Last updated date: 10-Apr-2023

Medically Reviewed By

Medically reviewed by

Dr. Lavrinenko Oleg

Medically reviewed by

Dr. Hakkou Karima

Originally Written in English

Strep Throat


    What is a Strep Throat Infection?

    Strep throat is a bacterial infection characterized by pain and inflammation in the throat. Group A Streptococcus (GAS) bacteria cause this widespread infection. Children and adults of all ages can get strep throat. However, it is more common among children aged between 5 to 15 years old. The infection can spread from one person to another through coughing and sneezing. 

    Strep throat can lead to various complications, including rheumatic fever and kidney inflammation if left untreated. Rheumatic fever may cause sore and inflamed joints, a particular form of a rash, and damage to the heart valves. Therefore, if you or your child experience signs and symptoms that might indicate strep throat, you should consult the physician for prompt diagnosis and treatment. 



    A Group Streptococcus is the most prevalent bacterial cause of pharyngitis in children and adolescents, with a winter and early spring peak. GAS pharyngitis is also more likely among school-aged children or those who have a close relationship with school-aged youngsters.

    Typically, the incidence rises between childhood and adolescence, accounting for half of all visits each year. Although there are many visits for pharyngitis each year, the majority of these cases are viral and self-limiting. However, Group A Streptococcus (GAS) is the most prevalent bacterial etiology of acute pharyngitis, accounting for 5–15% of all adult cases and 20%–30% of all pediatric cases.


    Incubation Period of Strep Throat 

    The strep throat incubation duration is usually between two and five days. This denotes that it takes three days on average from the period you get exposed to the bacteria to the development of the symptoms. 

    With or without medication, strep throat goes away on its own and typically lasts for three to seven days. If you're given antibiotics, the symptoms should improve in one or two days. Therefore, you won't be considered contagious after about 24 hours following the first treatment dose.

    If you don't receive any treatment, you may be infectious from the moment you get exposed to the bacteria till the symptoms go away. According to some studies, infectivity can last up to a week afterward.


    Strep throat causes

    The underlying cause of strep throat is the bacterium infection called streptococcus pyogenes, which can also be referred to as group A streptococcus or GAS. One can get the infection through nose, mouth, or eyes exposure to the bacteria. 


    Risk Factors of Strep Throat

    The main risk factors that can increase the chances of contracting strep throat include;

    • Age: The most common victims of strep throat are young children aged between 5 to 15 years. However, younger babies can also acquire the infection, although it's less common and is associated with atypical signs. 
    • Season of the year: Despite the fact that strep throat can strike at any time, it is most common during the winter or early spring. Also, strep throat bacteria thrive in situations where large numbers of people are in close proximity. 
    • Exposure to pollution and smoke: If you smoke or get exposed to second-hand smoke, the particulate matter is likely to irritate the throat or airways. This makes the throat vulnerable to infection from both strep and viruses. Air pollution has the ability to do the same thing. 
    • Hygiene: When it comes to the spread of strep throat infection, hygiene is a major factor. Children can cough into their hands or rub their noses if they don’t use a tissue. According to studies, S. pyogenes can survive for up to three hours on the hands. You should also stop sharing drinks, food, or utensils. Also, kissing is not recommended during infection for obvious reasons. 
    • Close contact: Because of the close quarters, infection is more likely to spread from one person to another. This is common in schools and daycare centers. Also, individuals who live around someone with strep throat are more likely to contract it. 


    Strep throat symptoms

    The signs and symptoms of strep throat tend to vary from person to person, but they usually involve a sore throat. However, not everybody who has strep throat gets a sore throat, particularly at the beginning of the infection. Some of the common strep throat symptoms are; 

    • Pain in the abdomen, particularly in children
    • Unpleasant breath and a bad mouth taste
    • Swallowing problems
    • Symptoms of the flu, including fever, fatigue, headache, pain, cough, and aches
    • Nausea and loss of appetite 
    • Throat irritation
    • Swollen lymph nodes or glands around the neck
    • Tonsils and throat that are swollen and look like cherry red
    • Presence of pockets of pus or white patches on the tonsils 
    • Development of strep throat rash


    Physical examination may reveal the following:

    • Fever
    • Tonsillopharyngeal erythema
    • Exudates (patchy and discrete)
    • Beefy red swollen uvula
    • Lymphadenopathy (tender cervical nodes)
    • Petechiae on the palate
    • Scarlatiniform rash (This generally appears within the first two days of symptoms and is characterized by a finely papular, blanching, and erythematous rash. The neck is frequently the first to be afflicted, and the disease subsequently progresses throughout the trunk and limbs. Resolution happens in nearly the same sequence of appearance and frequently leads to desquamation of the affected regions, usually within 3-4 days.)

    Most of these signs and symptoms may be present in you or your child and may usually indicate strep throat. Virus infection and other diseases may also be the source of these signs and symptoms. For this reason, it’s essential to have the doctor run some tests in order to determine the condition. It's also likely that you'll come into contact with someone who has strep but doesn't have any signs.


    Is strep throat contagious?

    Strep throat is contagious. Apart from sneezing and coughing, the infection can be spread by sharing food and drinks with a sick person. You may also acquire strep throat by rubbing your nose, eyes, or mouth after coming into contact with an object infected with group A strep bacteria, for instance, a faucet or a doorknob. 


    Strep Throat Diagnosis 

    If you are experiencing strep throat-related symptoms or suspect you have the disorder, the doctor will start by conducting a physical test. A physical examination involves assessing the throat and looking for inflammation signs. It can also involve checking the neck for the swollen lymph nodes and inquiring about other associated symptoms you may be experiencing. 

    Because of the wide overlap of signs and symptoms seen in bacterial and viral pharyngitis, as well as the inaccuracy of medical providers in distinguishing GAS pharyngitis from other causes, it is recommended that confirmatory bacterial testing be performed in all cases except when a clear viral etiology is expected.

    Diagnostic testing is not suggested in children under the age of three since GAS pharyngitis and acute rheumatic fever are uncommon in this age range. Children under the age of three who have risk factors, such as siblings with GAS pharyngitis, may be tested.

    If the doctor identifies the symptoms that might indicate infection, he will order more additional strep throat diagnosis tests such as; 

    • Rapid antigen test 

    This test aims at determining if the sore throat is a result of strep infection or a different type of germ and bacteria. It involves strep throat swabs using long swabbing cotton to obtain a sample. It is then brought to the lab for further analysis of bacterial signs. 

    Rapid antigen test is a relatively short procedure that takes about five minutes. If the result is negative and the doctor still suspects strep throat, additional tests might be performed. 

    • Throat culture

    This involves rubbing a sterile swab at the back of the tonsils and throat to obtain a small secretion sample. This procedure is painless but can make one gag. The obtained sample is then brought to the lab to check if bacteria are present. However, the results might take up to two days. 

    • Molecular test (PRC or polymerase chain reaction)

    This procedure involves swabbing the throat to obtain a sample for this examination. Although it’s not fast as the antigen test, they give a definitive outcome and any supplemental testing is not needed. 


    Strep Throat Treatment 

    The key objectives of GAS pharyngitis treatment are to reduce a patient's length and intensity of symptoms, to avoid immediate and delayed consequences, and to prevent infection from spreading to others.

    The available strep throat treatment options aim at curing the throat and alleviating the symptoms. It also prevents it from spreading and causing various complications. They come in the form of strep throat medications such as; 

    • Antibiotics 

    If the results show that you or your child has strep throat, the physician is most likely to recommend an oral antibiotic. This is because strep throat is a bacterial infection. The antibiotic thus helps to relieve the symptoms and limit the infection. However, it is preferable that it be administered within 48 hours of the onset of the disease.

    It's essential that you finish taking the prescribed antibiotics to ensure full elimination of the infection. However, as soon as the symptoms improve, some people refrain from taking medicine, which could lead to a relapse. When this occurs, the symptoms are likely to reappear. It also increases the risks of severe complications, including kidney inflammation and rheumatic fever. 

    With this treatment, the patient will begin to feel better after one or two days. If there is no improvement after 48 hours of taking antibiotics, it is best to contact the attending physician again.

    1. Because of their low cost and minimal side effect profile, penicillin A or amoxicillin is used to treat GAS pharyngitis. 
    2. Amoxicillin is prescribed for children, in the dose to be 50 mg / kg in two doses per day. For adults it is administered at a dose of 2g per day in two doses, the total duration of treatment is between 6 and 10 days of treatment must be completed.

    Within antibiotic therapy, patients may see a reduction in symptoms within one to three days and may return to work or school after 24 hours. A cure test is not advised following a course of therapy unless the patient has a history of severe rheumatic fever or another GAS complication.

    Similarly, post-exposure prophylaxis is not advised unless a patient has a history of severe rheumatic fever, or widespread contamination of the environment. Good hand hygiene is essential for the prevention of diseases transmitted in close quarters.

    • Relievers 

    Doctors can also recommend over-the-counter painkillers like ibuprofen (Advil, Motrin IB, among others) or acetaminophen, including Tylenol, to alleviate throat pain and fever. 

    One should, however, give aspirin to young children and teenagers with caution. On the other hand, children and teenagers healing from chickenpox or flu-like symptoms must not take aspirin. This is irrespective of the fact that aspirin has been approved for use among children over the age of three. Typically, aspirin is associated with Reye’s syndrome, which is a rare yet possible fatal condition in children. 

    • Surgery 

    A surgical operation to remove the tonsils can be recommended for people with chronic and recurring strep throat. However, some complications are associated with surgery, such as bleeding during or after the procedure in some patients. Also, throat pain and feeding problems are common during the first days following surgery. It usually takes about two to three weeks to recover completely. 


    Strep Throat Home Remedies 

    Strep Throat Home Remedies

    Apart from antibiotics, various strep throat home remedies have proven to help ease the symptoms. They include the following; 

    Getting enough rest: Make sure you get plenty of sleep since this aids the body's ability to combat infection. If diagnosed with strep throat, try to stay at home as much as possible. If your child is sick, he or she should remain at home till the fever has gone down, till he or she feels better, and take the antibiotic for at least 24 hours.

    Taking plenty of liquids: This helps maintain a sore throat moist and lubricated at all times. Hence, making swallowing easier and preventing dehydration. 

    Gargling with warm salty water: Doing this numerous times each day can help alleviate throat pain in older children and adults. In 8 ounces (237 milliliters) or a big glace of warm water, add 1/4 teaspoon or 1.5 grams of table salt and mix well. Make sure that your child understands that after gargling, he or she must spit out the liquid and not swallow it.

    Honey: This can help soothe the pain and sore throats. However, honey should not be given to children under the age of 12 months. 

    Consume soothing foods: Soups, broths, applesauce, mashed potatoes, cooked cereal, soft fruits, soft-cooked eggs, and yogurt are examples of easy to swallow foods. Alternatively, to make foods much easier to ingest, puree them with a blender. Frozen yogurt, sherbet, and frozen fruit pops are examples of cold foods that can be calming or soothing. You should, however, avoid spicy foods and those that are acidic, including orange juice. 

    Avoiding irritants and staying away: Cigarette smoke can cause irritation on a sore throat and raise risks of infections like tonsillitis. Paint as well as the cleaning product fumes may irritate the throat and lungs; hence you should avoid them. 

    Using a humidifier: Incorporating moisture into the air can help lessen discomfort. You can choose a cold mist humidifier and clean it on a regular basis, as some humidifiers can harbor molds and bacteria. Nasal saline sprays can also assist in maintaining the mucous membranes moist. 


    Possible Complications of Strep Throat

    Most strep throat patients can recover while at home by using antibiotics as prescribed and taking measures to alleviate symptoms and strengthen the body’s immunity as much as possible to reduce the risk of complications. But occasionally, strep throat can cause severe and life-threatening complications in some children and adults. These strep throat complications can include the following; 

    • Acute glomerulonephritis; is an inflammation of the kidneys that can cause kidney damage as well as kidney failure 
    • Rheumatic fever 
    • Cervical adenitis
    • Sinusitis
    • Infection in the middle ear (otitis media)
    • Peritonsillar abscess 
    • Rheumatic heart disease
    • Scarlet fever


    Acute Rheumatic Fever

    This illness generally manifests itself 2-4 weeks following a bout of pharyngitis. It has been demonstrated that using appropriate antibiotics up to 9 days after the development of pharyngeal symptoms can avoid this appearance. Carditis, polyarthritis, chorea, erythema marginatum, and subcutaneous nodules are the most common symptoms of acute rheumatic fever.

    Fever, polyarthralgia, an increased leukocyte count, an elevated erythrocyte sedimentation rate, and a prolonged P-R interval are minor criteria. The current incidence of this consequence following endemic infection is unclear, however, it is thought to be significantly less than 1%.


    Rheumatic Heart Disease

    This is an acute rheumatic fever with persistent valvular manifestations. The mitral valve is the most commonly affected region, and either regurgitation or stenosis can occur. Long-term secondary prophylaxis, frequently with benzathine penicillin, reduces the incidence of further bouts of acute rheumatic fever and severe heart damage in people with rheumatic heart disease.


    Post Streptococcal Glomerulonephritis

    This normally happens 1-3 weeks after strep throat. Poststreptococcal glomerulonephritis, which can occur after a strep throat skin infection, has not been proved to be prevented with antibiotics. Patients frequently exhibit hematuria, edema, and hypertension.


    Preventing Strep Throat 

    The following strep throat prevention measure can help you reduce the chances of developing the condition; 

    • Washing hands regularly: Hand washing is the most effective way of all types of infections. Due to this, it’s essential to regularly clean your hands using soap and running water for about 20 seconds. You should also show your children how to wash their hands with soap and water appropriately. If possible, teach them ways of using an alcohol-based hand sanitizer when soap and water are not available. 
    • Cover your mouth always: Show your children how to cover their mouths using a tissue or an elbow when sneezing and coughing. 
    • Avoid sharing personal belongings: Drinking cups and eating utensils should not be shared. You should also clean the dishes in hot and soapy water or put them in the dishwasher. 

    If strep infections continue to occur within the family, you can check to determine if anyone is a strep carrier. Carriers have strep bacteria in their lungs, but they are unaffected. It's possible that treating them will prevent anyone from contracting strep throat.  

    The disease is less likely to spread among carriers. Despite the slim risk that they might infect others, it's still debatable if they should be addressed with antibiotics to kill the bacteria. If the carrier has regular close contact with a person who has a poor immune system, this could be a viable choice. It's also worth thinking about whether they have recurring infections. 


    Adults with Strep Throat

    Children are more likely to develop strep throat, unlike adults. The parents of school-aged minors are at a high risk of contracting the bacteria. Also, adults who spend a lot of time with children may be more vulnerable to strep throat. 


    Throat Strep and Sore Throat

    Viruses are the underlying triggers of sore throat, whereas strep throat is caused by group A strep bacteria. A strep infection does not always cause a sore throat. 

    A sore throat may also be as a result of other diseases such as; 

    Sore throats that occur due to other medical problems normally go away on their own after a few days, with or without medication.


    Strep Throat in Toddlers 

    Doctors can sometimes diagnose strep throat in toddlers. While children are more susceptible to strep throat than adults, it is extremely uncommon in toddlers below the age of three. Children aged between 5 and 15 are more likely to develop strep throat. 

    Since it is highly infectious, strep throat spreads quickly in places where the minors congregate. It can be in daycare centers and schools. 


    Strep throat and pregnancy 

    Group A streptococcus, which causes strep throat, is not similar to group B streptococcus, which is present in the rectum or vagina. Although group B streptococcus can be transferred from mother to baby during birth, it is not related to the bacteria causing strep throat. 

    If you suspect you have strep throat while pregnant, consult the doctor as soon as possible to explore treatment options. He or she can give you antibiotics and closely monitor the medications. 


    Strep Throat vs Cold

    The majority of colds occur due to a virus, whereas a bacterial infection causes strep throat. A common cold is characterized by coughing, a running nose, or hoarseness. Such symptoms, particularly coughing, are uncommon in a person with strep throat. 

    If you have a sore throat caused by a cold, the pain normally develops slowly and subsides after a few days. Strep throat pain can strike at any time. It is more serious and can last for several days. 

    fever is a good sign of strep throat, if you have more than 38,5°c, it’s more likely to be a bacterial infection. cold may cause a mild fever without exceeding 38°c.

    In most cases, colds go away on their own and don't need medical attention. Doctors often prescribe antibiotics to cure strep throat and keep off complications such as rheumatic fever.


    Infectious Mononucleosis vs Strep Throat 

    The Epstein-Barr virus is the main cause of infectious mononucleosis, also known as mono or the kissing disease. Teenagers and young adults are the most commonly affected.

    Mono signs are similar to those of strep throat. They include a sore throat, swollen lymph nodes, and fever. However, unlike strep throat, which occurs due to a bacterial infection, mono is caused by a virus. Hence, antibiotics are not used to treat it. The doctor will run some tests to see if the sore throat is because of mono.


    Strep Throat and Tonsillitis 

    You may have seen the words strep throat and tonsillitis used interchangeably; however, this is incorrect. Tonsillitis is a condition that may occur without strep throat. Tonsillitis can be caused by the same bacteria that cause strep throat, group A Streptococcus. But, at times, it can also be caused by other viruses and bacteria. 

    Most of the symptoms of tonsillitis and strep throat are similar. Due to this, strep throat may be considered a form of tonsillitis. People with tonsillitis, on the other hand, will experience additional, distinct symptoms such as; 

    • Swelling and reddening of the tonsils 
    • Stomach upsets 
    • Stiff neck 
    • Yellowish or white discoloration in the tonsils 


    Recovery from Strep Throat

    Strep throat recovery duration is relatively short as the symptoms begin to improve as soon as you start taking medications. If the strep throat symptoms fail to improve 48 hours after using an antibiotic, call your doctor immediately to avoid any complications. To combat the infection, they will have to prescribe a different antibiotic class. Strep throat, if left untreated, can lead to severe complications, which can include the following; 

    • Inflammation of the kidneys (post-streptococcal glomerulonephritis)
    • Guttate psoriasis, a disorder that causes tiny, red teardrop-shaped spots to develop in the body. 
    • Infection in the ear
    • Mastoiditis, a condition in which the mastoid bone within the skull becomes infected.
    • Peritonsillar abscess, a puss-filled infection that occurs behind the tonsils 
    • Rheumatic fever, an inflammatory condition that affects the heart, joints, as well as skin.
    • Scarlet fever, which occurs if toxins produced by the strep infection trigger a scarlet-colored rash to grow on various parts of the body 
    • Sinusitis


    Differential Diagnosis

    • Infectious Causes 
    • Respiratory viruses (parainfluenza, rhinovirus, coxsackievirus, adenovirus, etc.)
    • Arcanobaceterium haemolyticum
    • Mycoplasma species
    • Chlamydia species
    • Corynebacterium diphtheria
    • Acute HIV infection
    • Neisseria gonorrhoeae
    • Treponema pallidum
    • Epstein-Barr virus
    • Fusobacterium necrophorum

    Non-infectious Causes 

    • Allergies
    • Gastroesophageal reflux disease
    • Exposure to second-hand smoke
    • Trauma
    • Autoimmune disorders (Behçet syndrome, Kawasaki, etc.)
    • Foreign body



    Tonsillopharyngeal cellulitis or abscess, otitis media, sinusitis, necrotizing fasciitis, bacteremia, meningitis, brain abscess, and jugular vein septic thrombophlebitis are all suppurative consequences of GAS pharyngitis.

    Acute rheumatic fever, post-streptococcal reactive arthritis, scarlet fever, streptococcal toxic shock syndrome, acute glomerulonephritis, and pediatric autoimmune neuropsychiatric illness linked with group A streptococci are all non-suppurative consequences of GAS pharyngitis.


    When to Consult a Physician 

    Consult a Physician

    Contact the doctor immediately if you or your child exhibits any of the following signs and symptoms; 

    • A sore throat that is followed by swollen and tender lymph glands
    • A sore throat that persists for more than 48 hours
    • Fever and chills
    • A rash that is associated with a sore throat
    • Breathing and swallowing difficulty 
    • Persistence even after taking some antibiotics for 48 hours following strep throat diagnosis 



    Strep throat is a common bacterial infection caused by streptococcus bacteria. Approximately 15% to 30% of cases are diagnosed in children, while 5 to 10 percent of the cases are in adults. It can also spread from one person to another through saliva droplets or nose discharge when one sneezes or coughs. 

    Although streptococcus is the major underlying cause of strep throat, certain factors can make one prone to the disorder. As such, understanding them enables you to reduce the chances of infection. 

    Most cases of pharyngitis resolve without treatment; however, antibiotics are prescribed in approximately 60% of cases to prevent rare complications (e.g., acute rheumatic fever, rheumatic heart disease, post-streptococcal glomerulonephritis), shorten the duration of illness, prevent infection spread to close contacts, and address patient demands.

    An interprofessional team that includes a primary care provider, emergency department physician, otolaryngologist, nurse practitioner, infectious disease consultant, and internist optimizes GAS diagnosis and management. The objective of GAS therapy is to reduce the patient's length and intensity of symptoms, as well as to avoid immediate and delayed consequences and the spread of infection to others.

    Penicillin or amoxicillin are the antibiotics of choice for confirmed strep throat. Clindamycin, clarithromycin, or azithromycin can be used for people who are allergic to penicillin.