Strep Throat: Symptoms, Causes, Risks, Complications, Diagnosis, Treatment, Prevention and Prognosis

man with Strep Throat


Strep throat is a bacterial infection in the throat caused by streptococcal (strep) bacteria. As a result, the infection will make your throat feel scratchy, sore and painful.
However, strep throat just accounts for a small portion of sore throats. If this is left untreated, this condition may lead to more serious conditions.

Strep throat is one of the most common throat infections among children, but it can affect other people of all ages.  There are two types of Streptococcus bacteria – Group A and Group B. Group A Streptococci (GAS) is common, and it causes strep throat and other infections such as cellulitis, impetigo, toxic shock syndrome and scarlet fever.

On the other hand, Group B Streptococci causes bacterial infections such as pneumonia, blood infections, and potentially-fatal meningitis, or the inflammation of the membranes surrounding the spinal cord and the brain.

In most cases, a sore throat is usually caused by a virus. However, approximately 15 percent of all sore throats are caused by Streptococcus bacteria. It’s common between the ages of 5 and 15 years old and in babies less than three years old; a strep throat usually develops into otitis media or a middle ear infection.


The severity of strep throat can vary depending on the person infected. In some people, they may only experience mild symptoms while in others, they may have more severe symptoms. However, the most common symptoms of a strep throat include:

  • A sudden fever which is 101 F or higher
  • Painful, sore and red throat, sometimes with white patches
  • Chills
  • Headache
  • Loss of appetite
  • Swollen lymph nodes
  • Painful when swallowing
  • Rash
  • Body aches
  • Nausea and vomiting, especially in small kids

Remember that a strep throat could cause serious complications. It is better to watch out for the following symptoms and if these are present, see a doctor immediately.

  • A sore throat that is accompanied by swollen lymph nodes
  • A sore throat that is present for more than 48 hours
  • A fever higher than 101 F or 38.3 C in kids or a fever that lasts for more than 48 hours
  • Problems with swallowing and breathing
  • A sore throat with a skin rash
  • Body aches
  • Nausea and vomiting, especially in small kids
  • If the antibiotics that were given did not improve the condition for 48 hours


A strep throat is caused by the bacterium called Streptococcus pyogenes, also dubbed as group A streptococcus (GAS). This type of bacteria is highly-contagious and can spread through droplets suspended in the air (airborne transmission).

These droplets get into the air when someone who has the infection coughs or sneezes. There are many ways to get infected – through shared food or drinks, holding a doorknob with the bacteria or any surface and transfer them to your eyes, nose or mouth.

The majority of sore throats are viral, which is self-limiting. This means that the disease goes away on its own even without any treatment. However, a sore throat caused by a bacterium is more serious and may lead to a higher risk of complications.

4Risk Factors

There are many factors that may increase the risk of a strep throat including:


Young children, especially those who are younger than two years old, are at a higher risk of acquiring strep throat.


Though strep throat can occur any time of the year, more cases are reported during the fall, winter and early spring seasons.

Crowded places, buildings, and houses

The bacteria flourish in places where people are in close contact, especially in houses or buildings that are enclosed and have poor ventilation.


People who have the infection may develop potential complications, especially if the condition has been left untreated.

There are various complications that could occur such as middle ear infection (otitis media), which is common among kids, sinusitis or sinus infection, meningitis, pneumonia, kidney disease and rheumatic fever. Of these complications, kidney disease, toxic shock syndrome and rheumatic fever are the most life-threatening.

Kidney Disease

When there is an active infection in the body, the immune system acts to fight the pathogen causing the disease. This response, however, may also cause inflammation of the kidneys. This condition is called post-streptococcal glomerulonephritis. This is a form of kidney disease is less severe than rheumatic fever.

The disease may emerge about one to three weeks after the infection of the throat. The good thing is, this condition can go away on its own. However, children are at a higher risk of developing kidney disease, which may manifest as blood in the urine, puffy eyes and swollen ankles, a typical side effect of edema.

Rheumatic Fever

One of the most serious complications of a strep throat is rheumatic fever. When a strep infection is left untreated or has been inadequately treated, it can lead to the bacteria remaining in the tonsils. As a result, it creates a continuous immune response.
This may lead to the inflammation in various parts of the body including the brain, heart, skin, and joints. This condition is dubbed as rheumatic fever.

Rheumatic fever can happen about two to four weeks after a strep throat infection.
This type of fever has another complication – rheumatic heart disease (RHD). RHD is the inflammation that has affected the scarring of the heart valves, which may require a heart valve replacement surgery. Aside from surgery, other people may opt to receive lifetime medications to prevent recurrent sore throats.

Toxic Shock Syndrome

Toxic shock syndrome caused by a strep throat is rare and potentially life-threatening.
This is usually caused by the toxins released by the GAS bacteria. This may cause a systemic body reaction including low blood pressure, rash, fever and the potential for multi-organ failure.


If you complain of a persistent sore throat, the doctor may examine the throat and assess for any signs of inflammation. Aside from the throat, the doctor may also check for swollen lymph nodes at the back of the neck, the body temperature, and other symptoms.

Other tests that can be used to diagnose a strep throat are complete blood counts, to determine if there is an active infection, rapid antigen tests, and a throat culture.

Complete Blood Count

A complete blood count is a test wherein the doctor will determine if there is an acute infection in the body. If the levels of the white blood cells are elevated, this means that there is an infection.

Rapid Antigen Test

A rapid antigen test involves getting a swab sample from the throat. In here, the test will detect the presence of the strep bacteria. If the result is negative and the doctor wants a confirmatory test, a throat culture is performed.

Throat Culture

In a throat culture, the doctor may use a sterile swab and rub it over the back of the throat and the tonsils. The sample is then cultured in the laboratory, and if there is the presence of the bacteria, the result is positive.


Aside from rest, there is a need to treat a strep throat with antibiotics. This is because there are potentially serious complications associated with the disease. To reduce the risk of these complications, especially among children, the doctor will prescribe an antibiotic.

The common antibiotics prescribed by a licensed doctor may include:

  • Penicillin V
  • Amoxicillin
  • Penicillin G benzathine
  • Erythromycin ethyl succinate

A licensed doctor only prescribes These medications. Do not self-medicate. Moreover, be sure to finish the course of the antibiotics to reduce the risk of resistance to these medicines. Antibiotic resistance may lead to more serious health concerns.

Other Medicines

The doctor may also prescribe other medicines for symptom relief:

  • A cough and cold medicines
  • Salt water gargle
  • Pain relievers
  • Throat lozenges


As the famous adage goes, prevention is better than cure. It is important to manage a strep throat by preventing its spread to other people. Likewise, protecting oneself is also necessary.

  • Practice frequent handwashing after coughing or sneezing
  • Avoid close physical contact with people who have a strep throat
  • Cover the mouth and nose with tissue when coughing or sneezing
  • Avoid sharing food, drinks, and utensils with someone who has an active infection
  • If a strep infection is confirmed, the patient should stay inside the house within 24 hours of starting the antibiotics.
  • It is important to live a healthy lifestyle by eating a well-balanced diet rich in vitamins and minerals, drinking adequate amounts of water, exercising regularly, and keeping the household clean.


Usually, the symptoms of a strep throat infection improve within three to five days, whether there is a treatment or not. However, the use of antibiotics is important because they help reduce the risk of complications and transmission of the disease. For children, they can resume their classes in school after 24 hours of consuming their antibiotics.

The risk of complications among adults is low. However, for those people who belong to vulnerable groups, like infants, young children, pregnant women, older adults and those with weakened immune systems, are more prone to developing complications.