Herpes simplex - Complications


An in-depth report on the causes, diagnosis, treatment, and prevention of herpes simplex.

Alternative Names

Genital herpes; Fever blisters; Cold sores; HSV-1; HSV-2


The severity of symptoms depends on where and how the virus enters the body. Except in very rare instances and in special circumstances, the disease is not life threatening, although it can be very debilitating and cause great emotional distress.

Herpes and Pregnancy

Pregnant women who are infected with either herpes simplex virus 2 (HSV-2) or herpes simplex virus 1 (HSV-1) genital herpes have a higher risk for miscarriage, premature labor, retarded fetal growth, or transmission of the herpes infection to the infant while in the uterus or at the time of delivery.. Herpes in newborn babies (neonatals) can be a very serious condition.

Fortunately, neonatal herpes is rare. Although about 25 - 30% of pregnant women have genital herpes, less than 0.1% of babies are born with neonatal herpes. The baby is at greatest risk from an asymptomatic infection during a vaginal delivery in women who acquired the virus for the first time late in the pregnancy. In such cases, 30 - 50% of newborns become infected. Recurring herpes and a first infection that is acquired early in the pregnancy pose a much lower risk to the infant.

The reasons for the higher risk with a late primary infection are:

  • During a first infection, the virus is shed for longer periods, and more viral particles are excreted.
  • An infection that first occurs in the late term does not allow the mother to develop antibodies that would help her baby fight off the infection at the time of delivery.

The risk for transmission also increases if infants with infected mothers are born prematurely, if there is invasive monitoring, or if instruments are required during vaginal delivery. Transmission can occur if the amniotic membrane of an infected woman ruptures prematurely, or as the infant passes through an infected birth canal. This increased risk is present if the woman is having or has recently had an active herpes outbreak in the genital area.

Very rarely, the virus is transmitted across the placenta, a form of the infection known as congenital herpes. Also rarely, newborns may contract herpes during the first weeks of life from being kissed by someone with a herpes cold sore.

Infants may acquire congenital herpes from a mother with an active herpes infection at the time of birth. Aggressive treatment with antiviral medication is required, but may not help systemic herpes.
Congenital herpes

Unfortunately, only 5% of infected pregnant women have a history of symptoms, so in many cases herpes infection is not suspected, or symptoms are missed, at the time of delivery. If there is evidence of an active outbreak, doctors usually advise a Cesarean section to prevent the baby contacting the virus in the birth canal during delivery.

Approach to the Pregnant Herpes Patient. The approach to a pregnant woman who has been infected by either HSV-1 or HSV-2 in the genital area is usually determined by when the infection was acquired and the mother's condition around the time of delivery:

  • Obtaining routine herpes cultures on all women during the prenatal period is not recommended.
  • Performing chorionic vilus sampling, amniocentesis, and percutaneous fetal blood draws can safely be performed during pregnancy.
  • Using fetal scalp techniques if considered necessary is considered reasonable if there has been no recent genital herpes outbreaks
  • If lesions in the genital area are present at the time of birth, Cesarean section is usually recommended. (Even a Cesarean section is no guarantee that the child will be virus-free, and the newborn must still be tested.)
  • If lesions erupt shortly before the baby is due then samples must be taken and sent to the laboratory. Samples are cultured to detect the virus at 3 - 5-day intervals prior to delivery to determine whether viral shedding is occurring. If no lesions are present and cultures indicate no viral shedding, a vaginal delivery can be performed and the newborn is examined and cultured after delivery.
  • Some doctors recommend anti-viral medication for pregnant women who are infected with HSV-2. Recent studies indicate that acyclovir (Zovirax) or valacyclovir (Valtrex) or famciclovir (Famvir)Valtrex can help reduce the recurrence of genital herpes and the need for Cesarean sections. Women begin to take the drug on a daily basis beginning in the 36th week of pregnancy (last trimester).
  • Breast-feeding after delivery is safe unless there is a herpes lesion on the breast.

Potential Effects of Herpes in the Newborn

Herpes infection in a newborn causes vague symptoms, such as skin rash, fevers, mouth sores, and eye infections. If left untreated, neonatal herpes is a very serious and even life-threatening condition. Neonatal herpes can spread to the brain and central nervous system causing encephalitis and meningitis and leading to mental retardation, cerebral palsy, and death. Herpes can also spread to internal organs, such as the liver and lungs.

Infants infected with herpes are treated with acyclovir. It is important to treat babies quickly, before the infection spreads to the brain and other organs.

Effects on the Brain and Central Nervous System

Herpes Encephalitis. Each year in the U.S., herpes accounts for about 2,100 cases of encephalitis, a rare but extremely serious brain disease. Herpes simplex virus 1 (HSV-1) is usually the cause, except in newborns. In about 70% of cases of infant herpes encephalitis, the disease occurs when a latent herpes simplex virus 2 (HSV-2) is activated. Untreated, herpes encephalitis is fatal over 70% of the time. Respiratory arrest can occur within the first 24 - 72 hours. Fortunately, rapid diagnostic tests and treatment with acyclovir have both significantly improved survival rates and reduced complication rates. For those who recover, nearly all suffer some impairment, ranging from very mild neurological changes to paralysis. Recovery from herpes encephalitis depends on the patient's age, the level of consciousness, duration of the disease, and the promptness of treatment. The best chances for a favorable outcome occur in patients who are treated with acyclovir within 2 days of becoming ill.

Herpes Meningitis. Herpes meningitis, an inflammation of the membranes that line the brain and spinal cord, occurs in up to 10% of cases of primary genital HSV-2. Women are at higher risk than men for herpes meningitis. Symptoms include headache, fever, stiff neck, vomiting, and sensitivity to light. Fortunately, herpes meningitis usually resolves without complications, lasting for up to a week, although recurrences have been reported.

Meninges of the brain
Click the icon to see an image of the meninges of the brain.

Eczema Herpeticum

A form of herpes infection called eczema herpeticum, also known as Kaposi's varicellum eruption, can affect patients with skin disorders and immunocompromised patients. The disease tends to develop into widespread skin infection that resembles impetigo. Symptoms appear abruptly and can include fever, chills, and malaise. Clusters of dimpled blisters emerge over 7 - 10 days and spread widely. They can become secondarily infected with staphylococcal or streptococcal organisms. When treated, lesions heal in 2 - 6 weeks. Untreated, this condition can be extremely serious and possibly fatal.

Ocular Herpes and Vision Loss

Herpetic infections of the eye (ocular herpes) occur in about 50,000 Americans each year. In most cases it causes inflammation and sores on the lids or outside of the cornea that go away in a few days.

Click the icon to see an image of the eye.

Stromal Keratitis. Stromal keratitis occurs in up to 25% of cases of ocular herpes. In this condition, deeper layers of the cornea are involved, possibly as an abnormal immune response to the original infection. In these rare cases, scarring and corneal thinning develop, which may cause the eye's globe to rupture, resulting in blindness. Although rare, it is the major cause of corneal blindness in the US.

Iridocyclitis. Iridocyclitis is another serious complication of ocular herpes, in which the iris and the area around it become inflamed.


Herpes can cause multiple painful ulcers on the gums and mucous membranes of the mouth, a condition called gingivostomatitis. This condition usually affects children 1 - 5 years of age. It nearly always subsides within 2 weeks. Rarely, it can lead to a viral infection. Children with gingivostomatitis commonly develop herpetic whitlow (herpes of the fingers).

A herpetic whitlow is an infection of the herpes virus around the fingernail. In children, this is often caused by thumbsucking or finger sucking while they have a cold sore. It is seen in adult health care workers, such as dentists, because of increased exposure to the herpes virus. The use of rubber gloves prevents herpes whitlow in health care workers.
Herpetic whitlow on the thumb

Herpes in Patients with Compromised Immune Systems

Herpes simplex is particularly devastating when it occurs in immunocompromised patients and, unfortunately, coinfection is common. People infected with herpes have a three-fold increased risk for contracting HIV. Furthermore, studies have reported that 68 - 81% of patients with HIV are also infected with herpes simplex virus 2 (HSV-2).

Patients with HIV are particularly vulnerable to complications. When a person has both viruses, there appears to be a synergy between them, with each virus increasing the severity of the other. HSV-2 infection increases HIV levels in the genital tract, which makes it easier for the HIV virus to be transmitted to sexual partners. In addition, episodes of herpes recurrence increase, at least temporarily, HIV viral load. Researchers are investigating whether treatment of HSV-2 may help reduce the risk of HIV transmission.

Herpes simplex in any patient with a seriously compromised immune system can cause serious and even life-threatening complications, including:

  • Pneumonia
  • Inflammation of the esophagus
  • Encephalitis (inflammation of the brain)
  • Destruction of the adrenal glands
  • Disseminated herpes (spread of infection throughout the body)
  • Liver damage, including hepatitis



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