Strep throat is a sore throat caused by bacteria known as Streptococcus pyogenes, or group A streptococcus. Sore throat is a term for any situation where the throat feels scratchy, tender, and possibly painful. Strep throat is a type of sore throat. Sore throat may be caused by bacteria or viruses, while strep throat is only caused by bacteria. The term strep throat is more commonly used in the USA and Canada, compared to other English speaking countries. Strep throat may also be referred to as Streptococcal pharyngitis or streptococcal sore throat.
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 which an infected person had previously touched, such as a doorknob, kitchen utensils and bathroom objects.
Most sore throats are not usually serious and the infected person generally improves within three to seven days without treatment. They 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 one-year period.
What are the causes of sore throat?
The following conditions generally include a sore throat. These conditions are usually caused by an infection:
Sore throat is usually caused by inflammation (swelling) in the back of the throat (oropharynx) and tonsils (laryngeal lymphoid nodules).
Infections can be caused by the streptococcus bacteria (causing strep throat) or viruses. However, sore throats can also be caused by the following non-infectious factors (less common):
Tiredness (probably an infection, possibly other reasons)
What are the signs and symptoms of strep throat?
Strep throat is an infection, while sore throat may or may not be. The signs and symptoms below refer just to strep throat:
Pain in the throat.
Tonsils are painful and/or swollen. Sometimes with white patches, and/or streaks of pus.
Very small red sports may appear on the soft part of the palate (roof of the mouth).
Nodes (lymph glands) of the neck are swollen and tender.
Stomachache. Children may have nausea and vomiting.
Although these symptoms are typical of strep throat, they could also be caused by a virus,
tonsillitis or some other illness. However, a doctor should be consulted if the symptoms and signs are present - especially a fever. Conversely, people with strep throat may sometimes have no signs or symptoms - these people might not feel ill, but can pass the infection onto other people.
When should you 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.
You have a persistent fever. A fever indicates an infection which should be treated and diagnosed as soon as possible. Infections may cause breathing problems, or may lead to complications.
You have breathing difficulties (urgently).
You find it hard to swallow saliva or fluids.
You start drooling.
If your immune system is weak - as might be the case for patients with HIV/AIDS, Diabetes, or those receiving chemotherapy, radiotherapy, steroids, immunosuppressant medications, DMARDs (disease-modifying anti-rheumatic medications), or antithyroids.
Coca-cola colored urine. This means the streptococcus bacteria has infected the kidneys.
Diagnosis of sore throat
A clinical diagnosis of sore throat is not generally needed if a person has sore throat. This will change if symptoms persist for more than a couple of weeks. A doctor will ask the patient about his/her symptoms, check for signs (examine the throat and neck). If the doctor suspects the patient may have glandular fever he/she may order a blood test.
Diagnosis of strep throat or throat infection
The doctor will examine the patient and look for signs of strep throat or throat infection. He/she will ask the patient for symptoms (a symptom is what the patient feels and describes to the doctor, a sign is what the doctor can see or feel).
Even if a doctor detects signs of an indication it is virtually impossible to know at this stage whether it is caused by 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. It is not painful but may tickle and the patient may have a temporary gagging sensation. Lab results may take a couple of days to come back.
Rapid antigen test - this test can detect strep bacteria in minutes from the swab sample by looking for antigens (foreign substances) in the throat. Rapid antigen tests are not as accurate as throat cultures that are sent to the lab - they may not detect some strep infections. That is why some doctors perform both tests.
Rapid DNA test - DNA technology is used to identify strep throat infection. Results take up to a day to come back. They are very accurate and much faster than throat culture tests.
What is the treatment for sore throat?
In most cases sore throats do not require treatment and will resolve themselves on their own within a week. OTC (over-the-counter, no prescription required) medication may help relieve symptoms, such as aspirin, ibuprofen or paracetamol (Tylenol). Patients with stomach or kidney problems should not take aspirin. In Europe children under 16 should not take aspirin.
The following may also help people with sore throat:
Foods or drinks that are very hot may irritate the throat.
Cool drinks and cool soft foods may help relieve symptoms.
Warm drinks (not hot) may also help relieve symptoms.
Sucking ice cubes may help symptoms (beware of giving them to very young children).
Smoking will irritate the throat, as will smoky environments.
Gargling with a 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 painkilling OTC medications. Doctors in the USA are much more likely to prescribe antibiotics for sore throat among children earlier on, compared to West European doctors (The UK appears to have the same problem as the USA in this case).
This report explains that antibiotic prescribing for sore throat among children in the USA is too high. This may be one of the reasons why superbugs (
MRSA) and hospital-acquire infections are a much bigger problem in the USA.
This study explains that with acute sore throat, antibiotics should normally
not be started immediately.
About 14 percent of U.S. children visit a health professional at least once a year for serious sore throat, and over two-thirds of these are prescribed antibiotics,
another report revealed.
Codeine and several cough remedies have been found to be ineffective against coughs (coughing may make sore throats feel worse).
This article revealed that codeine is no more effective than a placebo for treating coughs.
While recent guidelines have told parents not to use OTC cough medicines for young children,
several reports seem to indicate that they are not any good for older children and adults either.
Antibiotics are generally only used when the throat infection is severe, or if the patient has a weak immune system, which raises the risk of complications from the infection. 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.
Tonsillectomy - if somebody, usually a child, often has tonsillitis (infection of the tonsils) a doctor may advise taking them out surgically (having a tonsillectomy).
See this interesting 7-step guide to understanding tonsils and strep.
This article explains that adults with recurrent sore throats may benefit from having a tonsillectomy in the short term, but the overall longer term benefit is still unclear.
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 your immune system.
Exercise - regular exercise helps the immune system.
Get plenty of sleep - if you do not get enough sleep each night your 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, as well as being more susceptible to throat complications.
Keep your hands clean - regular hand washing with soap and water is a considerably 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.
Flu vaccine - this will significantly reduce the frequency of flu, as well as lowering the severity. Symptoms of flu include sore throat.