Key facts about genital herpes
Although the most characteristic symptoms of a herpes infection are painful blisters and ulcers, herpes is not primarily a skin condition. Both HSV-1 and HSV-2 can cause genital herpes, but an HSV-2 infection causes more severe symptoms. More women than men are infected with HSV-2 because sexual transmission of HSV is more efficient from men to women than from women to men. Many patients do not seek care since they either have no symptoms after the initial infection, or do not recognise their symptoms as genital herpes.
Prevalence and incidence
Both HSV-1 and 2 are easily transmissible diseases, with high incidence and prevalence throughout the world. The World Health Organization (WHO) estimates that 3.7 billion individuals under the age of 50 (67%) globally have HSV-1 infection and that 491 million individuals aged 15 to 49 (13%) have HSV-2 worldwide.
Herpes - not just a skin condition
Since herpes is a nerve infection, not just a skin condition, infection may also spread via the nervous system to cause spinal nerves damage (radiculopathy) or inflammation to the brain or tissues surrounding the brain and spinal cord (herpes encephalitis and herpes meningitis). Among patients with genital herpes, one third of women and more than 10% of men of men have been reported to develop meningitis, as a complication. Herpes meningitis can also occur without any other herpes symptoms.
The virus can also infect newborns
Neonatal herpes simplex is a life-threatening condition that requires immediate treatment. If left untreated, the virus can affect brain and spinal cord function, as well as damage to the liver, lungs and kidneys. Approximately 70% of untreated infants with herpes encephalitis will experience severe or fatal complications. In a Canadian study, almost 40% of infections resulted in neurologic damage even in treated infants.
A silent pandemic
Only a small proportion of patients actually seek care since they either have no symptoms or do not recognise their symptoms as genital herpes. These individuals may transmit the virus to partners unaware of the risk. Therefore, it is fair to say, genital herpes is a silent epidemic.
"A vaccine against HSV infection would not only help to promote and protect the health and wellbeing of millions of people, particularly women, worldwide, it could also potentially have an impact on slowing the spread of HIV" Dr. Meg Doherty, WHO
The impact of herpes stigma
In addition to the pain and discomfort, and risk of neurological complications, there is also a stigma attached to genital herpes infection. This may cause emotional and psychosocial consequences for infected individuals, including psychological distress, reluctance to seek care, anxiety about telling current and future sexual partners about the diagnosis, and reluctance to engage in future romantic relationships for fears of transmitting the disease to others.
Lack of education and effective herpes testing are barriers to patient care
Patients with an active outbreak can be accurately diagnosed with a swab test. Symptom-free patient can be diagnosed with a blood test, but there is significant risk of receiving an incorrect result. Routine screening is therefore not recommended. This is one of the reasons why, currently, genital herpes is underdiagnosed.
Genital herpes and HIV
HIV-negative people with an active HSV-2 infection have a two to three times greater risk of acquiring HIV. HIV-positive individuals with an active HSV-2 infection are also three to four times more likely to transmit HIV to a sexual partner. Herpes sores provide an entry site for the HIV-virus to actively infect immune cells and pass into the bloodstream.
Short episodes of symptoms occur frequently among HSV-2 infected patients with recurrent genital herpes in the presence of standard dose valaciclovir, one of the most common treatments, and cannot be prevented with high dose antivirals. More potent therapies, including antiviral drugs and therapeutic vaccines, are needed to provide substantial public health benefits.
Two different types of herpes
Two similar but different virus cause herpes. Oral herpes “cold sores or fever blisters”, which is often acquired during childhood, is caused by herpes simplex virus 1 (HSV-1). Genital herpes is more commonly caused by herpes simplex virus 2 (HSV-2), although HSV-1 may also lead to genital ulcers.
Mode of transmission
Genital herpes virus is most often transmitted between partners during vaginal or anal sex. It is also possible for a person to develop genital herpes after exposure to a cold sore on an infected person’s lip during oral sex; in this case, genital herpes is most likely due to infection with HSV-1. Although the greatest risk of transmission is when there are active sores the virus can also be transmitted in the absence of symptoms. People who already have latent HSV-1 are not at risk of reinfection, but they are still at risk of acquiring HSV-2.
The first outbreak usually occurs within a few weeks after infection with the virus. Symptoms tend to resolve within two to three weeks. The signs of an initial (or primary) episode of genital herpes include multiple blisters in the genital area. For women, the sites most frequently involved include the vagina, vulva, buttocks, anus, and thighs. For men, the penis, scrotum, anus, buttocks and thighs may be affected. The blisters may become painful ulcers, which crust over and heal. Some patients may also develop tender, swollen lymph nodes in the groin, joint pain, fever, and headache, and it may be painful to urinate.
After the initial outbreak, the virus travels to a bundle of nerves at the base of the spine, the sacral ganglia, where it remains inactive for a period of time. This is called the latent stage. There are no symptoms during this stage. HSV may establish latency in ganglia throughout the central nervous far removed from the site of primary infection.
Most people infected with genital herpes have no symptoms (are “asymptomatic”) or have very mild symptoms that go unnoticed or are mistaken for another skin condition.
Diagnosing genital herpes
The diagnosis of genital herpes is based on an individual’s medical history, their signs and symptoms, and the results of tests. It is important to distinguish genital herpes from other sexually transmitted diseases, particularly those that also produce genital ulcers, such as syphilis and chancroid. Tests can usually confirm infection and identify which virus (HSV-1 or HSV-2) is responsible. The choice of testing will depend on the symptoms and whether there are active ulcers.
PCR-tests for genital herpes
Polymerase chain reaction (PCR)-based testing and culture are the preferred tests for a patient with active ulcers.
Culture tests for genital herpes
A culture test can be used to detect if virus is present in blisters or ulcers. However, a culture test only detects the virus in about 50 percent of individuals with genital ulcers. The culture is more likely to detect the virus when ulcers are new and open, as compared to when they are older and healing. The test is also more sensitive in individuals experiencing an initial episode of genital herpes than in individuals experiencing a recurrent episode.
Blood tests for genital herpes
Blood tests to detect antibodies may be used when a person has no visible ulcers at the time of the patient visit but has a history of genital ulcers or may have been infected with HSV in the past. Having a positive test for these antibodies indicates that the person was infected with the virus at some time in the past. The results of antibody testing may be negative early on during the initial episode of infection since antibody formation takes a few weeks. The antibody test remains positive for life.
Treatment and management
There is currently no cure for genital herpes. However, outbreaks can be managed to some extent with antiviral drugs and self-care measures.
Three oral antiviral medications are used to treat genital herpes, acyclovir, famciclovir, and valacyclovir. The initial outbreak of genital herpes is usually treated with seven to ten days of one oral antiviral medication.
Suppressive therapy is antiviral treatment that is taken daily to prevent outbreaks.
In contrast to suppressive therapy, in episodic therapy antiviral drugs are only taken when outbreaks occur. Episodic therapy may be recommended for patients having fewer than six outbreaks each year. Episodic treatment does not reduce the frequency of outbreaks, but it can decrease the duration and severity of the symptoms.
Counseling and support
The diagnosis of genital herpes can cause feelings of shame, fear, and distress. Counseling, either with their family health care provider or a mental health professional, is helpful in dealing with the both the practical and emmotional issues that come with a diagnosis. Education is also important that patients and their partners know how to manage outbreaks and the risk of transmission.