Until the 1980s serological tests for antibodies to HSV were rarely useful to diagnosis and not routinely used in clinical practice. The older IgM serologic assay could not differentiate between antibodies generated in response to HSV-1 or HSV-2 infection. However, a glycoprotein G-specific (IgG) HSV test introduced in the 1980s is more than 98% specific at discriminating HSV-1 from HSV-2.
Herpes virus type 4 is also called Epstein-Barr virus. It typically causes infectious mononucleosis, a “kissing” disease. Symptoms include skin rash, fever, sore throat and swollen lymph glands. The virus can be involved in cancers like nasopharyngeal cancer. Herpes virus type 4 is contagious through bodily fluids, including saliva. Kissing, coughing, sneezing, or sharing utensils can make the infection spread.
Herpes virus type 1 (HSV-1) is the cause of cold sores or fever blisters around the mouth. Usually, the sores or blisters can show up on the outside of the mouth or on the lips. But sometimes, they can be inside the mouth, on the face, nose, cheeks or fingers. HSV-1 can also lead to infection of the genitals, called genital herpes. This occurs when you have a cold sore and perform oral sex on another person. HSV-1 infections are highly contagious. Apart from oral-genital contact, they can be spread through skin-to-skin contact. If you come into contact with a person or a thing that carries HSV-1, you will be likely to get it, too. Often, people get HSV-1 from kissing someone with a cold sore or when they share eating utensils, razors, or towels.
As with almost all sexually transmitted infections, women are more susceptible to acquiring genital HSV-2 than men. On an annual basis, without the use of antivirals or condoms, the transmission risk of HSV-2 from infected male to female is about 8–11%. This is believed to be due to the increased exposure of mucosal tissue to potential infection sites. Transmission risk from infected female to male is around 4–5% annually. Suppressive antiviral therapy reduces these risks by 50%. Antivirals also help prevent the development of symptomatic HSV in infection scenarios, meaning the infected partner will be seropositive but symptom-free by about 50%. Condom use also reduces the transmission risk significantly. Condom use is much more effective at preventing male-to-female transmission than vice versa. Previous HSV-1 infection may reduce the risk for acquisition of HSV-2 infection among women by a factor of three, although the one study that states this has a small sample size of 14 transmissions out of 214 couples.
HSV-1 has been proposed as a possible cause of Alzheimer's disease. In the presence of a certain gene variation (APOE-epsilon4 allele carriers), HSV-1 appears to be particularly damaging to the nervous system and increases one's risk of developing Alzheimer's disease. The virus interacts with the components and receptors of lipoproteins, which may lead to its development.
Human herpes virus 1 (HHV1) is also known as herpes simplex virus 1 (HSV1). It is typically the cause of cold sores around the mouth. HHV1 can also lead to infection in the genital area causing genital herpes usually through oral-genital contact, such as during oral sex. HHV1 infections are contagious and are usually spread from skin-to-skin contact with an infected person through small breaks in the skin or mucous membrane. The HHV1 virus is more likely to be spread through things like sharing eating utensils, razors, and towels from a person who has an active lesion.
Herpes of the mouth is a viral infection. The virus HSV-1 may be transmitted by droplet spread – direct contact with saliva or even respiratory droplets. These droplets must make contact with broken skin or the mucous membranes in order to infect a person. The method of spread can involve kissing an infected person or even through touch. It can also be spread through the use of contaminated kitchen utensils. Sexual contact accounts for a small number of cases of HSV-1. Nevertheless it is a consideration when genital lesions are present. HSV-2 on the other hand is usually transmitted through sexual contact.