Neonatal herpes

Also called Herpes in a baby or Neonatal herpes simplex

Neonatal herpes is a herpes simplex virus infection in a newborn baby. It is rare but can be very serious. It is usually passed on during birth when the mother has genital herpes, especially a first infection late in pregnancy. It can also be caught after birth if someone with a cold sore kisses the baby.

Last updated Nov 9, 2026

What it is

It is treated with antiviral medicine in hospital.

Telling your midwife about genital herpes, and people with cold sores not kissing newborn babies, helps prevent it.

Common signs

  • Being irritable or very sleepy
  • Not feeding
  • High temperature
  • Blisters or sores on the skin, eyes or mouth
  • Breathing problems

How it is usually diagnosed

  • Swabs and blood tests
  • Lumbar puncture

Records worth keeping

Keeping these together makes each appointment easier, especially when you see a new doctor:

  • Pregnancy notes about herpes
  • Baby test results
  • Hospital discharge letters

Questions to ask your doctor

  • Will I need antiviral medicine late in pregnancy?
  • Does the birth plan need to change?
  • What should visitors with cold sores do?

When to get help right away

Call 112 or go to the nearest emergency department if you have:

  • A newborn who is floppy, very sleepy, not feeding, has a fever or new blisters: call 112

This page is general information. It is not a diagnosis and does not replace a doctor who knows your history. Medfold keeps your records organised; it does not interpret them.

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