Differences Between Herpes Simplex I And Herpes Simplex II

In the United States, Herpes is a common and easily spread sexually transmitted disease (STD). More than one out of every six people ages 14-49 years old have genital herpes. However, because so many people are infected but do not exhibit any symptoms, this disease is unknowingly spread from person to person through sexual contact. Individuals living with a herpes infection often go undiagnosed and consequently continually contribute to the widespread nature of this disease. Today, an estimated 50-80% of HSV-1 and 20-40% of HSV-2 infected individuals show no signs or symptoms of a Herpes infection, in the United States alone.

Statistics like these should not be ignored. Increased education and awareness of the Herpes Virus as a whole, as well as the specific details regarding the two different strains of Herpes Viruses (Herpes Simplex I and Herpes Simplex II) is critical to reducing the rate of infection through early identification, treatment, and preventative measures. 

What is Herpes?

Herpes is a viral STD that affects the central nervous system. There are two main types of Herpes viruses: Herpes Simplex 1 (HSV-1) and Herpes Simplex 2 (HSV-2). HSV-1 is responsible for oral herpes or cold sores whereas HSV-2 is responsible for genital herpes. Both viral strains are part of the Human Herpes DNA virus family and, once an individual is infected, the symptoms will appear at or near the initial point of contact or infection site. 

The herpes virus will typically lie dormant in the nervous system of the human body.  When the virus is activated, it will move through the central nervous system to the skin at or near the point of contact/infection and will appear as a blister, ulcer or sore. The presence of these lesions due to herpes is called “shedding” and is when an individual is the most contagious/at risk of transmitting the disease. However, the herpes virus can be active and spread without these symptoms and, therefore, the chronic and asymptomatic nature of a herpes infection should be managed more than any individual outbreak.

An “outbreak” or “flare up” of a herpes infection can be triggered by a variety of external or internal elements. These can range from physical or emotional stress, local trauma, fever or illness that result in an overworked immune system, immunosuppressant therapy, exposure to ultraviolet light, or hormonal shifts and imbalances. Overall wellness and support should be a priority for individuals managing a herpes infection. 

The only way to know if you have HSV-1 or HSV-2 is to get tested. STDAware advice counselors are available to speak with you about your testing options.

STDAware provides no-cost consultation and treatment solutions for individuals who test positive for HSV-1 or HSV-2 as well as a list of support groups. 


HSV-1 – Is the most common form of herpes and is highly contagious. Known as Oral/Lip Herpes, it typically presents itself through cold sores and fever blisters around the mouth or on the lips. Tingling, itching or burning sensation in or around the mouth is often reported before the blisters appear. The majority of individuals with HSV-1 will not exhibit these symptoms, but will sometimes have an “outbreak” or “flare up” associated with an illness or circumstance that causes their immune system to be compromised allowing the virus to “activate” within their body. Thus the term “cold sore” or “fever blister.” 

In the past, HSV-1 was not considered an STD. However, while an HSV-1 infection is labeled as “Oral Herpes” because it typically is localized only around the mouth and lips, it is becoming more common to find HSV-1 strains on the genitalia. According to John Hopkins University, 20-30% of herpes infections found on the genitalia, in recent years, are from the HSV-1 strain.  

HSV-1 is transmitted through the transfer of saliva, semen, vaginal fluid or herpes sores and blister fluid, while kissing, sharing drinks or oral sex with an infected partner. It can also be transmitted through any form of skin-to-skin contact with a mucous membrane (meaning that touching a cold sore on your mouth and immediately touching the genitals after could result in an HSV-1 infection of the genitalia). However, most cases of HSV-1 infections on the genitals have a lower rate of symptomatic recurrence or “flare-ups,” than HSV-2. It is important to note that the HSV-1 virus can still be spread in the absence of physical symptoms.


HSV-2 is the STD responsible for the majority of genital herpes infections. It is easily and often unknowingly contracted through semen, vaginal fluid, and any form of skin-to-skin contact with mucous membrane. This virus can be dormant in the human body for long periods of time, without any symptoms. However, when the virus is activated by stress on the body’s immune system, the virus will travel through the nervous system back to the original point of infection. An infected individual can experience painful blisters and lesions, on the genitals, anus and upper thighs. Fever, body aches, swollen lymph nodes, as well as tingling or pain in the genitals, legs, hips, and buttocks are reported shortly before the appearance of blisters. 

In most cases, the first symptomatic outbreak of HSV-2 is the most severe. Any recurrent outbreaks are, generally, less severe in nature and longevity. The rate of recurrence of outbreaks tends to become less frequent over time and with proper management. The fact that the majority of HSV-2 infected individuals often do not know that they are infected and do not show any signs or symptoms and are at risk of transmitting the virus to unknowing sexual partners cannot be overstated. 


HSV-2 less frequently infects the mouth and throat than HSV-1. However, the mouth and throat are lined with mucous membranes that are at risk of infection by HSV-2 and other STDs. If oral sex is performed on an individual with an HSV-2 infection, the risk of spreading the disease is increased if there are any existing cuts or abrasions on or in the mouth, or if the person performing oral sex has a weakened immune system. If an individual contracts HSV-2 during oral sex and then performs oral sex on another partner, that partner is then at risk of contracting HSV-2 from oral sex.

Similarities between HSV-1 and HSV-2

HSV-1 and HSV-2 behave and look the same under the microscope but can behave differently in an infected body. The foundational similarity between the two strains is that both infect the body’s mucous membranes. Once the virus enters the body through these mucous membranes (mouth, throat, genitals, urogenitals, nose, eyes and ears), it will either remain dormant in the nervous system or present itself as a physical sore or lesion at or near the initial point of contact/infection.

A herpes infection can remain “dormant” in the human body for long stretches of time without any signs or symptoms. It has been reported to be asymptomatic in 50-80 percent of the infected population. Individuals with frequent or recurrent “flare-ups” not associated with an acute illness should consider being reviewed for the possibility of having a compromised immune system due to a larger medical issue such as HIV, the deadly virus that leads to AIDS, cancer, cancer treatment, diabetes, or an autoimmune disorder.

Because both strains of herpes can infect and strain individuals without any physical symptoms, the only way to know if you have either type of herpes is to get tested. All sexually active individuals are should be routinely tested for STDs anytime there is a change in sexual partner(s) or habits.


What are the differences in Simplex II and Simplex I?

Virologically, HSV-1 and HSV-2 are almost identical, but there are key differentials that separate each strain from each other. HSV-1 often remains dormant near the base of the neck and causes an outbreak around the mouth or on the face. Whereas HSV-2, The herpes virus will typically lie dormant in a section of nerves located at the base of the spine referred to as the sacral ganglia, causing genital herpes outbreaks. 

Surprisingly, HSV-1 is believed to be riskier than HSV-2. While HSV-1 outbreaks or typically considered much milder than its HSV-2 relative, it has a frightening ability to “jump” to different body parts. HSV-1 infections are usually accompanied by annoying cold sores on the lips and face. However, HSV-1 has the ability to spontaneously manifest (meaning spread and infect without a physical transmission or point of contact) in the eyes, leading to blindness, or to the brain, causing herpes encephalitis (a rare but serious neurological disorder and inflammation of the brain).  Whereas, HSV-2 rarely causes additional or compound medical complications and does not spontaneously spread to other parts of the body.

It is also important to note how the two herpes viruses affect pregnant women. If an infected mother has an HSV-2 infection before pregnancy or contracts it early in the pregnancy, the risk of transmission to the infant is 1%. However, the risk of a mother transmitting herpes to their baby increases 30-50% if the mother contracts an HSV-2 infection during the third trimester due to the mother’s body not having built up enough antibodies to protect the baby.

The asymptomatic nature of HSV-2 should be taken seriously. If there has been a change is sexual partner or habits for a pregnant woman, STD testing should be done to ensure the health of both mother and child.

Pregnant women with an HSV-2 infection should be monitored closely by their prenatal care providers, and if an active flare or outbreak is present at the time of delivery, it is likely that the baby will be born by a cesarean section to avoid passing the infant through an infected vaginal canal. If an infant is infected with herpes at birth, it is called neonatal herpes. It is a very serious condition and can range from rash and blisters on the torso and around the mouth and eyes, difficulty breathing, organ and nervous system failure, seizures and even death. Infants whose infections are caught early can be treated, but the HSV virus will remain in their bodies for the rest of their lives. This condition is referred to as congenital herpes. The risk of infection is not specific to vaginal birth. An HSV-2 infection that is contracted late in the pregnancy has a high risk of infecting the baby in utero. 

It is rare that HSV-1 is passed on to an infant during pregnancy and birth, but the increasing rate of HSV-1 strains being transmitted to the genitals should be taken into account. And infants born to a herpes infected mother can still contract the virus even if no symptoms are present. 

Understanding and staying on top of one’s sexual health is vital to overall well-being and quality of life. Open and honest communication with healthcare providers and sexual partners is a critical component to preventing and managing STDs. 

Testing and Treatment

Depending on the state of an individual’s immune system, symptoms of HSV-1 or HSV-2 may never appear but can continue to infect any sexual partner(s). If one believes he or she has either HSV-1 or HSV-2 it is essential to get tested as quickly as possible. Early diagnosis is crucial to reducing the spread of the disease and adequately managing and treating an infection for the individual’s overall well-being. 

There is no cure for herpes, and it is a lifelong, chronic, viral infection. However, there are effective treatments and management protocols, which can reduce the length and severity of a herpes outbreak. In some cases, proper treatment can completely eliminate outbreaks. However, it is critical to understand that individuals living with a herpes infection can still infect their sexual partners even while their condition is being treated and managed and no visible signs of the infection are present. 

The only way to correctly and effectively treat and manage herpes is by identifying it. Routine STD testing is recommended for anyone who is not in a long-term, mutually monogamous relationship. 

Click here to learn more about the no-cost consultations and prescription services offered by STDAware. 


Pro-active and pre-emptive treatment of herpes and any other STD is the best way to maintain sexual health and long-term relationship satisfaction. While there is no cure for herpes, the length and severity of an active herpes outbreak can be reduced (in some cases eliminated) with proper treatment and management. There are a variety of daily suppressive therapies and antiviral medications that can treat and suppress herpes outbreaks, which also reduces but does not eliminate the risk of transmission to sexual partners.

Individuals who test positive for Herpes will be prescribed medication based on personal medical history and existing medications. Common prescriptions for herpes include acyclovir (Zovirax), famciclovir (Famvir), and valacyclovir (Valtrex). One of these antiviral medications mentioned will typically begin to clear an outbreak with a few days or weeks when used correctly.

With proper care and treatment, there is a 70-80% success in reducing the frequency and severity of herpes outbreaks. Recurrent outbreaks should be treated within one day of physical symptoms appearing, and a medical provider should provide a prescription with instructions on how to begin medication once symptoms appear.

STDAware offers a no-cost medical consultation with one of their in-house physicians for anyone whose test comes back positive for having an HSV-1 or HSV-2 infection. First-time treatment and prescription service may also be provided at no cost (Prescriptions and services may vary by State). Click here to learn more about the medical and consultation services provided by STDAware.

Prevention of Herpes

The best way to avoid a herpes infection is to get tested before engaging in any sexual activity with a new partner. Sexually active individuals, who are not in a long-term, mutually monogamous relationship, are advised to get routine STD tests as part of their regular self-care and management protocol. When entering into any new sexual relationship, it is wise for both parties to be tested for STDs at the same time. Click here to learn more about the full panel and individual STD testing options provided by STDAware.

In a consenting relationship, where it is understood that one or both parties have a herpes infection, it is advisable to avoid any sexual contact (vaginal, anal, oral, manual sex) during an active outbreak of oral or genital herpes. It cannot be overstated that the herpes virus CAN be transmitted even when there are no visible signs or symptoms. Using barrier protection like a condom or dental dam can reduce the risk of contraction and transmission of herpes.

Using protection is another critical aspect of preventing the spread of herpes. Condom use does not guarantee that an STD, such as Herpes, will not be transmitted. A certain measure of risk remains even when condoms are used properly. This is because condoms may not cover all of the areas that are or could become infected. Hence, the risk associated with skin-to-skin transmission of STD’s is reduced but not eliminated. STD’s of this nature are herpes, human papillomavirus [HPV] infection, syphilis, and chancroid. However, condoms do provide significant protection against STDs that are transmitted through the contact of genital fluids. To read more about proper condom use and how to find condoms near you click here.

STDs reported around the world are increasing at a startling rate. And the fact that the clinical instances in consideration are ONLY the ones being reported means that the numbers are even higher than what is published. 

There are estimated millions of undocumented cases of STD infections, unknowingly being spread in an ongoing manner. The importance of routine STD screening to the maintenance of healthy and mature sexual relationships is currently at an all-time high. 

Having open and honest conversations with sexual partners is both an ethical responsibility and a health measure. Depending on the state you live in, failure to disclose certain STDs or STIs can be a criminal offense. In some states, having certain STDs is considered a public health hazard. Even though it may be awkward, once an open discussion has been started between sexual partners, proper measures can be taken to safeguard the health and happiness of both parties.

Summary & Recap

There are two strains of the herpes virus.

  1. HSV-1 most commonly responsible for oral herpes 
  2. HSV-2 most commonly responsible for genital herpes. 

In recent years it is increasingly common to find HSV-1 on the genitals and HSV-2 on the mouth or in the throat.

An estimated 85% of Americans (42 million people) are infected with Herpes but do not know it. Herpes can persist in the human body and continue to be contagious with no visible signs or symptoms. The ability for herpes to be spread without the knowledge of either sexual partner is the leading factor in the widespread nature of this disease today. Herpes can also be passed on from mother to child during pregnancy or childbirth.

The only way to know if you have an STD is to get tested.

Proactive, responsible, and regular STD/STI screening reduces the risk of spreading the disease. All sexually active individuals who are not in a long-term, mutually monogamous relationship should be routinely tested for STDs before engaging in sexual activity with a new partner. 

Take the first step in maintaining your sexual health today.


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