Strep throat: Causes, diagnosis, and treatments
"Sore throat" is the general term for any condition where the throat feels scratchy, tender, and possibly painful. Strep throat, however, is a sore throat caused by a specific strain of bacteria.
In this article, we will cover the causes, symptoms, diagnosis, and treatment of strep throat.
Here are some key points about strep throat. More detail and supporting information is in the main article.
- Strep throat is caused by group A streptococcus bacteria.
- Streptococcal bacteria are extremely contagious.
- Children are more susceptible than adults because their immune systems have had less experience of germs.
- If the sore throat is causing difficulty in breathing, seek medical help immediately.
- Diagnosis of strep throat often involves a throat swab.
What is strep throat?
Young boy with strep throat. Note the reddened soft palate at the back of the throat.
Strep throat may also be referred to as Streptococcal pharyngitis or streptococcal sore throat; it is only ever caused by bacteria.
Streptococcal bacteria are extremely contagious and can spread through airborne droplets when a sick person sneezes or coughs.
People may also become infected by touching surfaces that an infected person had previously touched, such as a doorknob, kitchen utensils, or bathroom objects.
Most sore throats are not usually serious, and the infected person generally improves within 3-7 days without treatment.
Sore throats are more common among children and adolescents; this is because younger people's bodies have not been exposed to as many viruses and bacteria as older people's - they have not built up immunity to many of them.
It is not uncommon for people of any age to have a couple of bouts of sore throat in a 1-year period.
Symptoms of strep throat
The symptoms of strep throat are similar to a sore throat; these include:
- Pain in the throat.
- Difficulty swallowing.
- Loss of appetite.
- Tonsils are painful and/or swollen; sometimes with white patches and/or streaks of pus.
- Very small red spots may appear on the soft part of the palate (roof of the mouth).
- Nodes (lymph glands) of the neck are swollen and tender.
Conversely, people with strep throat may sometimes have no signs or symptoms - these people might not feel ill, but they can still pass the infection onto other people.
When to see a doctor
In most cases, a sore throat is just one of the symptoms of a common cold and will resolve itself in a few days. However, you should see a doctor if:
- Symptoms are still there after a couple of weeks.
- Sore throats are frequent and do not respond to painkillers.
- There is persistent fever - this indicates an infection that should be diagnosed and treated as soon as possible. Infections may cause breathing problems or lead to complications.
- There are breathing difficulties (urgently).
- Swallowing saliva or fluids is difficult.
- Drooling becomes common.
- The immune system is weak - for instance with HIV/AIDS, diabetes, or anyone receiving chemotherapy, radiotherapy, steroids, or immunosuppressant medications.
- Urine becomes Cola-colored - this means the streptococcus bacteria has infected the kidneys.
Diagnosis of strep throat
Note the small red spots; these are known as petechiae.
The doctor will examine the patient and look for signs of strep throat or throat infection.
It is virtually impossible to know, initially, whether it is caused by a virus or bacteria. Some viral infections of the throat may have worse signs than those caused by streptococcal bacteria.
Consequently, the doctor may order one or more of the following tests to find out what is causing the infection:
- Throat culture - a swab is rubbed against the back of the throat and tonsils to test for the actual bacteria. It is not painful but may tickle, and the patient may have a temporary gagging sensation.
- Rapid antigen test - this test can detect strep bacteria in minutes from the swab sample by looking for antigens (parts of the bacteria) in the throat.
- Rapid DNA test - DNA technology is used to identify strep throat infection.
Treatment of strep throat
In most cases, sore throats do not require treatment and will resolve themselves within a week. OTC medication may help relieve symptoms. Some medications are available for purchase online, including aspirin, ibuprofen, or acetaminophen (Tylenol).
Patients with stomach or kidney problems should not take aspirin or ibuprofen. The following tips may also help manage a sore throat:
- Avoid foods or drinks that are very hot as they may irritate the throat.
- Cool drinks and cool soft foods can help relieve symptoms.
- Warm drinks (not hot) might also help.
- Smoking will irritate the throat, as will smoky environments.
- Sucking ice cubes can help symptoms (beware of giving them to young children).
- Gargling with mouthwash may reduce swelling and alleviate pain; slightly salted warm water is best.
Unless the patient has been diagnosed with a bacterial infection, antibiotics should not be used. In fact, experts say that even in the case of bacterial throat infections, antibiotics do not seem to be any more effective than normal pain-killing OTC medications.
One study suggests that treating coughs in children with honey may be a good alternative to cough medicines. However, honey should not be given to infants 12 months and under due to the risk of botulism (a type of food poisoning).
Antibiotics are generally only used when the chances are high that it is a bacterial infection. If the patient has a weak immune system, which raises the risk of complications from the infection, doctors may also treat with antibiotics without testing for bacteria. This may also be the case for patients with a history of heart disease or rheumatic fever. Patients who tend to get repeated bacterial throat infections may also be given antibiotics.
If strep throat is diagnosed with a rapid strep test or culture, a doctor will give antibiotics to clear the infection. In a very small percentage of people, the bacteria can cause rheumatic fever (bacterial particles affecting the heart) or kidney problems.
Tonsillectomy - if somebody, usually a child, has tonsillitis regularly (infection of the tonsils) a doctor may advise taking them out surgically (having a tonsillectomy).
Potential complications of strep throat
Sinusitis is a possible complication of strep throat.
Strep throat is easy to treat; however, if it is left, there is a chance it may lead to complications, these can include:
- Sinusitis - infection of the sinuses.
- The infection may travel to the ear, skin, or blood.
- Mastoiditis - an infection of the mastoid, a part of the skull behind the jaw.
- Rheumatic fever - an inflammatory disease.
- Peritonsillar abscess - a pus-filled pocket near the tonsils.
- Scarlet fever - caused by bacterial toxins; produces a scarlet rash.
- Guttate psoriasis - a type of psoriasis more common in children.
- Poststreptococcal glomerulonephritis - inflammation of the kidneys.
Prevention of strep throat
Many doctors say there is not much we can do to prevent sore throats that are caused by bacterial or viral infections. The following tips may help reduce the frequency of sore throats, and probably help prevent complications:
- Nutrition - a well-balanced diet, rich in fruit and vegetables, whole grains, good quality fats (olive oil, avocado, etc.) and lean proteins will boost the immune system.
- Exercise - regular exercise helps the immune system.
- Get plenty of sleep - without enough sleep the immune system will eventually become weaker.
- Don't smoke - people who smoke have significantly more bouts of sore throat compared to people who don't; they are also more susceptible to throat complications.
- Keep hands clean - regular hand washing with soap and water is an effective way of preventing most infections.
- Cover the mouth when coughing - this protects other people. Coughing into the inside of the elbow, rather than into the hands, also makes it less likely that surfaces will become contaminated when touched.
- Isolate personal items - drinking glasses and eating utensils, for example, should not be shared if they have been used by somebody who has a sore throat.
We picked linked items based on the quality of products, and list the pros and cons of each to help you determine which will work best for you. We partner with some of the companies that sell these products, which means Healthline UK and our partners may receive a portion of revenues if you make a purchase using a link(s) above.