The herpes simplex virus, also known as the Human alphaherpesvirus causes herpes, which is a sexually transmitted infection and disease.
It is transmitted by an infected person to his/her partner mainly through sexual contact including oral sex.
Herpes virus is present in the saliva or genital secretions of the infected person even when he or she is asymptomatic (without symptoms).
Since it is transmitted through any close contact, it is one of the most common sexually transmitted infections and stays with you lifelong.
About 67% of the world population under the age of 50 years has herpes. In the United States, about 60 % of the population harbors this virus (both HSV 1 and HSV 2).
Herpes simplex infections undergo periods of latency when the symptoms disappear but the virus lies dormant in your body. These periods are followed by periods of activation of the virus when the symptoms reappear.
The active periods are due to the reactivation of the virus and not due to reinfection. The reactivation could be due to certain physical and emotional events.
Types of herpes viruses
The herpes simplex virus (HSV), which causes herpes is classified into two types referred to as HSV 1 and HSV 2. Although these viruses have similar morphology and a 50 percent similarity in their DNA, they have some clinical and biochemical differences.
Herpes simplex virus type 1 (HSV 1)
HSV 1 is also referred to as oral herpes virus or herpes simplex virus 1
- HSV Type 1 is responsible for oral herpes, the symptoms of which manifests as fever blisters or cold sores in the mouth, gums, on the lips, and areas around the mouth. It can even cause infection of the conjunctiva and cornea of the eye (ocular herpes).
- Though it causes oral herpes, it is also known to cause genital herpes.
- It is transmitted through the saliva or respiratory secretions of the infected person. (for example through kissing).
- The HSV 1virus stays dormant during remission of infection, in the neural ganglia of the trigeminal nerve throughout life. This nerve supplies the area of the face. Though dormant, it is still infective. This is called latent infection.
- Once infected by this virus, it cannot infect you again. However, you can get infected by HSV type 2.
- You can get infected by this type of herpes virus by using the towels or linen of an infected person.
- Infection with this virus is common in childhood in the lower economic class of people where sharing of towels and linens may be the cause and by affectionate kissing of the child due to ignorance.
- HSV type 1 is being linked to the cause of Alzheimer’s disease. Alzheimer’s disease is degeneration of the neurons and synapses of the brain cortex leading to progressive loss of brain function. It is usually terminal.
- Herpetic Whitlow is caused by this type of virus. It is an infection of the fingers, commonly seen in healthcare providers or doctors, or dentists due to the contact of the fingers with the saliva of an infected patient.
Herpes Simplex Virus Type 2 (HSV Type 2)
It is also referred to as genital herpes virus or herpes virus 2.
- HSV Type 2 is responsible for genital herpes, and it commonly infects the genitals and or the anus.
- Symptoms of HSV type 2 include sores and blisters on the genitals and or the anus.
- However, HSV type 2 can also cause oral herpes due to its transmission by oral sex.
- An infected mother transfers HSV type 2 to its newborn. About 60 to 80% of the newborns of herpes-infected mothers acquire herpes even when the mother is asymptomatic during delivery.
- HSV Type 2 stays dormant in the sensory nerve endings of the sacral nerves throughout life and causes recurrent active infections. However, later in life, these infection attacks stop but the virus lives on in the nerves.
- Some experts believe that the herpes virus type 2 is also responsible for cervical cancer.
Signs and symptoms of herpes virus infection
HSV 1 symptoms include blisters or cold sores in the mouth, gums, on the lips, and areas around the mouth
Genital herpes infections often present no symptoms, or the symptoms may be so mild that the person may not notice them. That is why many persons infected with this virus do not know they are infected.
Genital herpes caused by HSV 2 is characterized by one or more genital or anal ulcers. In addition, symptoms often include fever, body aches, and swollen lymph nodes.
These infections are characterized by active and dormant periods. The frequencies differ from person to person, last for years, and tend to decrease over time.
HSV 1 is transmitted through the saliva or respiratory secretions of the infected person. For example, an infected person can transmit it to his/her partner through kissing.
HSV-2 is mostly transmitted during sexual intercourse. It can also spread through direct contact with genital surfaces, skin sores, or fluids of an infected person.
HSV-2 can spread from the skin in the genital or anal area that appears normal and without symptoms.
Rarely, HSV-2 infection can be transmitted from an infected mother to her baby during delivery to cause neonatal herpes.
Complications of herpes infection
- In an HSV-2 infected person, the risk of acquiring HIV infection increases three-fold. HSV-2 is amongst the most common secondary infection in people living with HIV, About 60% to 90% HIV infected persons also have HSV-2.
- From an infected mother, neonatal herpes can rarely occur when an infant is exposed to the herpes virus during delivery.
- The psychosocial impact from recurrent painful infections can lead to distress
Antiviral medications, such as acyclovir, famciclovir, and valacyclovir, are effective and usually prescribed for HSV. These drugs reduce the severity and frequency of symptoms but do not give a complete cure for the infection.
Both the herpes simplex viruses (HSV) types 1 and 2 continue to be the main human microorganisms against which we do not have effective vaccines or other means to control them.
Incidence of herpes virus infection
- This infection has become very widespread and is slated to reach alarming proportions. It is important, therefore, that you indulge in safe sex.
- More than 50 million people in the U.S. are infected with the herpes virus.
- It is estimated that more than 60% of the sexually active population in the U.S. is infected with the herpes virus.
- About half a million new cases are reported every year.
- There is now stability in these figures, probably due to awareness.