Neonatal Sepsis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Neonatal Sepsis?
A neonatologist, a doctor who cares for sick newborns, usually treats neonatal sepsis in the hospital. A pediatrician, a doctor for babies and children, may be the first to see the signs. A baby with signs of sepsis needs help right away. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is neonatal sepsis?
Neonatal sepsis is a blood infection in babies younger than 90 days old. Early-onset sepsis is seen in the first week of life. Late-onset sepsis happens after 1 week and up to 3 months of age.
Symptoms
Babies with neonatal sepsis may have:
- Changes in body temperature.
- Breathing problems.
- Diarrhea or fewer bowel movements.
- Low blood sugar.
- Reduced movements.
- Reduced sucking.
- A slow or fast heart rate.
- A swollen belly.
- Vomiting.
- Yellow skin and eyes, called jaundice.
- Seizures.
The CDC lists signs of group B strep disease in newborns. They include fever, trouble feeding, being limp or hard to wake up, trouble breathing, and blue-ish skin. These signs can seem like other newborn health problems.
Causes and who gets it
Bacteria can cause neonatal sepsis. Examples are Escherichia coli (E. coli), Listeria, and some strains of streptococcus. Group B streptococcus (GBS) has been a major cause. It is now less common, because women are screened for GBS in pregnancy. The herpes simplex virus can also cause severe infection in a newborn. This happens most often when the mother is newly infected.
Early-onset sepsis most often appears within 24 to 48 hours of birth. The baby gets the infection from the mother before or during delivery. Risks for early-onset sepsis include:
- GBS germs in the mother during pregnancy.
- Birth that is too early.
- Water breaking more than 18 hours before birth.
- Infection of the placenta tissues and amniotic fluid, called chorioamnionitis.
- Amniotic fluid stained with the baby's first stool.
Late-onset sepsis starts after delivery. Risks include having a catheter in a blood vessel for a long time and a long hospital stay.
How doctors diagnose it
Blood tests can help find sepsis and its cause. They may include a blood culture, a C-reactive protein test, and a complete blood count (CBC). If a baby has symptoms, a spinal tap is done. This checks the spinal fluid for bacteria. Skin, stool, and urine tests may check for herpes virus. A chest x-ray is done if the baby has a cough or problems breathing.
Treatment
Babies younger than 4 weeks old who have fever or other signs of infection are started on antibiotics through a vein right away. It may take 24 to 72 hours to get lab results. Some high-risk newborns also get antibiotics at first, even with no symptoms. One example is a baby whose mother had chorioamnionitis.
The baby gets antibiotics for up to 3 weeks if bacteria are found in the blood or spinal fluid. Treatment is shorter if no bacteria are found. An antiviral medicine called acyclovir is used for infections that may be caused by herpes virus. A baby who already went home is most often admitted to the hospital.
Many babies with bacterial infections recover completely. But neonatal sepsis is a leading cause of infant death. The faster a baby gets treatment, the better the outcome. Complications can include disability or death. GBS can also cause deafness and developmental disabilities.
Some pregnant women get preventive antibiotics. This includes women with chorioamnionitis or group B strep, or who had a baby with bacterial sepsis before.
When to see a doctor
Get medical help right away for any baby who shows signs of neonatal sepsis. Call 911 or go to the emergency room if a baby has trouble breathing, a blue-ish skin color, a seizure, or is limp or hard to wake up.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Such a doctor can help with follow-up after a hospital stay. The doctor can also coordinate care with specialists.
Common questions
Is neonatal sepsis serious?
Yes. Neonatal sepsis is a leading cause of infant death. Many babies with bacterial infections recover completely, and faster treatment leads to better results.
What is the difference between early-onset and late-onset sepsis?
Early-onset sepsis is seen in the first week of life, while late-onset sepsis happens after 1 week through 3 months of age. Early-onset sepsis comes from the mother before or during delivery. Late-onset sepsis starts after delivery.
Can neonatal sepsis be prevented?
Some cases can be. Early-onset group B strep disease can be prevented with antibiotics given to the mother during labor. The CDC says no effective strategy has yet been found to prevent late-onset group B strep disease.
What are the first signs of sepsis in a newborn?
Signs can seem like other problems in newborns. They include feeding trouble, fever, being limp or hard to wake up, trouble breathing, and a blue-ish skin color. Get medical help right away if you see them.
Sources
- MedlinePlus - Neonatal sepsis
- Centers for Disease Control and Prevention - Symptoms of Group B Strep Disease
- Centers for Disease Control and Prevention - Clinical Overview of Group B Strep Disease
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
