- 1 What is Herpes Simplex Virus?
- 2 Herpes Simplex Virus Type 1
- 3 Herpes Simplex Virus Type 2
- 4 Herpes Simplex Virus Symptoms
- 5 Treatment
- 6 Prevention and Vaccines
What is Herpes Simplex Virus?
Herpes Simplex Virus is a virus which causes the infection known as Herpes Simplex. Herpes Simplex Virus belongs to a family of virus called Herpesviridae. It affects human only. This virus is divided into two categories, namely HSV1 and HSV2. The type 1 causes infection above the waist while the type 2 virus causes infection below the waist.
HSV1 is known to cause cold sores while HSV2 leads to genital herpes. Exceptions however exist and both types can cause infection anywhere else in the body.
Picture : Genital Herpes lesions in men and women
Image source: Adam
Herpes Simplex Virus Type 1
It usually causes diseases such as kertaoconjuctivitis, gingivostomatitis, encephalitis and recurrent herpes labialis.
It is a condition of ulceration of cornea and lesion of the conjuctival epithelium. If ulcers occur repeatedly they can lead to scarring and ultimately blindness.
It mainly occurs in the young children. Symptoms include fever, vesicular lesions in the mouth and irritability. The initial disease is more severe and it remains for a considerable period of time. The lesions heal of their own within 2 to 3 weeks.
It is the inflammatory condition of brain tissues. HSV1 is notorious for causing encephalitis. The encephalitis of HSV1 is characterized by a formation of necrotic lesion particularly in the temporal area of the brain. Patient experiences fever, seizures, vomiting and headache. Mental status also gets altered here. The encephalitis of HSV1 has high rate of mortality. Serious neurological sequelae also occur after this infection.
Herpes Simplex Virus Type 2
This virus is known to causes genital herpes, aseptic meningitis and neonatal herpes.
It is a disease in which painful vesicular lesions are produced in the anal and genitals of both male and female. Primary disease is characterized by severe protracted disease. However, asymptomatic infection also occurs in males and females.
This disease due to HSV2 is mild in nature and also settles on its own.
It arises due to contact with vesicular rashes within the birth canal. This virus is shed and can infect the baby during delivery. It can be asymptomatic to severe in nature. It can easily be prevented by recommending caesarean section to the woman with herpes virus.
Neonatal herpes can occur by both type of viruses and both can cause serious sort of infection in neonates. But no congenital abnormalities of significant nature are found to occur with either of the infections.
Important Facts about Herpes Simplex Virus that one should know
Herpes Simplex Virus Symptoms
The symptoms of Herpes Simplex depend on the conditions that affect the body. Painful sores or blisters occur around the affected region. Cold sores over the mouth are caused by the HSV1 and the second virus type HSV2 is more responsible for herpes genital.
Genital herpes are vesicular lesion seen around the anal and the genital area. Fever may also sometimes accompany these lesions. In HSV1 there is lymph nodes enlargement of the neck also taken place. In HSV2 there is enlargement of genital lymph nodes seen.
It’s Mode of Transmission and How It Enters Human Body
- A Herpes Simplex Virus enters the body not through simple skin contact but through mucous membranes. Mucous membranes are present in the eyes, sexual body parts, and mouth. HSV1 is mainly transferred in saliva. HSV1 causes cold sores on the lips, generally spread by kissing or sharing and eating in same utensils during the infection. HSV is transferred by sexual contact. Also, asymptomatic shedding promotes transmission of the both type of infections.
- In some rare cases herpes simplex infection also spreads to other body parts such as eyes and brain. A pregnant mother if infected by herpes genital may pass on the infection to the baby.
- Once the virus enters your body it never leaves, but shows its signs of outbursts occasionally. The only cure that remains for this infection is treating those outbursts. People getting infected by it by their partners may not see the symptoms in their partners as virus may be in its dormant stage, but it successfully makes a human its carrier.
- Most of the infections caused by type 1 virus occur in the childhood and this is evident due to the presence of antibodies to the virus. In contrast, antibodies to type 2 virus does not appear until the age of sexual activity is achieved.
- The herpes simplex virus replicate in the mucous membrane or the skin at the primary site of the infection. It then moves up the neuron and there becomes latent in the ganglion particularly sensory ganglion cells. HSV1 becomes dormant in the trigeminal ganglia while HSV2 in the sacral and lumbar ganglia.
Tests And Diagnostic Confirmation Of Herpes Virus
To detect Herpes Simplex Virus, tests are conducted by examining the sores on the body parts. Other tests include taking samples of blood, urine, spinal fluid or tears. The herpes viral culture test may also be conducted wherein fluids or cells from the blisters are collected onto a cotton swab and put into a culture cup; it is then tested for the herpes infection and gives specific results especially for detecting herpes genital.
When the infection spreads besides the usual spots to other body parts like brain, the Polymerase chain reaction (PCR) test is conducted. In this test the cells or fluids from blisters or blood or the spinal fluid is taken to find the genetic material of the HSV virus.
Other rapid diagnostic tests include enzyme linked immunosorbent assays (ELISA) in which virus-specific glycoproteins are detected. Other rapid test is the Tzanck smear. It is done by taking cells from the skin lesions and staining with the Giemsa stain. If multinucleated giant cells are found, then it confirms the infection by herpes.
Certain serological tests for instant the neutralization test can be employed in making the diagnosis of herpes infection. It is a good test as it detects the rise in antibody titer accurately. But this test is only helpful in primary infection whereas it holds no importance in recurrent infections.
Different anti-viral drugs are prescribed to treat the infection by herpes virus. These include acyclovir which is first line of drug for treating systemic diseases and encephalitis caused by HSV1. It has found to shorten the duration of the disease. This drug is also be given for neonatal infection resulted by HSV2. For treating eye infection caused by the HSV1 some other antiviral drug groups are prescribed such as trifluridine. It is applied topically. Docosanol and penciclovir are good drugs for treating recurrent oropharyngeal herpes as a result of type 1 infection especially in immunodeficient patients. Valacyclovir and famciclovir are also administered to treat genital herpes. These also suppress the recurrences.
- P.S. no drug treatment of the initial infection can prevent recurrence as medicines are devoid of any effect on the latent virus state, but it is found out that prophylactic and long term use of acyclovir, famciclovir and valacyclovir can suppress the clinical recurrence of the infection.
Prevention and Vaccines
- Prevention includes avoiding contact with a person with a known infection.
- Avoid touching the vesicular lesions or ulcers.
- In those women with genital herpes or positive cultures for virus, cesarean section is suggested. It will prevent their babies acquiring neonatal infection.
- No vaccine has been made for herpes virus. Once virus enters the body, it remains there.