Streptococcal pharyngitis

Streptococcal pharyngitis is a common bacterial infection of the pharynx. The pharynx is the part of the throat located at the back of the mouth. This condition is widely known as strep throat. It is caused by a specific bacterium called Streptococcus pyogenes. This germ belongs to a group known as group A streptococcus, or GAS. While many things can cause a sore throat, strep throat is a major cause in children. It is responsible for 15% to 40% of sore throats in children. In adults, it causes between 5% and 15% of sore throats.

The infection spreads primarily through direct contact with an infected person. When an infected person talks, coughs, or sneezes, they release tiny respiratory droplets. These droplets can carry the bacteria into the air or onto surfaces. You can also catch the bacteria by touching something that has these droplets on it. If you then touch your mouth, nose, or eyes, the germ can enter your body. Bacteria can also live on moist items like toothbrushes for up to fifteen days. However, dried bacteria in dust are not considered infectious. Crowded places like schools or the military can increase how fast the germ spreads.

Symptoms of the infection usually appear one to three days after exposure. Most people feel better within seven to ten days. Common signs include a sore throat and a fever higher than 38°C. You might also see tonsillar exudates, which are white spots of pus on the tonsils. Swollen and tender lymph nodes in the front of the neck are also common. Some people experience a headache, nausea, vomiting, or abdominal pain. A specific type of red rash that feels like sandpaper can appear. This condition is known as scarlet fever. If a person has a runny nose, cough, or red eyes, it is more likely they have a viral infection instead.

Doctors use specific tools to determine if a patient has strep throat. One method is the rapid antigen detection test, or RADT. This test provides quick results but is slightly less accurate than other methods. The gold standard for diagnosis is a throat culture. A culture is a laboratory test that has a sensitivity of 90% to 95%. In many places, a negative rapid test is enough to rule out the disease for adults. However, doctors often recommend a throat culture for children to be certain. Some people are "carriers," meaning they have the bacteria in their throat but do not feel sick. About 12% of children without symptoms are carriers.

Medical professionals often use a scoring system to help make a diagnosis. One such system is the modified Centor criteria. This system gives points based on specific signs. You get a point for the absence of a cough. You also get points for swollen lymph nodes, a fever, or tonsillar swelling. The patient's age also affects the score. Doctors use these scores to decide if a patient needs a test or antibiotics. The Infectious Disease Society of America suggests that antibiotics should only be used after a positive test is confirmed.

Antibiotics are the main way to treat a confirmed infection. In the United States, penicillin V is the most common choice because it is safe and effective. In Europe, doctors often prefer amoxicillin. In places like India, where the risk of certain complications is higher, benzathine penicillin G is often used. Antibiotics do not necessarily make the illness go away much faster. They do shorten the duration of symptoms by about 16 hours. The most important reason to use antibiotics is to prevent serious complications. These include rheumatic fever, which can affect the heart, and peritonsillar abscesses.

Preventing the spread of the bacteria is very important for public health. Frequent hand washing is one of the best ways to stay healthy. You should also avoid sharing eating utensils with others. If someone is sick, they should stay away from other people until their fever is gone. They should also wait at least 12 hours after starting antibiotic treatment before returning to normal activities. While there is no vaccine for strep throat, these simple steps can help stop the bacteria from moving from person to person. In the United States alone, the economic cost of this disease in children is about $350 million every year.