What are herpes viruses?
The herpes virus family comprises more than 200 known members. Nine of them can infect humans. The so-called human herpes viruses (HHV) include
- the herpes simplex viruses type 1 and 2,
- the varicella zoster virus,
- the Epstein-Barr virus,
- the cytomegalovirus and
- the human herpes viruses 6A, 6B, 7 and
- Kaposi’s sarcoma-associated herpesvirus 8.
Human herpesvirus 9 (HHV-9) has been less researched to date and there is still no broad scientific consensus on its properties and effects. Herpes viruses can cause a variety of diseases. They are widespread worldwide. Most adults carry one or more of the nine viruses without realizing it.
Possible herpes virus infections in humans are, for example:
- Cold sores (herpesvirus 1 & 2)
- Genital herpes (herpesvirus 1 & 2)
- Chickenpox (varicella zoster virus)
- Shingles (varicella zoster virus)
- Pfeiffer’s glandular fever (Eppstein Barr virus, cytomegalovirus )
- certain types of cancer (herpes virus 8)
Herpes viruses: long-lived, latent, infectious, reactivating
Herpes viruses remain in the body for life after the initial infection, which often goes unnoticed or is asymptomatic. After the initial infection, they withdraw into a stale state. During this phase, they do not form new viruses and therefore go virtually unnoticed by the immune system.
If the virus is reactivated – for example due to a weakening of the immune system – it begins to multiply in the body and can cause symptoms of illness. Reactivation can go unnoticed by those affected, but the virus still multiplies and is excreted. This is precisely why herpes viruses can easily be transmitted to other people and trigger new infections.
Risk factors for herpes
Herpes affects people of all ages and lifestyles. It is estimated that more than two thirds of the world’s population carry herpes viruses, often without realizing it. Initial infections occur particularly frequently in childhood and adolescence. Risk groups are people with a weakened immune system, pregnant women or people under severe stress.
Even a simple cold can weaken the immune system. Negative emotions, heavy physical strain, stress or genetic defects also put the immune system under pressure. People with immunodeficiency diseases such as HIV/AIDS or transplant patients whose immune system is suppressed with medication to prevent organ rejection are particularly at risk.
Possible triggers for herpes on the lip & co.
Herpes infections are usually triggered by factors that weaken or stress the immune system. The most common triggers are
- Weakening of the immune system: illnesses, medication (e.g. immunosuppressants) or a general weakening of the immune system can reactivate herpes viruses.
- Stress: Mental or physical stress can put a strain on the immune system and trigger a herpes infection.
- Fever: High temperatures, for example during a cold or flu, can reactivate the virus.
- Hormonal changes: Hormonal fluctuations (e.g. during menstruation or pregnancy) can trigger herpes, especially in women.
- UV radiation: Intense sun exposure or sunburn can activate the virus, especially in the case of cold sores.
- Injuries or local irritation: For example, due to surgery, dental treatment or skin injuries.
Transmission of herpes viruses
Herpes viruses are transmitted in different ways depending on the type, often through direct contact or via bodily fluids. Here is an overview of the most common transmission routes:
Direct contact
- Skin-to-skin contact: Herpes viruses such as HSV-1 (cold sores) or HSV-2 (genital herpes) are often passed on through direct skin or mucous membrane contact, especially in the case of active blisters.
- Kissing: HSV-1 in particular can be easily transmitted through saliva and contact with infected cold sores.
Transmission through body fluids
- Saliva: Viruses such as HSV-1, EBV (Epstein-Barr virus) and CMV (cytomegalovirus) can be transmitted through saliva.
- Sexual contact: HSV-2 (genital herpes) and KSHV often spread from carriers to uninfected persons through sexual intercourse.
Droplet infection
- Aerosol infection: Some herpes viruses, such as the varicella zoster virus (VZV), can be transmitted via the air, e.g. through tiny droplets when coughing or sneezing.
Transfer during birth
- From mother to child: Herpes viruses such as HSV-2 or CMV can be passed on from an infected mother to the newborn during birth.
Transmission through shared objects
- Shared objects: Non-infected people can become infected with herpes viruses such as HSV-1 through shared glasses, cutlery, towels or lip care products if the viruses survive on them.
Infections with herpes simplex viruses: cold sores and genital herpes
The herpes simplex virus (HSV) is one of the best-known herpes viruses and is divided into two types: HSV-1 and HSV-2. According to estimates by the World Health Organization (WHO), around two thirds of the world’s population are infected with HSV-1.
- HSV-1 is mainly transmitted through saliva and mainly causes blisters in the lip area, also known as cold sores (herpes labialis).
- HSV-2, on the other hand, spreads through sexual contact and is the most common cause of genital herpes in women and men. Doctors usually treat genital herpes with ointments and tablets. Important: You should always consult a doctor if you have genital herpes.
- However, both types of virus can cause cold sores and genital herpes as well as ocular herpes or nasal herpes.
In rare cases, HSV-1 leads to serious complications such as life-threatening encephalitis. As there is no effective vaccination against either herpes simplex virus, treatment is limited to alleviating the symptoms.
Infections with the varicella zoster virus (HHV-4): Chickenpox and shingles
The varicella zoster virus (human herpes virus type 3) is responsible for two diseases: chickenpox (varicella) and shingles (herpes zoster).
Chickenpox – an often underestimated childhood disease
In an initial infection, which often occurs in childhood, the varicella zoster virus triggers chickenpox. Chickenpox typically begins with an itchy skin rash, fever and blisters. The disease usually heals without scarring. Scratching or bacterial infection can lead to permanent skin damage.
Newborns, pregnant women and people with weakened immune systems are particularly at risk. In these cases, serious, sometimes life-threatening complications such as pneumonia (varicella pneumonia), bacterial infections or, more rarely, neurological diseases can occur.
Over 95 percent of adults in Switzerland have had chickenpox in childhood. Only those who have had chickenpox can contract shingles (herpes zoster).
Shingles – the risk increases with age
After surviving chickenpox, the virus remains inactive in the nerve cells of the body. Later in life, reactivation can lead to shingles. One in three adults is affected at some point, usually from the age of 50. Shingles often begins with burning nerve pain, followed by a rash of blisters that often appear on the trunk, chest or head. Even after the rash has healed, the pain can persist for months to years (post-herpetic neuralgia). A vaccination can protect you from an outbreak of shingles with its unpleasant side effects. Although it does not offer 100% protection, it reduces the severity of the disease and significantly lowers the risk of chronic nerve pain.
Infection with the Epstein-Barr virus (HHV-4) - potentially carcinogenic
The Epstein-Barr virus (EBV, HHV-4) is one of the most widespread viruses in the world. Around 95 to 98% of all people have been infected with the Epstein-Barr virus by the age of 50. The virus is the causative agent of Pfeiffer’s glandular fever (also known as infectious mononucleosis). If the infection with EBV occurs in childhood, the disease is usually mild or even asymptomatic. However, if the initial infection occurs in adolescence or adulthood, the symptoms are often more pronounced: Fatigue, fever, headache and aching limbs, sore throat, swollen lymph nodes and an enlarged spleen.
EBV is mainly transmitted through saliva, but also through blood, sexual contact, blood transfusions or transplants. In people with a weakened immune system, it can lead to more serious complications such as inflammation of the lungs, nervous system or heart. EBV is also associated with various types of cancer, including nasopharyngeal cancer (nasopharyngeal carcinoma) and malignant lymphomas such as Burkitt’s lymphoma and Hodgkin’s lymphoma.
Infection with the cytomegalovirus (HHV-5)
The cytomegalovirus (human herpesvirus type 5, also known as human cytomegalovirus, HCMV for short) is one of the most common herpes viruses. It spreads through sexual and non-sexual contact with bodily secretions. In Switzerland, around 40% of adults are infected with the virus. An initial infection is usually asymptomatic. In people with a weakened immune system (e.g. transplant patients), the cytomegalovirus can lead to serious complications such as organ damage to the lungs, liver or eyes. Unborn children who become infected with the cytomegalovirus in the womb are also particularly at risk. An infection can lead to severe damage such as hearing loss or microcephaly, a malformation of the skull. In adolescents and young adults, a ZMV infection can trigger a form of infectious mononucleosis (Pfeiffer’s glandular fever).
Infection with HHV-6 and HHV-7 - the unknown viruses
Human herpesviruses 6 (HHV-6) and 7 (HHV-7) are closely related to the cytomegalovirus. More than 85% of adults are infected with these viruses. HHV-6 is available in two types: A and B.
No specific clinical pictures have yet been observed for HHV-6A. HHV-6B is the main cause of the common three-day fever (Roseola infantum), a childhood illness with fever and a sudden rash on the face and body. The rash usually spreads to the legs after the fever has subsided. Accompanying symptoms can include diarrhea, coughing and swollen lymph nodes. The disease usually affects children aged between six and 24 months and is often mild, sometimes even asymptomatic.
HHV-7 can also cause three-day fever with accompanying seizures in small children. In this case, the fever may be higher and neurological symptoms are possible. As with other herpes viruses, infections with HHV-6 and HHV-7 can be more severe in people with a weakened immune system.
Infection with the Kaposi's sarcoma-associated herpes virus (HHV-8)
Kaposi’s sarcoma-associated herpesvirus (KSHV, HHV-8) is particularly common in certain regions of Africa, where almost half of the population can be infected. In Europe and North America, the incidence is significantly lower at less than 10%.
KSHV rarely causes tumors in people with a healthy immune system. However, KSHV can cause serious illness in immunocompromised people, e.g. HIV-positive patients. It is the main cause of Kaposi’s sarcoma, the most common tumor in AIDS patients, and can also trigger primary effusion lymphoma (a B-cell lymphoma) and multicentric Castleman’s disease (Castleman’s disease).
Herpes treatment
A herpes virus infection can usually be treated with antiviral medication. They are designed to inhibit virus replication and alleviate symptoms. Frequently used active ingredients are acyclovir, valaciclovir and famciclovir.
Herpes treatment options at a glance:
- Local: creams, ointments or eye drops for the treatment of skin and eye infections
- Systemic: Tablets or infusions for severe cases or immunodeficiency
- Symptomatic: pain and anti-inflammatory medication for symptoms
Early treatment can prevent complications, but cannot completely cure the infection, as herpes viruses remain in the body for life.
Details of the treatments
