There are eight types of herpes that infect humans, collectively known as human herpesviruses (HHV-1 through HHV-8). Most people only think of cold sores or genital herpes, but the herpes family also includes the viruses behind chickenpox, mono, and several other conditions. All eight share one defining trait: once you’re infected, the virus stays in your body for life, lying dormant in cells and potentially reactivating later.
HSV-1: Oral Herpes
Herpes simplex virus type 1 (HSV-1) is the most widespread of all human herpesviruses. It mostly spreads through oral contact and causes infections in or around the mouth, commonly called cold sores. Transmission happens through contact with sores, saliva, or skin surfaces around the mouth. Less commonly, HSV-1 can spread to the genital area through oral sex, making it an increasingly recognized cause of genital herpes as well.
Common symptoms include blisters or open sores (ulcers) on or around the lips and mouth. Before an outbreak, many people notice tingling, itching, or burning where the sores are about to appear. A first infection can also bring fever, body aches, sore throat, headache, and swollen lymph nodes. Many people with HSV-1, however, never develop noticeable symptoms and don’t realize they carry the virus.
HSV-2: Genital Herpes
Herpes simplex virus type 2 (HSV-2) spreads through sexual contact and primarily causes genital herpes. It transmits during sex through contact with genital or anal surfaces, skin, sores, or fluids from an infected person. Symptoms typically include bumps, blisters, or open sores around the genitals or anus, and outbreaks tend to recur over time.
The first episode is usually the most severe, often accompanied by fever, body aches, and swollen lymph nodes near the groin. After that initial outbreak, recurrences are generally milder and shorter. Daily antiviral therapy can reduce the frequency of outbreaks by 70% to 80% in people who have frequent recurrences, and it also lowers the risk of transmitting the virus to a partner. Three antiviral medications are approved for managing genital herpes and can be taken either daily as suppressive therapy or at the start of an outbreak to shorten its duration.
How HSV-1 and HSV-2 Are Diagnosed
If you have active blisters or sores, a healthcare provider can take a swab directly from a sore that hasn’t crusted over yet. This gives the most reliable results. If there are no visible sores, a blood test can detect antibodies to determine whether you carry the virus.
VZV: Chickenpox and Shingles
Varicella-zoster virus (VZV), or human herpesvirus 3, is the one behind chickenpox. The first time you’re infected, you get chickenpox, with its characteristic itchy, blistering rash. After recovery, the virus doesn’t leave your body. It goes dormant in nerve cells and can reactivate decades later as shingles, a painful rash that typically appears as a band or strip on one side of the body.
You can’t get chickenpox twice, but anyone who has had it is at risk for shingles later in life. The risk rises with age and with anything that weakens the immune system. Vaccines exist for both chickenpox (routinely given in childhood) and shingles (recommended for adults over 50).
EBV: The Mono Virus
Epstein-Barr virus (EBV), or human herpesvirus 4, is one of the most common viruses in the world. It’s best known as the primary cause of infectious mononucleosis, often called “mono.” The infection is especially common among teenagers and young adults, who tend to develop the most noticeable symptoms: fatigue, fever, inflamed throat, swollen lymph nodes in the neck, an enlarged spleen, and sometimes a rash.
Most people who develop symptoms recover in two to four weeks, though fatigue can linger longer. Many people are infected with EBV during childhood, when symptoms are mild or absent, and they carry the virus without ever knowing it. Like all herpesviruses, EBV remains in the body permanently after infection.
CMV: Cytomegalovirus
Cytomegalovirus (CMV), or human herpesvirus 5, is another extremely common infection that most healthy people never notice. In adults with normal immune systems, CMV rarely causes significant illness. The concern is primarily for two groups: people with weakened immune systems (such as organ transplant recipients or those with HIV) and newborns. When a pregnant person contracts CMV for the first time, the virus can pass to the developing baby and potentially cause hearing loss, vision problems, or developmental delays. CMV is the most common infectious cause of birth defects transmitted during pregnancy.
HHV-6 and HHV-7: Roseola
Human herpesviruses 6 and 7 are closely related and infect nearly everyone during early childhood. HHV-6 (which has two variants, 6A and 6B) is the primary cause of roseola, a very common childhood illness. Roseola typically starts with a few days of high fever, followed by a distinctive pinkish rash that appears as the fever breaks. It almost always resolves on its own and is rarely serious in otherwise healthy children.
HHV-7 can also cause roseola and similar feverish illnesses in young children. Both viruses are so widespread that most adults have been infected with them, usually without any memory of it. In people with severely weakened immune systems, reactivation of HHV-6 can occasionally cause complications, but this is uncommon in the general population.
HHV-8: Kaposi Sarcoma Virus
Human herpesvirus 8, also known as Kaposi sarcoma-associated herpesvirus (KSHV), is the least common of the eight, with an estimated 3% to 7% of the general U.S. population carrying it. Most people infected with HHV-8 have no symptoms at all. The virus becomes a concern primarily in people with weakened immune systems, particularly those with HIV.
HHV-8 is the cause of all forms of Kaposi sarcoma, a cancer that produces painless, darkly pigmented skin lesions that can be flat or raised. It’s also linked to certain rare lymphomas and a condition called multicentric Castleman’s disease, which causes fever, night sweats, widespread lymph node swelling, and inflammation. In people with healthy immune systems, HHV-8 infection almost never progresses to any of these conditions.
What All Eight Types Share
Every human herpesvirus follows the same basic pattern: an initial infection (which may or may not cause symptoms), a retreat into a dormant state inside specific cells, and the potential to reactivate. For HSV-1 and HSV-2, the virus hides in nerve cells near the spine. For VZV, it’s nerve cells along the spinal cord and skull. EBV and CMV persist in immune cells. This lifelong latency is why herpes infections can’t be cured, only managed.
Reactivation doesn’t always mean visible symptoms. All of the herpes simplex viruses can “shed” from the skin or mucous membranes without producing sores, which is one reason these viruses spread so effectively. Outbreaks and reactivation episodes are more likely during periods of stress, illness, or immune suppression, though they can happen without an obvious trigger.