Strep throat, caused by the bacterium Group A Streptococcus (GAS), is a common infection that typically affects school-aged children. While less frequent in infants under two years old, babies can contract the infection, often from older siblings or family members. The infection must be diagnosed and treated promptly with antibiotics to prevent serious, long-term health issues. Because infants cannot communicate their symptoms, parents need to be aware that the signs of infection in this age group are often dramatically different from those seen in older children.
Atypical Symptoms of Strep in Infants
Infants and toddlers rarely present with the classic sore throat and painful swallowing that characterizes strep infection in school-aged children. Instead, a baby’s symptoms are often generalized and can be easily mistaken for a common cold or other viral illness.
Parents should look for a sudden onset of fussiness, persistent irritability, and a refusal to feed or nurse, suggesting discomfort when swallowing. A persistent high fever without an obvious source is another common indicator. Unlike older children, babies may also exhibit stomach pain, nausea, vomiting, or a thick, bloody nasal discharge.
In some cases, a fine, sandpaper-like red rash may appear on the torso, arms, or legs, indicating scarlet fever, a condition caused by toxins released by the GAS bacteria. Swollen glands in the neck (cervical lymphadenitis) can also be a noticeable sign. If a baby exhibits any combination of these atypical signs, a medical evaluation is warranted.
Confirmed Diagnosis and Treatment Protocols
Diagnosing Group A Streptococcus requires swabbing the back of the throat for testing. The initial step is often a rapid strep test, which provides results within minutes by detecting bacterial antigens. However, the rapid test can produce false negatives, incorrectly indicating that a baby is not infected.
Due to the potential for false negative results and the risk of complications, a negative rapid test is frequently followed up with a throat culture. This involves sending the swab to a laboratory to see if the bacteria grow, a process that takes 24 to 48 hours. For babies, the culture is often considered the definitive diagnostic step to ensure a true infection is not missed.
If the diagnosis is confirmed, the standard treatment is a 10-day course of oral antibiotics, such as amoxicillin or penicillin, which are highly effective against GAS. The full 10-day course must be completed, even if the infant feels better quickly. Stopping antibiotics prematurely risks the infection returning and fails to prevent serious systemic complications. Pain relievers like age-appropriate doses of acetaminophen or ibuprofen can be administered for immediate comfort to manage fever and throat pain.
Understanding Severe Complications
The danger of a strep infection lies not in the acute illness, but in the potential for severe, long-term complications if left untreated. These systemic issues are known as non-suppurative sequelae, caused by the body’s immune response to the infection rather than the spread of the bacteria itself. Prompt antibiotic treatment is the most effective way to prevent these serious outcomes.
One concerning complication is Acute Rheumatic Fever (ARF), an inflammatory condition that can develop two to three weeks after an untreated infection. ARF primarily targets the heart, joints, brain, and skin, potentially leading to permanent damage to the heart valves (rheumatic heart disease). Initiating antibiotic therapy within nine days of symptom onset is generally effective in preventing ARF.
Another serious systemic consequence is Post-Streptococcal Glomerulonephritis (PSGN), which involves inflammation and damage to the kidneys. PSGN can cause symptoms like blood in the urine, high blood pressure, and swelling, typically appearing one to two weeks after the infection. While most children recover fully, a small number may experience long-term kidney impairment.
Localized complications such as peritonsillar abscesses (a pocket of pus near the tonsil) or otitis media (an ear infection) can also occur. However, the primary focus of treatment remains the prevention of the more debilitating systemic conditions, ARF and PSGN.
Reducing Transmission and Identifying Urgent Warning Signs
Group A Streptococcus is highly contagious and spreads through respiratory droplets from coughing or sneezing, or through contact with contaminated surfaces. To protect an infant, frequent and thorough handwashing is the most effective preventative measure, especially before preparing food or touching the baby. Caregivers should also avoid sharing drinking cups or utensils with the baby, particularly if a family member is ill.
If a family member is diagnosed with strep throat, they should be isolated from the infant until they have been on antibiotics for at least 24 hours and their fever has resolved. Regularly cleaning high-touch surfaces and items like toys can also reduce the bacterial load.
While most strep infections are treated easily, parents must recognize specific urgent warning signs that require an immediate emergency medical visit:
- Severe difficulty breathing.
- A refusal to drink that leads to signs of dehydration.
- Extreme lethargy and unresponsiveness.
- The appearance of purple or blood-colored spots or dots on the skin, which may indicate a severe invasive infection or toxic shock.