Herpes Simplex in Newborns (Neonatal Herpes)
The short answer
Neonatal herpes is a rare but serious infection caused by the herpes simplex virus (HSV), most often transmitted during delivery. It can also be transmitted after birth through contact with cold sores or herpes lesions. Early recognition and treatment with antiviral medication (acyclovir) are critical. Prevention includes cesarean delivery if active genital lesions are present and avoiding contact between cold sores and the baby.
Parents everywhere have the same worry. You are doing the right thing by looking into it.
By Age
What to expect by age
Neonatal herpes most commonly presents in the first 2-4 weeks of life. It can appear as skin vesicles (small blisters), eye infection, mouth sores, or in severe cases, can affect the brain (encephalitis) or multiple organs (disseminated disease). Risk is highest when the mother has a primary (new) genital herpes infection near delivery. Any newborn with blisters, vesicles, or signs of illness should be urgently evaluated. Treatment with intravenous acyclovir is started immediately when herpes is suspected. After birth, anyone with an active cold sore should not kiss the baby and should practice strict hand hygiene.
Herpes infection can still occur through contact with active lesions. If your baby was treated for neonatal herpes, they will typically receive oral suppressive acyclovir therapy for 6 months to prevent recurrence. Continue to protect your baby from exposure to cold sores.
If treated early, many babies with neonatal herpes recover well. Babies who had skin, eye, or mouth disease have the best outcomes. Those who had brain or disseminated disease may need developmental follow-up. Continue antiviral prophylaxis as prescribed.
Ongoing monitoring continues for babies who had neonatal herpes. Developmental assessments may be recommended for those who had CNS involvement. The risk of herpes transmission from cold sores and skin contact continues to require vigilance.
What Should You Do?
When to take action
- Baby has no blisters, vesicles, or concerning symptoms despite known herpes exposure, and monitoring period has passed
- Your baby was exposed to someone with an active cold sore or herpes lesion
- You have a history of genital herpes and want to discuss risk and prevention
- You notice any unusual skin lesions on your newborn
- Any blisters, vesicles, or clusters of sores on your newborn's skin, mouth, or eyes require immediate emergency evaluation
- Baby becomes lethargic, refuses to feed, develops a fever, or has seizures, which could indicate disseminated or CNS herpes
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Medical Concerns
Signs of Infection and Sepsis in Newborns
Neonatal sepsis is a serious bacterial infection in the bloodstream that can develop in the first month of life. Signs are often subtle and can include temperature instability, poor feeding, lethargy, irritability, rapid breathing, and a "just not right" appearance. Neonatal sepsis is a medical emergency requiring immediate antibiotics. Trust your instincts if your newborn seems unwell.
Eye Infection and Discharge in Newborns (Conjunctivitis)
Eye discharge in newborns is common and can be caused by a blocked tear duct (most frequent), chemical irritation from eye prophylaxis, or infection. While most sticky eyes are harmless, any significant redness, swelling, or pus-like discharge in the first month should be evaluated promptly, as certain infections can damage the eye.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.
How to Advocate for Your Child's Needs
You know your child better than anyone, and your observations matter. If you feel something is not right with your child's development or health, you have every right to ask questions, request evaluations, and seek second opinions. Advocating for your child is not being difficult - it is being a good parent.