MedBlog

Your Pregnancy Matters

How to protect your baby from herpes infection

Your Pregnancy Matters

A mother gently kissing her newborn baby who is wearing a striped hat.
The herpes simplex viruses that cause cold sores or genital sores in adults can cause significant infections in newborns.

About one in six Americans ages 14 to 49 has genital herpes, according to data from the Centers for Disease Control and Prevention. Genital herpes typically is caused by HSV-2, a herpes virus strain. But more than half of adults in America have been infected at some point in their lives with HSV-1, the herpes virus that commonly affects the mouth in the form of cold sores. HSV-1 also can cause genital lesions through oral sex. Both of these viruses can cause significant infections in newborns.

While outbreaks can be painful or unsightly in adults, they pass. But when a newborn is infected with herpes, serious and sometimes fatal complications can occur. In July 2017, an Iowa newborn contracted HSV-1 from someone who visited her shortly after birth. Since both parents tested negative for herpes infections, authorities suggest that someone with a current or recent cold sore likely kissed the baby, infecting her with HSV-1. The infection escalated into viral meningitis, killing the baby.

Herpes infection occurs in less than 1 percent of births, and the development of meningitis from HSV-1 infection is incredibly rare. However, herpes infection in newborns is always a concern, and we want to share information from medical providers about herpes infections in pregnancy as well as recommendations for parents to keep their babies safe.

How do newborns contract herpes?

A study published in January 2017 in The Lancet Global Health states that 85 percent of herpes-infected newborns contract the disease from their mothers during delivery.

It’s fairly common for women to have herpes but not realize it due to mild symptoms or a lack of symptoms. The virus can be inactive for extended periods of time before it causes a lesion. It’s common for HSV to reactivate in times of physical or emotional stress. Herpes can spread when no symptoms are present because the virus sheds intermittently, which means the virus is active but may not cause trademark sores on the body.

For HSV-1, or oral herpes, infection typically happens through contact from an infected person’s lesion to a membrane area of the baby’s body, such as the eyes or mouth. This can happen if a person with a cold sore kisses the baby or, even more rarely, if the individual touches a cold sore and then touches the baby.

What are herpes symptoms and risks for newborns?

Herpes symptoms in infants can be vague, such as difficulty breathing, bleeding easily, or feeding poorly. If sores appear, they can crop up anywhere on the body. In newborns who contract herpes during birth, we typically see sores where the baby’s skin has been broken, such as on top of the head or around the umbilical cord.

HSV-1 and HSV-2 infection puts newborns at high risk for developing severe and life-threatening symptoms, including:

  • Fatal organ damage, including the liver, lungs, and heart
  • Serious viral infections, such as viral meningitis
  • Recurrent sores on the skin, eyes, genitals, or mouth
  • Blindness
  • Deafness
  • Seizures

What can parents do to protect babies from herpes?

If you develop any sores or blisters in the genital area during pregnancy, let your doctor know. It may be something as simple as an infected hair follicle – or it could be something much more serious, such as herpes. By knowing, we can help you and your baby be as healthy as possible during pregnancy and delivery.

Newborns are most at risk when the mother is infected with herpes or has her first outbreak of sores late in pregnancy. There hasn’t been enough time for the mother’s body to develop and share protective antibodies with the baby.
Related reading: What if I have an infectious disease and want to get pregnant?

If your partner has genital herpes and you have never been infected, I recommend abstaining from sex the last few weeks of pregnancy. Condoms can reduce the risk of transmission but aren’t 100 percent effective. It doesn’t make sense to me to take the chance of a new infection that close to delivery.

How do obstetricians and pediatricians protect newborns from herpes?

If a mom presents to Labor and Delivery in labor or for a scheduled induction, we will do a thorough examination of the perineum to look for lesions and a speculum exam to look for lesions on the cervix.

If we see anything suspicious, we will recommend a C-section to help prevent the baby coming in contact with any sores. Contact with active lesions is a major risk factor for infection. If a woman does have a history of herpes before pregnancy but has no sores at the time of delivery, she should be reassured – the risk of transferring it to her baby during birth is less than 1 percent.

To reduce the risk of having an outbreak near delivery, we prescribe antiviral medications such as acyclovir (Valtrex) to pregnant women who have a history of herpes, starting around 36 weeks. This reduces shedding of the virus in the genital area around the time of labor. Reducing shedding also reduces the risk of active lesions at the time of delivery, and that might allow us to avoid C-section.

After delivery, your pediatrician may order extra testing on the newborn. If the baby is thought to be at extremely high risk for HSV infection, we test the blood right away for evidence of viral infection, and we may consider treating the baby with antiviral medications even before the results of those tests are reported. If the test results are positive, the antiviral medications would be continued.

Recommendations for new parents

Whether or not you have herpes yourself, insist that everyone who wants to hold or touch your newborn wash their hands first. This is the No. 1 thing parents can do to safeguard their child from not only HSV-1 and HSV-2 but also other viruses and bacteria that can make your baby sick.

Do not allow anyone with a cold sore, or anyone who you know has had a cold sore in the previous week, to hold or kiss your baby. If you’re concerned about hurting a friend’s or relative’s feelings by declining their visit with your baby, involve your nurse or doctor. We’re happy to have these conversations for you – it’s our job to make sure you and your baby are safe under our care.

When possible, avoid taking your baby to crowded public places for a few months after birth. Herpes infection from incidental touching of strangers or development of other infections from respiratory germs might occur.

Once people are infected with herpes, they’re infected for life, even when symptoms aren’t present. Though a significant number of U.S. adults live with genital herpes and a majority of us have been infected with HSV-1 at some point in our lives, we must never underestimate the devastating effects these viruses can have on infants. As parents and providers, we must do all we can to safeguard our babies from herpes infection.