Do Newborns Get Strep Throat? Complete Science Guide

No, newborns do not get typical strep throat. The version of strep throat that school-age children and adults get—caused by Group A Streptococcus (GAS)—is extremely rare in babies under six months old. What parents and doctors actually worry about in newborns is a different, more serious bacterial infection called Group B Streptococcus (GBS), which is not strep throat at all. This guide explains the difference between these two conditions, what symptoms to watch for, and when to call a doctor. The science is clear: the illness you probably think of as “strep throat” almost never happens in newborns, but a different strep-related infection does require immediate attention.

Why Don’t Newborns Get Strep Throat Like Older Kids?

The short answer is biology and exposure. Strep throat is caused by Group A Streptococcus bacteria. These bacteria spread through respiratory droplets—coughing, sneezing, sharing cups. Newborns have very limited exposure to other people. They are mostly at home with parents or a small number of caregivers. This limits their chance of catching it.

But there is another reason. A newborn’s immune system is still developing. It does not react to Group A Strep the same way an older child’s does. In older kids, the immune response to GAS causes the classic red, swollen throat and fever. In newborns, the same bacteria might cause a different set of symptoms—or none at all. Some research suggests that babies under three months rarely develop the typical sore throat and tonsillitis from GAS because their immune system has not yet learned to mount that specific inflammatory response.

Current research confirms that Group A Strep pharyngitis—the medical name for strep throat—is virtually nonexistent in the first six months of life. A 2020 review in Pediatric Infectious Disease Journal found that among infants under 90 days old with confirmed GAS infection, only a small fraction had throat symptoms. Most had skin infections or fever without a clear source. So while a newborn can technically carry Group A Strep bacteria, they almost never get the sore throat version of the illness.

What Is Group B Strep and Why Is It Different?

This is where confusion starts. Group B Streptococcus (GBS) is a different bacterium from the one that causes strep throat. It lives naturally in the digestive tract and vagina of about one in four healthy women. It is not a sexually transmitted infection. It is just part of the normal bacterial landscape.

The danger for newborns comes during delivery. If a mother carries GBS in her vagina, the baby can swallow or inhale the bacteria while passing through the birth canal. This can lead to early-onset GBS disease within the first week of life. The infection can cause pneumonia, sepsis, or meningitis. This is serious. Before routine screening began in the 1990s, GBS was a leading cause of newborn death in the United States.

Today, pregnant women are screened for GBS between 36 and 37 weeks. If positive, they receive intravenous antibiotics during labor. This has reduced early-onset GBS disease by about 80 percent. But it has not eliminated it entirely. Some cases still occur, especially if a mother delivers before her GBS status is known or if antibiotics were not given in time.

It is critical to understand that GBS is not strep throat. It does not cause a sore throat in babies. It causes breathing problems, fever, lethargy, and poor feeding. The treatment is intravenous antibiotics in a hospital. There is no home remedy. This is a medical emergency.

Can a Newborn Get Strep Throat from a Parent or Sibling?

It is possible but very unlikely. If a parent or older sibling has active strep throat, the baby can be exposed to Group A Strep bacteria. But exposure does not mean the baby will develop strep throat. Most exposed newborns will either clear the bacteria on their own or develop a mild skin infection or fever without a sore throat.

One study from 2018 tracked infants under three months who were exposed to a household member with confirmed Group A Strep. Only about two percent of those infants developed any illness from the exposure. And none of them developed classic strep throat. The babies who did get sick had fever, fussiness, or a red rash—not a sore throat.

That said, if you have strep throat and are caring for a newborn, standard precautions make sense. Wash your hands before holding the baby. Do not kiss the baby on the face. Avoid coughing or sneezing near them. These steps reduce the chance of passing any respiratory infection to the baby, not just strep.

What Symptoms Should Parents Actually Watch For?

For Group A Strep exposure in a newborn, the symptoms are different from older kids. Do not look for a sore throat. The baby cannot tell you their throat hurts anyway. Instead, watch for these signs:

• Fever – A rectal temperature of 100.4°F or higher in a baby under three months
• Fussiness – Crying that is not soothed by feeding or holding
• Poor feeding – Taking less milk than usual or refusing to eat
• Rash – A red, sandpaper-like rash on the chest or abdomen
• Lethargy – Unusually sleepy or hard to wake

For Group B Strep infection, the signs are more urgent. They usually appear within the first 12 to 48 hours after birth, but can show up later. Watch for:

• Difficulty breathing – Grunting, flaring nostrils, or chest retractions
• Fever or low body temperature – Either can be a sign of infection
• Lethargy – The baby is limp, hard to wake, or not moving normally
• Poor feeding – Not interested in eating or unable to suck
• Irritability – High-pitched crying or constant fussing

If you see any of these signs in a newborn, call your pediatrician immediately or go to the emergency room. Do not wait to see if it gets better. Newborns can deteriorate quickly.

How Is Strep Diagnosed and Treated in Newborns?

If a doctor suspects a Group A Strep infection in a newborn, they will swab the baby’s throat or take a blood sample. The rapid strep test works the same way as in older kids, but it is rarely used in newborns because the infection is so uncommon. Blood cultures are more common. They check for bacteria in the bloodstream.

If Group A Strep is confirmed, the treatment is antibiotics. Penicillin or amoxicillin are the standard choices. The baby will likely be admitted to the hospital for intravenous antibiotics and monitoring. Oral antibiotics at home are not standard for newborns with confirmed GAS infection because the risk of complications is higher.

For Group B Strep disease, the treatment is always intravenous antibiotics in a hospital. Penicillin or ampicillin are the first-line drugs. The baby will be monitored for signs of meningitis, pneumonia, or sepsis. Treatment usually lasts 7 to 14 days depending on the severity. Most babies recover fully if caught early.

It is worth noting that as of 2026, there is no vaccine for Group B Strep. Research is ongoing, but nothing is approved yet. The best prevention remains maternal screening and intrapartum antibiotics.

Common Misconceptions About Newborns and Strep

There are several myths about this topic that keep circulating online. Here is what the evidence actually shows.

Myth: A baby with a stuffy nose or cough has strep throat. False. Strep throat does not cause nasal congestion or cough. Those are viral symptoms. If your newborn has a runny nose, it is almost certainly a cold virus, not strep.

Myth: Breastfeeding prevents strep in newborns. Breast milk provides antibodies and immune support, but it does not prevent Group A or Group B Strep infections. Breastfed babies can still get sick. Do not rely on breastfeeding as protection against bacterial infections.

Myth: If the mother had GBS with a previous baby, she will have it again. Not necessarily. GBS colonization can come and go. That is why screening is done during each pregnancy. A woman who tested positive in one pregnancy may test negative in the next.

Myth: Newborns need antibiotics for GBS exposure even if they look fine. Not always. If a mother received adequate antibiotics during labor and the baby is healthy and full-term, many hospitals will simply observe the baby for 48 hours rather than start antibiotics. This practice is supported by current guidelines from the American Academy of Pediatrics.

When Should You Call the Doctor?

Trust your instincts. If something feels off with your newborn, call. Here are specific situations that warrant a call:

Pediatricians would rather see a healthy baby than miss a sick one. Do not hesitate. A quick phone call can save you worry and possibly your baby’s health.