The terms sore throat, strep throat, and tonsillitis often are used interchangeably, but they don't mean the same thing.
Strep throat is an infection caused by a specific type of bacteria, Streptococcus. When your child has a strep throat, the tonsils are usually very inflamed, and the inflammation may affect the surrounding part of the throat as well.
Tonsillitis is inflammation (swelling) of the tonsils.
Other causes of sore throats include viruses, which may cause inflammation only of the throat around the tonsils and not of the tonsils themselves.
Strep throat is caused by a bacterium called Streptococcus pyogenes or group A Streptococcus. Strep throat is most common among school-age children and adolescents, peaking at 7 or 8 years of age. To some extent, the symptoms of strep throat depend on the child's age.
Children over three years of age with strep may have an extremely painful throat, fever over 102 degrees Fahrenheit (38.9 degrees Celsius), swollen glands in the neck and pus on the tonsils.
Cough, runny nose, hoarseness (changes in your voices that make sound raspy) and conjunctivitis (also called pinkeye) are not symptoms of strep throat. If your child has these symptoms, a virus may be the cause of illness instead. It's important to be able to distinguish a strep throat from a viral sore throat, because strep infections are treated with antibiotics.
Other infections that can cause a sore throat
In infants, toddlers and preschoolers, the most frequent cause of sore throats is a viral infection. No specific medicine is required when a virus is responsible, and your child should get better over a 7- to 10-day period. Often children who have sore throats due to viruses also have a cold at the same time. They may develop a mild fever, too, but they generally aren't very sick.
One particular virus (called Coxsackievirus), seen most often during the summer and fall, may cause your child to have a somewhat higher fever and more difficulty swallowing. This virus can also cause a sicker overall feeling. If your child has a Coxsackie infection, they may have one or more blisters in their throat and on their hands and feet (often called Hand, Foot, and Mouth disease).
Infectious mononucleosis (often called "Mono") can produce a sore throat, often along with tonsillitis. However, most young children who are infected with the mononucleosis virus have few or no symptoms.
Diagnosing & treating a sore throat
Call your pediatrician if your child has a sore throat that persists (not one that goes away after their first drink in the morning)—whether or not it is accompanied by fever, headache, stomachache or extreme fatigue. That call should be made even more urgently if your child seems extremely ill, or if they have difficulty breathing or extreme trouble swallowing (causing them to drool). This may indicate they have a more serious infection, such as epiglottitis.
Rapid strep test
Most pediatric offices perform rapid strep tests that provide findings within minutes. If the rapid strep test is negative, your doctor may confirm the result with a throat culture (see below). A negative test means that the infection is presumed to be due to a virus. In that case, antibiotics (which work against bacteria, not viruses) will not help and need not be prescribed.
The doctor will perform a throat culture to determine the nature of the infection. This involves touching the back of the throat and tonsils with a cotton-tipped applicator. The tip is then sent to a lab, where it is smeared onto a special culture dish that allows strep bacteria to grow if they are present. The culture dish usually is examined 24 hours later for the presence of the bacteria.
If the test shows that your child does have strep throat, your pediatrician will prescribe an antibiotic to be taken by mouth or by injection (a shot).
If your child is given the oral antibiotics, it's very important that they take it for the full course, as prescribed—even if the symptoms get better or go away.
If a child's strep throat is not treated with antibiotics, or if they don't complete the treatment, the infection may worsen or spread to other parts of their body. This can lead to conditions such as abscesses of the tonsils or kidney problems. Untreated strep infections also can lead to rheumatic fever, a disease that affects the heart. However, rheumatic fever is rare in the United States and in children under 5 years old.
Is strep throat and other types of throat infection contagious?
Most types of throat infections are contagious. They are passed primarily through the air on droplets of moisture or on the hands of someone infected. For that reason, it makes sense to keep your child away from people who have symptoms of strep throat and other throat infections. However, most people are contagious before their first symptoms appear. So, there's often no practical way to prevent your child from contracting the disease.
If my child gets strep throat a lot, should they have their tonsils out?
In the past when a child had several sore throats, their tonsils might have been removed in an attempt to prevent further infections. But this operation, called a tonsillectomy, is recommended today only for the most severely affected children. Even in difficult cases, where there is repeated strep throat, antibiotic treatment is usually the best solution.