Streptococcal sore throat (strep throat), is an infection of the mucous membranes lining the throat. Sometimes the tonsils are also infected (tonsillitis).
Caused by group A Streptococcus bacteria, untreated strep throat may develop into rheumatic fever or other serious conditions.
Strep throat accounts for between 5% and 10% of all sore throats. It occurs most often between November to April, and while anyone can get strep throat, it's most common among school children. People who smoke or who are tired, rundown, or who live in damp, crowded conditions are more likely to become infected. Children under age 2 and adults who aren't around children are less likely to get the disease.
The disease passes directly from person to person by coughing or sneezing; rarely the bacteria is passed through food if a sick food handler accidentallycontaminates food by coughing or sneezing. Statistically, if someone in the home is infected, one out of every four other household members may get strepthroat within two to seven days.
A person with strep throat suddenly develops a painful sore throat one to five days after being exposed to the streptococcus bacteria. Unfortunately, it'simpossible to tell the difference between a sore throat caused by strep or by other bacteria or viruses. The infected person usually feels tired and hasa fever, sometimes accompanied by chills, headache, muscle aches, swollen lymph glands, and nausea. Young children may complain of abdominal pain. The tonsils look swollen and are bright red, with white or yellow patches of pus onthem. Sometimes the roof of the mouth is red or has small red spots. Often aperson with strep throat has bad breath.
Despite these common symptoms, strep throat can be deceptive. It's possible to have the disease and not show any of these symptoms. Many young children complain only of a headache and stomachache, without the characteristic sore throat.
There are complications. Occasionally, within a few days of developing the sore throat, a person may develop a fine, rough, sunburn-like rash over the face and upper body, together with a fever of between 101-104°F. The tonguebecomes bright red, with a flecked, strawberry-like appearance. When a rash develops, this form of strep throat is called scarlet fever. The rash is a reaction to toxins released by the streptococcus bacteria. Scarlet fever is no more dangerous than strep throat, and is treated the same way. The rash disappears in about five days. One to three weeks later, patches of skin may peel off, especially on the fingers and toes.
Untreated strep throat can cause rheumatic fever. This is a serious illness,although it occurs rarely. The most recent outbreak appeared in the United States in the mid-1980s. Rheumatic fever occurs most often in children betweenthe ages of five and 15, and may have a genetic component, since it seems torun in families. Although the strep throat that causes rheumatic fever is contagious, rheumatic fever itself is not.
Rheumatic fever begins one to six weeks after an untreated streptococcal infection. The joints, especially the wrists, elbows, knees, and ankles become red, sore, and swollen. The infected person develops a high fever, and possiblya rapid heartbeat when lying down, paleness, shortness of breath, and fluidretention. A red rash over the trunk may come and go for weeks or months. Anacute attack of rheumatic fever lasts about three months. Rheumatic fever cancause permanent damage to the heart and heart valves. It can be prevented bypromptly treating streptococcal infections with antibiotics. It does not occur if all the streptococcus bacteria are killed within the first 10-12 days after infection.
In the 1990s, outbreaks of a virulent strain of group A Streptococcuswere reported to cause a toxic shock-like illness and a severe invasive infection called necrotizing fasciitis, which destroys skin and muscle tissue. Although these diseases are caused by group A Streptococci, they rarelybegin with strep throat. Instead, in these cases the streptococcus bacteria enters the body through a skin wound. These complications are rare. However, since the death rate in necrotizing fasciitis is 30% to 50%, it's a good ideato seek prompt treatment for any streptococcal infection.
A doctor diagnoses strep throat by conducting a physical examination of the throat and chest. The doctor will also look for signs of other illness, such as a sinus infection or bronchitis, and ask if the patient has been around other people with strep throat. If it appears that the patient may have strep throat, the doctor will do laboratory tests.
There are two types of tests to determine if a person has strep throat: a rapid strep test or a throat culture. For both, a nurse will use a sterile swabto reach down into the throat and obtain a sample of material from the sore area. The procedure takes only a few seconds, but may cause gagging.
A rapid strep test can only determine the presence of streptococcal bacteria,but will not tell if the sore throat is caused by another kind of bacteria;these results are available in about 20 minutes. The advantage of this test is the speed with which a diagnosis can be made. However, in about 20% of cases where no strep is detected by the rapid test, the patient actually does have strep throat. Because of this, when the rapid strep test is negative, a doctor often does a throat culture.
For a throat culture, a sample of swabbed material is grown in the lab so that technicians can determine what kind of bacteria are present. Results take 24 to 48 hours. The test is very accurate and will show the presence of otherkinds of bacteria besides Streptococci.
It's important not to take any antibiotics before having a throat culture, since even small amounts of antibiotics can mask the presence of the bacteria.
In the event that rheumatic fever is suspected, the doctor can do a blood test. This test, called an antistreptolysin-O test, will tell the doctor whetherthe person has recently been infected with strep bacteria. This helps the doctor distinguish between rheumatic fever and rheumatoid arthritis.
Strep throat is treated with antibiotics. Penicillin is the preferred medication. Oral penicillin must be taken for 10 days. Patients need to take the entire amount of antibiotic prescribed and not discontinue taking the medicationwhen they feel better. Stopping the antibiotic early can lead to a return ofthe strep infection. Occasionally, a single injection of long-acting penicillin (Bicillin) is given instead of 10 days of oral treatment.
About 10% of the time, penicillin doesn't kill the strep bacteria. When thishappens a doctor may prescribe other antibiotics such as amoxicillin (Amoxil), clindamycin (Cleocin), or a cephalosporin (such as Ceclor). Erythromycin, another relatively inexpensive antibiotic, is given to people who are allergicto penicillin. Scarlet fever is treated with the same antibiotics as strep throat.
Without treatment, the symptoms of strep throat begin subsiding in four or five days. However, because of the possibility of getting rheumatic fever, it'simportant to treat strep throat promptly. If rheumatic fever does occur, it's also treated with antibiotics. Anti-inflammatory drugs are used to treat joint swelling, and diuretics are used to reduce water retention. Once the rheumatic fever becomes inactive, children may continue on low doses of antibiotics to prevent a reoccurrence. Necrotizing fasciitis is treated with intravenous antibiotics.
There are some steps that people can take to ease the discomfort of their strep symptoms.
- Take acetaminophen or ibuprofen for pain. Aspirin shouldnot be given to children because of its association with an increase in Reye's syndrome, a serious disease.
- Gargle with warm double strength teaor warm salt water (one teaspoon of salt to eight ounces of water) to relievesore throat pain.
- Drink plenty of fluids, but avoid acidic juices like orange juice because they irritate the throat.
- Eat soft, nutritious foods like noodle soup. Avoid spicy foods.
- Avoid smoke and smoking.
- Rest until the fever is gone, then resume strenuous activities gradually.
- Use a room humidifier, as it may make sore throat sufferers more comfortable.
- Antiseptic lozenges and sprays may aggravate the sorethroat rather than improve it.
It's possible also to ease the symptoms of strep throat by using various herbs and natural treatments. Some practitioners suggest using these treatments in addition to antibiotics, since they primarily address the comfort of the patient and not the underlying infection. Many practitioners recommend Lactobacillus acidophilus to offset the suppressive effects of antibiotics onthe helpful bacteria of the intestines. Other suggested treatments include:
- Inhaling fragrances of the essential oils of lavender, thyme, eucalyptus, sage, or sandalwood
- Gargling with a mixture of water, salt, and tumeric powder or astringents, such as alum, sumac, sage, and bayberry
- Drinking tea made of sage or echinacea
Patients with strep throat begin feeling better -- and are no longer contagious -- 24 hours after starting antibiotics. Symptoms rarely last longer than five days. Children should not return to school or childcare until they are nolonger contagious. Food handlers should not work for the first 24 hours after antibiotic treatment, because strep infections are occasionally passed through contaminated food. People who are not treated with antibiotics can continue to spread strep bacteria for several months.
About 10% of strep throat cases don't respond to penicillin. People who haveeven a mild sore throat after a 10-day treatment with antibiotics should return to their doctor. It's possible that the patient is just a carrier of strep, and that something else is causing the sore throat.
Taking antibiotics within the first week of a strep infection will prevent rheumatic fever and other complications. If rheumatic fever does occur, the outcomes vary considerably: Some people may be cured, but others may have permanent damage to the heart and heart valves. In rare cases, rheumatic fever canbe fatal.
Necrotizing fasciitis has a death rate of 30% to 50%. Patients who survive often suffer a great deal of tissue and muscle loss. Fortunately, this complication of a streptococcus infection is very rare.
There is no way to prevent getting a strep throat. However, the risk of getting one or passing one on to another person can be minimized by:
- Washing hands often and well, especially after nose blowing or sneezing and beforehandling food
- Disposing of used tissues properly
- Avoiding close contact with someone who has a strep throat
- Not sharing food and eating utensils with anyone
- Not smoking.