life, and this is the reason that cold sores often recur in the same location.
If there is enlargement of the spleen, strenuous physical exercise should be avoided to prevent rupture. With the exception of possible complications, mono is rarely fatal and recovery is complete. Once recovered from the mono, you will usually have lifelong immunity from further infection because the body produces antibodies. If too hasty a departure is made from bed rest, however, a relapse may be experienced.