Strep Throat

Definition

Streptococcal sore throat, or strep throat as it is more commonly called, is an infection of the mucous membranes lining the pharynx. Sometimes the tonsils are also infected (tonsillitis ). The disease is caused by group A Streptococcus bacteria. Untreated strep throat may develop into rheumatic fever or other serious conditions.

Description

Strep throat accounts for between 5-10% of all sore throats. Although anyone can get strep throat, it is most common in school-age children. People who smoke, who are fatigued, run down, or who live in damp, crowded conditions are also more likely to become infected. Children under age two and adults who are not around children are less likely to get the disease.

Strep throat occurs most frequently from November to April. The disease passes directly from person to person by coughing, sneezing, and close contact. Very occasionally the disease is passed through food, when a food handler infected with strep throat accidentally contaminates food by coughing or sneezing. Statistically, if someone in the household is infected, one out of every four other household members may get strep throat within two to seven days.

Causes and symptoms

A person with strep throat suddenly develops a painful sore throat one to five days after being exposed to the streptococcus bacteria. The pain is indistinguishable from sore throats caused by other diseases.

The infected person usually feels tired and has a 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 on them. Sometimes the roof of the mouth is red or has small red spots. Often a person with strep throat has bad breath.

Despite these common symptoms, strep throat can be deceptive. It is 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.

Occasionally, within a few days of developing the sore throat, an individual may develop a fine, rough, sunburn-like rash over the face and upper body, and have a fever of 101-104°F (38.3-40°C). The tongue becomes 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, as might occur with a sunburn, 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 between the ages of five and 15, and may have a genetic component, since it seems to run 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 possibly a rapid heartbeat when lying down, paleness, shortness of breath, and fluid retention. A red rash over the trunk may come and go for weeks or months. An acute attack of rheumatic fever lasts about three months.

Rheumatic fever can cause permanent damage to the heart and heart valves. It can be prevented by promptly 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 Streptococcus were 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 rarely begin with strep throat. Usually the streptococcus bacteria enters the body through a skin wound. These complications are rare. However, since the death rate in necrotizing fasciitis is 30-50%, it is wise to seek prompt treatment for any streptococcal infection.

Diagnosis

Diagnosis of a strep throat by a doctor begins with 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 seek information about whether 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 can only determine the presence of streptococcal bacteria, but will not tell if the sore throat is caused by another kind of bacteria. The results are available in about 20 minutes. The advantage of this test is the speed with which a diagnosis can be made.

The rapid strep test has a false negative rate of about 20%. In other words, in about 20% of cases where no strep is detected by the rapid strep test, the patient actually does have strep throat. Because of this, when a rapid strep test is negative, the doctor often does a throat culture.

For a rapid strep test or a throat culture, a nurse will use a sterile swab to 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.

For a throat culture a sample of swabbed material is cultured, or grown, in the laboratory on a medium that allows technicians to determine what kind of bacteria are present. Results take 24-48 hours. The test is very accurate and will show the presence of other kinds of bacteria besides Streptococci. It is important not to take any leftover antibiotics before visiting the doctor and having a throat culture. Even small amounts of antibiotics can suppress the bacteria and mask its presence in the throat culture.

In the event that rheumatic fever is suspected, the doctor does a blood test. This test, called an antistreptolysin-O test, will tell the doctor whether the person has recently been infected with strep bacteria. This helps the doctor distinguish between rheumatic fever and rheumatoid arthritis.

Treatment

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 medication when they feel better. Stopping the antibiotic early can lead to a return of the 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 is not effective against the strep bacteria. When this happens a doctor may prescribe other antibiotics such as amoxicillin (Amoxil, Pentamox, Sumox, Trimox), clindamycin (Cleocin), or a cephalosporin (Keflex, Durocef, Ceclor). Erythromycin (Eryzole, Pediazole, Ilosone), another inexpensive antibiotic, is given to people who are allergic to 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 is important to treat strep throat promptly with antibiotics. If rheumatic fever does occur, it is also treated with antibiotics. Anti-inflammatory drugs, such as steroids, are used to treat joint swelling. 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.

Home care for strep throat

There are home care steps that people can take to ease the discomfort of their strep symptoms.

• Take acetaminophen or ibuprofen for pain. Aspirin should not be given to children because of its association with an increase in Reye's Syndrome, a serious disease.
• Gargle with warm double strength tea or warm salt water, made by adding one teaspoon of salt to eight ounces of water, to relieve sore 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.
• Be aware that antiseptic lozenges and sprays may aggravate the sore throat rather than improve it.

Alternative treatment

Alternative treatment focuses on easing the symptoms of strep throat through herbs and botanical medicines. 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 on the beneficial bacteria of the intestines.

Some suggested treatments include:

• Inhaling fragrances of the essential oils of lavender (Lavandula officinalis ), thyme (Thymus vulgaris ), eucalyptus (Eucalyptus globulus ), sage (Salvia officinalis ), and sandalwood (Aromatherapy).
• Gargling with a mixture of water, salt, and tumeric (Curcuma longa ) powder or astringents, such as alum, sumac, sage, and bayberry (Ayurvedic medicine).
• Taking osha root (Ligusticum porteri ) internally for infection or drinking tea made of sage, echinacea (Echinacea spp.) and cleavers (Gallium aparine ) Osha root has an unpleasant taste many children will not accept (Botanical medicine).

Prognosis

Patients with strep throat begin feeling better about 24 hours after starting antibiotics. Symptoms rarely last longer than five days.

People remain contagious until after they have been taking antibiotics for 24 hours. Children should not return to school or childcare until they are no longer 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 do not respond to penicillin. People who have even a mild sore throat after a 10 day treatment with antibiotic should return to their doctor. An explanation for this may be that the person 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 cases may be cured. In others there may be permanent damage to the heart and heart valves. In rare cases, rheumatic fever can be fatal.

Necrotizing fasciitis has a death rate of 30-50%. Patients who survive often suffer a great deal of tissue and muscle loss. Fortunately, this complication of a streptococcus infection is very rare.

Prevention

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:

• sashing hands well and frequently, especially after nose blowing or sneezing and before food handling
• 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

KEY TERMS

Lactobacillus acidophilus — A bacteria found in yogurt that changes the balance of the bacteria in the intestine in a beneficial way.

Resources

OTHER

"Group A Streptococcal Infections." National Institute of Allergy and Infectious Diseases Page. February 22, 1998. 〈http://www.niaid.nih.govfactsheets/strep.htm〉.

Strep Throat

Definition

Strep throat is an infection of the mucous membranes lining the pharynx. Sometimes the tonsils are also infected (tonsillitis). The infection is caused by group A beta-hemolytic Streptococcusbacteria, commonly known as strep.

This bacterial infection typically causes a severe sore throat, fever, and difficulty swallowing. Strep throat may also produce a rash, known as scarlet fever, and swollen glands. Untreated, it can lead to rheumatic fever, a serious kidney disorder called glomerulonephritis, and other infections.

Description

Strep throat accounts for 5-10% of all sore throats. Although anyone can get strep throat, it is most common in school-age children. It accounts for about one quarter of sore throats in children ages five to 15. Smokers, and people who are fatigued, immunosuppressed, or who live in damp, crowded conditions are more likely to become infected. Children under age two and adults who do not have contact with children are less likely to become infected.

Strep throat occurs most frequently from November to April. The disease passes directly from person to person by coughing, sneezing, and close contact. Rarely, it may be passed through food, when a food handler infected with strep throat accidentally contaminates food by coughing or sneezing. Statistically, when one member of a household is infected, one out of every four other household members will contract strep throat within two to seven days.

Causes and symptoms

Strep infection may produce a sudden, painful sore throat one to five days after exposure to the Streptococcus bacteria. The pain is indistinguishable from sore throats caused by viral infections.

The infected patient usually feels tired and has a fever, sometimes accompanied by chills, headache, muscle aches, swollen lymph glands, and nausea. Young children may complain of abdominal pain. The tonsils appear swollen and are bright red, and may have white or yellow patches of pus. Sometimes the roof of the mouth is red or has small red spots. Often a person with strep throat has bad breath.

Though most patients display some of these common symptoms, it is possible to have the disease without any of these symptoms. Many young children complain only of a headache and stomachache, rather than the characteristic sore throat.

Occasionally, within a few days of developing the sore throat, patients may develop a fine, rough, sunburn-like rash over the face and upper body, along with a fever of 101-104 °F (38.3-40 °C) and bright red tongue, with a flecked, strawberry-like appearance. When a rash develops, this form of strep throat is called scarlet fever. The rash is caused by 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 desquamate (peel off), as might occur with a sunburn.

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 between the ages of five and 15, and susceptibility to it may be genetic, since it seems to run 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 patient develops a high fever, and possibly a rapid heartbeat when lying down, paleness, shortness of breath, and fluid retention. A red rash over the trunk may come and go for weeks or months. An acute attack of rheumatic fever lasts about three months.

Rheumatic fever can cause permanent damage to the heart and heart valves. It can be prevented by promptly treating streptococcal infections with antibiotics. It does not occur if all the streptococcus bacteria are killed within the first 10-12 days after infection.

During the 1990s, outbreaks of a virulent strain of group A Streptococcus were 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 rarely begin with strep throat. Usually the streptococcus bacteria enter the body through a skin wound. These infections are rare; however, since the death rate in necrotizing fasciitis is 30-50%, it is wise to promptly treat any streptococcal infection.

Diagnosis

Diagnosis of strep throat begins with a physical examination of the throat. The doctor will also look for signs of other illness, such as a sinus infection or bronchitis, and seek information about whether the patient has been exposed to anyone with strep throat. Patients likely to have strep throat will have a rapid strep test or throat culture, laboratory tests to detect the presence of bacteria.

There are two types of tests to confirm the diagnosis of strep throat. A rapid strep test determines the presence of streptococcal antigen, and results are available in about 20 minutes. The advantage of this test is the speed with which a diagnosis may be made.

The rapid strep test has a false negative rate of about 20%. For this reason, when a rapid strep test is negative, the physician may order a throat culture.

For a rapid strep test or a throat culture, a physician, mid-level practitioner (i.e., nurse practitioner or physician assistant) or nurse will use a sterile swab to reach down into the throat to obtain a sample of material from the sore area. The procedure takes only a few seconds, but may cause some patients to gag.

For a throat culture, a sample of swabbed material is cultured, or grown, in the laboratory on a medium that allows laboratory technologists and technicians to accurately determine whether group A Streptococci is present. Results are available in 24-48 hours. This test is very accurate and also detects the presence of bacteria other than Streptococci. Patients should be reminded by the nurse not to take antibiotics before a throat culture. Even small amounts of antibiotics can suppress the bacteria enough to mask their presence in the throat culture.

In the event that rheumatic fever is suspected, the physician will order a blood test. This test, called an antistreptolysin-O test, determines whether the person has recently been infected with strep bacteria and helps to distinguish between rheumatic fever and rheumatoid arthritis.

Treatment

Strep throat is treated with antibiotics. Penicillin is the preferred medication. The typical dose for adults is Penicilin V, 250 mg by mouth, four times a day or 500 mg twice a day. Alternatively, 250 mg of erythromycin may be given four times a day. Oral antibiotics must be taken for 10 days. Patients must be advised to take the entire amount of antibiotic prescribed. They must be warned not to discontinue taking the medication when they feel better. Stopping the antibiotic early or failing to complete the prescribed course of medication can lead to a return of the strep infection. Occasionally, a single injection of benzathine penicillin G 1.2 million units IM (intramuscularly) is given instead of 10 days of oral treatment.

About 10% of the time, penicillin is not effective against the strep bacteria. In such instances, other antibiotics such as amoxicillin (Amoxil, Pentamox, Sumox, Trimox), clindamycin (Cleocin), or a cephalosporin (Keflex, Durocef, Ceclor) may be prescribed. Erythromycin (Eryzole, Pediazole, Ilosone), another inexpensive antibiotic, is given to patients who are allergic to 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 contracting rheumatic fever, glomerulonephritis, or other infections, it is vital to treat strep throat promptly with antibiotics. If rheumatic fever does occur, it also is 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.

Home care for strep throat

Patients may be taught home care measures to relieve the discomfort of their strep symptoms. They may be counseled by the nurse, mid-level practitioner, or physician to:

• Take acetaminophen or ibuprofen for pain. Aspirin should not be given to children because of its association with Reye's syndrome.
• Gargle with warm double strength tea or warm salt water, made by adding one teaspoon of salt to eight ounces of water, to relieve sore 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.
• Be aware that antiseptic lozenges and sprays may aggravate the sore throat rather than improve it.

Alternative treatment focuses on easing the symptoms of strep throat through herbs and botanical medicines. Honey, eucalyptus, and menthol-infused drops and syrups may all soothe the soreness of strep throat. These treatments should never be used in place of antibiotic therapy. They should be used in addition to antibiotics, since they address symptoms rather than the underlying infection.

Prognosis

Patients with strep throat begin feeling better about 24 hours after starting antibiotics. Symptoms rarely last longer than five days.

Patients remain contagious until they have taken antibiotics for 24 hours. Children should not return to school or childcare until they are no longer 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 do not respond to penicillin. Patients with even a mild sore throat after a 10 days of antibiotic treatment should be advised to return to the doctor. One explanation for a persisting sore throat may be that the patient is simply a carrier of strep, and the sore throat is the result of another infectious (bacterial or viral) agent.

Timely administration of antibiotics within the first week of a strep infection acts to prevent rheumatic fever and other complications. If rheumatic fever does occur, the outcomes vary considerably. Some cases may be cured; others cause permanent damage to the heart and heart valves. In rare cases, rheumatic fever can be fatal.

Necrotizing fasciitis has mortality (death rate) of 30-50%. Patients who survive often suffer a great deal of tissue and muscle loss. Fortunately, this complication of a Streptococcus infection is very rare.

Health care team roles

Physicians, nurses, mid-level practitioners, and laboratory technologists are involved in the diagnosis and treatment of strep throat. In contacts with patients they can reinforce the value of adherence to prescribed treatment and can instruct patients in selfcare and home care measures to relieve symptoms.

Patient education

Nurses, mid-level practitioners, and laboratory personnel have opportunities to teach patients how to minimize the risks of transmission by reinforcing the importance of personal hygiene, safe food handling, and avoiding exposures. They must also emphasize the importance of prompt and complete treatment of strep infection to prevent consequences and recurrence.

Prevention

There is no way to prevent getting a strep throat. Patients may be counseled about how to reduce the risk of transmission. Risk may be minimized by:

• washing hands well and frequently, especially after nose blowing or sneezing and before food handling
• 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

KEY TERMS

Desquamate— To peel off or exfoliate the skin.

Glomerulonephritis— A serious kidney disorder that sometimes results from an untreated strep infection.

Lactobacillus acidophilus— A bacteria found in yogurt that changes the balance of the bacteria in the intestine in a beneficial way.

Resources

BOOKS

Professional Guide to Diseases, 5th edition. Springhouse, PA: Springhouse Corp., 1995.

The Washington Manual of Medical Therapeutics, 30th edition. Philadelphia, PA: Lippincott Williams & Wilkins., 2001, pp. 304.

OTHER

National Institute of Allergy and Infectious Diseases. "Group A Streptococcal Infections." NIAID Fact Sheet. (February 1998). 〈http://www.niaid.nih.govfactsheets/strep.htm〉.

Strep throat

Definition

Streptococcal sore throat , or strep throat, as it is more commonly called, is a bacterial infection of the mucous membranes lining the throat or pharynx.

Description

Strep throat is caused by a type of bacteria called group A streptococci. The tonsils may also become infected (tonsillitis ). Left untreated, strep throat may develop into rheumatic fever or other serious conditions.

Demographics

Strep throat accounts for between 5 and 10 percent of all sore throats. Although anyone can get strep throat, it is most common in school-age children. People who smoke, who are fatigued, run down, or who live in damp, crowded conditions are also more likely to become infected. Children under age two and adults who are not around children are less likely to get the disease.

Strep throat occurs most frequently between November to April. The disease passes directly from person to person by coughing, sneezing, and close contact. On rare occasions, the disease is passed through food, when a food handler infected with strep throat accidentally contaminates food by coughing or sneezing. Statistically, if someone in the household is infected, one out of every four other household members may get strep throat within two to seven days.

Causes and symptoms

A person with strep throat suddenly develops a painful sore throat one to five days after being exposed to the streptococcus bacteria. The pain is indistinguishable from sore throats caused by other diseases.

The infected person usually feels tired and has a 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 on them. Sometimes the roof of the mouth is red or has small red spots. Often a person with strep throat has bad breath.

Despite these common symptoms, strep throat can be deceptive. It is 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.

Occasionally, within a few days of developing the sore throat, an individual may develop a fine, rough, sunburn-like rash over the face and upper body and have a fever of 101–104°F (38.3–40°C). The tongue becomes 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, as might occur with a sunburn , especially on the fingers and toes.

Untreated strep throat can cause rheumatic fever. This is a serious illness, although it occurs rarely. One outbreak appeared in the United States in the mid-1980s. Rheumatic fever occurs most often in children between the ages of five and 15 and may have a genetic component, since it seems to run 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 possibly a rapid heartbeat when lying down, paleness, shortness of breath, and fluid retention. A red rash over the trunk may come and go for weeks or months. An acute attack of rheumatic fever lasts about three months.

Rheumatic fever can cause permanent damage to the heart and heart valves. It can be prevented by promptly treating streptococcal infections with antibiotics . It does not occur if all the streptococcus bacteria are killed within the first ten to 12 days after infection.

In the 1990s, outbreaks of a virulent strain of group A streptococcus were 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 rarely begin with strep throat. Usually 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 percent, it is wise to seek prompt treatment for any streptococcal infection.

Diagnosis

Diagnosis of a strep throat by a doctor begins with 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 seek information about whether 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 can only determine the presence of streptococcal bacteria but will not tell if the sore throat is caused by another kind of bacteria. To perform a rapid strep test or a throat culture , a nurse will use a sterile swab to 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. The results are available in about 20 minutes. The advantage of this test is the speed with which a diagnosis can be made.

The rapid strep test has a false negative rate of about 20 percent. In other words, in about 20 percent of cases where no strep is detected by the rapid strep test, the patient actually does have strep throat. Because of this margin of error, when a rapid strep test is negative, the doctor often does a throat culture.

For a throat culture a sample of swabbed material is cultured, or grown, in the laboratory on a medium that allows technicians to determine what kind of bacteria are present. Results take 24 to 48 hours. The test is very accurate and will show the presence of other kinds of bacteria besides streptococci. It is important not to take any leftover antibiotics before visiting the doctor and having a throat culture. Even small amounts of antibiotics can suppress the bacteria and mask its presence in the throat culture.

In the event that rheumatic fever is suspected, the doctor does a blood test. Results of this test, called an antistreptolysin-O test, tell the doctor whether the person has recently been infected with strep bacteria. This information helps the doctor distinguish between rheumatic fever and rheumatoid arthritis.

Treatment

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 medication when they feel better. Stopping the antibiotic early can lead to a return of the strep infection. Occasionally, a single injection of long-acting penicillin (Bicillin) is given instead of ten days of oral treatment.

About 10 percent of the time, penicillin is not effective against the strep bacteria. When this happens a doctor may prescribe other antibiotics such as amoxicillin (Amoxil, Pentamox, Sumox, Trimox), clindamycin (Cleocin), or a cephalosporin (Keflex, Durocef, Ceclor). Erythromycin (Eryzole, Pediazole, Ilosone), another inexpensive antibiotic, is given to people who are allergic to 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 is important to treat strep throat promptly with antibiotics. If rheumatic fever does occur, it is also treated with antibiotics. Anti-inflammatory drugs, such as steroids, are used to treat joint swelling. 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.

Prognosis

Patients with strep throat begin feeling better about 24 hours after starting antibiotics. Symptoms rarely last longer than five days.

People remain contagious until after they have been taking antibiotics for 24 hours. Children should not return to school or childcare until they are no longer 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 percent of strep throat cases do not respond to penicillin. People who have even a mild sore throat after a 10-day treatment with antibiotic should return to their doctor. An explanation for this problem may be that the person 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 cases may be cured. In others there may be permanent damage to the heart and heart valves. In rare cases, rheumatic fever can be fatal.

Necrotizing fasciitis has a death rate of 30 to 50 percent. Patients who survive often suffer a great deal of tissue and muscle loss. Fortunately, this complication of a streptococcus infection is very rare.

Prevention

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 the following precautions:

• washing hands well and frequently, especially after nose blowing or sneezing and before food handling
• 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

Parental concerns

Children who have strep throat should be kept out of daycare, school, activities, and other public places until they have been taking their antibiotic for a full 24 hours. This will help decrease the likelihood of passing on the infection to others.

Parents who are caring for a child with strep will want to take the following steps:

• Give the child acetaminophen or ibuprofen for pain. Aspirin should not be given to children because of its association with Reye's syndrome , a serious disease.
• Encourage the child to gargle with warm double strength tea or warm salt water, made by adding one teaspoon of salt to eight ounces of water, to relieve sore throat pain.
• Make sure that the child drinks plenty of fluids but avoids acidic juices like orange juice because they irritate the throat.
• Offer the child soft, nutritious foods like noodle soup and avoid spicy foods.
• Help the child avoid exposure to people who are smoking.
• Encourage the child to rest until the fever is gone, then allow him or her to gradually resume activities.
• Use a room humidifier, as it may make sore throat sufferers more comfortable.
• Be aware that antiseptic lozenges and sprays may aggravate the sore throat rather than improve it.

KEY TERMS

Lactobacillus acidophilus —Commonly known as acidophilus, a bacteria found in yogurt that changes the balance of the bacteria in the intestine in a beneficial way.

Resources

BOOKS

Gerber, Michael A. "Group A Streptococcus." In Nelson Textbook of Pediatrics. Edited by Richard E. Behrman et al. Philadelphia: Saunders, 2004.

PERIODICALS

Ebell, M. H. "Strep Throat." American Family Physician 68 (September 1, 2000): 937–8.

Tish Davidson, A.M. Rosalyn Carson-DeWitt, MD

Strep throat

Definition

Strep throat is a contagious infection caused by the bacterium Streptococcus pyogenes.

Description

Strep throat primarily affects children, especially those between the ages of five and 15. Adults whose immune systems have been weakened by stress or other infections are also at risk. Most sore throats are associated with viral infections such as the common cold or the flu. Strep throat is responsible in only about 10%–15% of cases. Many people carry Streptococcus pyogenes in their systems without even knowing it. It can survive in the lining of the throat or nose for years without producing symptoms. Almost 20% of people in general good health may be harboring this bacterium unsuspectingly, according to one statistic.

Strep throat is often mistaken for a cold or the flu. It is important, however, to identify strep throat because if left untreated it can lead to serious health problems. In rare cases, untreated strep throat may increase the risk of developing scarlet or rheumatic fever . Rheumatic fever , in turn, is associated with meningitis and diseases affecting the heart, skin, kidneys, and joints. Strep throat may return repeatedly if not treated effectively the first time.

Another reason for getting treatment for strep throat is that Streptococcus pyogenes belongs to a group of diseasecausing bacteria that produce superantigens. Superantigens are a group of toxins that have the ability to trigger excessive and abnormal activation of the body's T cells. T cells are produced in the thymus gland and regulate the human immune system's response to infection. Superantigens are being studied intensively for their roles in causing disease. Streptococcus pyogenes and Staphylococcus aureus together produce 19 different superantigens.

Causes & symptoms

Most people develop strep throat through close contact with someone who has an untreated strep infection. Infected mucus from the nose or throat is often spread via sneezing or coughing. Carriers of Streptococcus pyogenes who do not show symptoms of strep throat are less likely to infect others, as are people with strep throat who have received antibiotic therapy for 24 hours or more. Strep throat is not usually transmitted through casual contact. In rare cases, strep can develop after exposure to infected food, dairy products, or water.

People with weakened immune systems are more likely to become infected with strep throat. This infection can occur when the body is battling a cold or the flu. Stress or physical exhaustion can also weaken the immune system and increase the risk of bacterial infection. Strep throat usually strikes during the winter months. Symptoms develop two to four days after being infected.

While cold or flu symptoms often develop gradually over a period of several days, the symptoms associated with strep throat occur with little warning. Classic symptoms of strep include sore throat and fever. Other tell-tale signs may include swollen and tender lymph glands in the neck, redness on the inside of the throat, inflamed tonsils or gray/white patches on the tonsils, and headache . Trouble swallowing can also occur, and red specks may be visible on the roof of the mouth. Nausea and stomach pain are more likely in children infected with strep. Unlike a cold or the flu, strep throat does not usually produce cough or a stuffy, runny nose.

Diagnosis

Most doctors who suspect strep throat recommend a rapid strep test to confirm the diagnosis. This painless

test involves using a swab to remove a specimen from the throat of the infected person. The results of the test are available in 10–20 minutes. In addition, the doctor may send a similar specimen to a laboratory to have a throat culture performed, which takes a day or two to complete. A negative strep test or culture usually indicates that the cause is viral in nature, in which case antibiotics are of no help.

Treatment

Conventional medicine is very successful in treating strep throat. However, several alternative therapies may help to resolve the disease or relieve symptoms. Herbal remedies such as echinacea (Echinacea spp.), goldenseal (Hydrastis canadensis ), and garlic (Allium sativum ) are believed to strengthen the immune system and combat bacterial infections.

Goldenseal

One of its active agents is a chemical called berberine. This alkaloid is believed to have antibiotic effects against streptococci bacteria. It may also help to prevent Streptococcus pyogenes from attaching itself to the throat lining, according to a study published in the journal Antimicrobial Agents and Chemotherapy in 1988. Goldenseal is also believed to increase the activity of disease-fighting white blood cells.

Echinacea

This popular herb fights viral and bacterial infections by boosting the immune system, according to herbalists. Echinacea may also combat strep throat by interfering with the production of hyaluronidase, an enzyme that helps the offending bacterium to grow and spread.

Garlic

The focus of hundreds of medical studies and papers, garlic is believed to be an antibiotic as well as an antiviral. As an added benefit, garlic may also prevent atherosclerosis , lower cholesterol levels, and act as an antioxidant.

Zinc and ginger (Zingiber officinale ) are sometimes recommended to help treat symptoms of sore throat. In addition to strengthening the immune system, zinc may reduce throat inflammation and pain regardless of the cause. Ginger may have analgesic properties and ease throat irritation.

In the practice of homeopathy, belladonna, lachesis , and mercurius are usually the remedies of choice for strep throat and other causes of throat irritation. Which remedy to use depends on the exact nature of the symptoms. These homeopathic treatments are not recommended for more than a few days or symptoms may actually return.

Vitamin C may also help to boost the immune system. In some studies, it has been shown to shorten the duration of colds.

Allopathic treatment

Antibiotics, the conventional treatment of choice, are very effective in curing strep throat. They also ease symptoms and are generally believed to reduce the risk of serious complications such as rheumatic fever. Ten days of oral penicillin is a typical course of therapy. People allergic to this drug usually take erythromycin instead. In some cases, a single injection of antibiotics may be preferred. It is important to complete the full course of antibiotic therapy (even if symptoms begin to subside earlier) in order to resolve the disease and prevent the development of complications. To further alleviate symptoms, acetaminophen or ibuprofen may also be used.

Studies of bacterial resistance to various drugs indicate that the strains of S. pyogenes found most commonly in the United States have developed some resistance to erythromycin as of 2002. As a result, doctors are more likely to prescribe antibiotics that belong to a newer group of drugs called quinolones. It is important to take quinolone antibiotics exactly as directed, as they have a number of side effects.

Expected results

The symptoms associated with strep throat usually begin to disappear within several days even without treatment. When antibiotics are used, fever may subside within 24 hours, and the course of the illness may be shortened by two days.

People who use alternative remedies in the absence of antibiotics should consult a doctor if symptoms do not subside within a week. In these cases, the use of antibiotics is strongly recommended.

Prevention

Washing the hands frequently can help to prevent strep throat. Exposure to infected people should also be avoided. In order to prevent transmission of the disease within households, consult a doctor if any family member suddenly develops a sore throat (especially if it is accompanied by fever).

Boosting the immune system is also important to help prevent the development of strep throat. Vitamin C and zinc are often recommended for this purpose, as are goldenseal, echinacea, and garlic. Reducing stress and getting proper sleep can also strengthen the body's defenses against infection.

Resources

BOOKS

Bennett, Claude J., and Fred Plum. Cecil Textbook of Medicine. Philadelphia, PA: W.B. Saunders Company, 1996.

Murray, Michael T., and Joseph Pizzorno. Encyclopedia of Natural Medicine. Rocklin, CA: Prima Publishing, 1998.

PERIODICALS

Barros, M.G. "Soothing Sore Throats Gingerly." Cortlandt Forum 67 (1995): 86-16.

Critchley, I. A., D. F. Sahm, C. Thornsberry et al. "Antimicrobial Susceptibilities of Streptococcus pyogenes Isolated from Respiratory and Skin and Soft Tissue Infections: United States LIBRA Surveillance Data from 1999." Diagnostic Microbiology and Infectious Disease 42 (February 2002): 129-135.

Llewelyn, M., and J. Cohen. "Superantigens: Microbial Agents That Corrupt Immunity." Lancet Infectious Diseases 2 (March 2002): 156-162.

Sun, D., H.S. Courtney, and E.H Beachey. "Berberine sulfate blocks adherence of Streptococcus pyogenes to epithelial cells, fibronectin, and hexadecane." Antimicrob Agents Chemother 32, no. 9 (1988): 1370-4.

ORGANIZATIONS

National Institute of Allergy and Infectious Disease. 31 Center Drive MSC 2520, Building 31, Room 7A-50, Bethesda, MD 20892-2520.

OTHER

Discovery Health. http://www.discoveryhealth.com.

National Institute of Allergy and Infectious Disease. http://www.niaid.nih.gov.

Greg Annussek

Rebecca J. Frey, PhD

STREP THROAT

DEFINITION

Strep throat is an infection of the pharynx (pronounced FAAR-ingks). The pharynx is the part of the throat that connects the mouth and the larynx (pronounced LAAR-ingks), or voice box. Strep throat is caused by a group of bacteria known as the streptococcal (pronounced strep-tuh-KOK-uhl) bacteria. If untreated, a strep throat can lead to serious complications, such as rheumatic fever (see rheumatic fever entry).

DESCRIPTION

Strep throat accounts for 5 to 10 percent of all sore throats. Anyone can get the disease but it is most common among school age children and certain groups of adults. Adults at higher risk include smokers, people who are unusually tired, and those who live in damp, crowded conditions.

Strep throat occurs most often between November and April. The disease passes directly from person to person and coughing, sneezing, or close contact can transfer it from one person to another. If someone in a household has strep throat there is a one in four chance that another person in the household will get the infection, too.

CAUSES

Strep throat is caused by various types of bacteria called Group A streptococcal bacteria. These bacteria cause other common infections also, such as tonsillitis and scarlet fever.

Strep Throat: Words to Know

Antibiotic:

A substance derived from bacteria or other organisms that fights the growth of other bacteria or organisms.

Lactobacillus acidophilus :

A bacterium found in yogurt that changes the balance of bacteria in the intestine in a beneficial way.

Lymph nodes:

Small round or oval bodies within the immune system. Lymph nodes provide materials that fight disease and help remove bacteria and other foreign material from the body.

Throat culture:

A sample of tissue taken from a person's throat for analysis. The culture is often taken by swiping a cotton swab across the back of the throat.

Tonsillitis:

An infection and swelling of the tonsils.

SYMPTOMS

The first symptoms of strep throat appear one to five days after a person is infected. The symptoms are no different from any other kind of sore throat (see sore throat entry). They include fever, chills, headache, muscle aches, nausea, a feeling of tiredness, and swollen lymph glands. (Lymph nodes are small round or oval bodies that are part of the body's immune system.) The patient's tonsils will be swollen and have bright red with white or yellow patches on them. A person with strep throat often has bad breath. Strep throat can often spread and cause an infection to the tonsils (see tonsillitis entry).

Some people with the disease may have few or no symptoms of strep throat. Many young children may get a headache or stomachache, but show no signs of having a sore throat. Other patients develop a high fever along with a sunburn-like rash on the face and upper body, and their tongues may become right red. This form of the infection is known as scarlet fever (see scarlet fever entry). Scarlet fever is no more dangerous than strep throat and both illnesses are treated the same way.

A serious complication of strep throat is rheumatic fever. Rheumatic fever (pronounced roo-MAT-ick FEE-vur) occurs most often in children between the ages of five and fifteen. However, rheumatic fever is relatively rare and is seldom a problem if strep throat is treated properly and quickly.

DIAGNOSIS

The first steps in diagnosing strep throat are a patient history and physical examination. The doctor will ask if the patient has been around other people with the infection. He or she will also examine the patient's throat and chest. The doctor will also try to eliminate other potential causes of the symptoms, such as bronchitis (see bronchitis entry) or sinus infection.

Two kinds of tests are available for strep throat. Both involve taking a throat culture, which is done by using a cotton swab to remove a sample of tissue from the sore area in the throat. The sample can then be used for a rapid strep test or a culture.

The rapid test shows whether streptococcal bacteria are present in the throat. The results are available in about twenty minutes. The advantage of the test is the speed with which a diagnosis can be made. Its disadvantage is its high rate of error. The results are wrong in about 20 percent of all cases.

For this reason, the throat culture is often used for a second test. In this test, the sample obtained from the throat is allowed to grow in a warm, moist place for a period of twenty-four to forty-eight hours. During this period, the bacteria reproduce and grow. They reach a size where they can be studied under a microscope to see what types of bacteria are present. This test produces a much higher rate of accuracy in determining whether a patient has strep throat.

TREATMENT

Strep throat is treated with antibiotics. Antibiotics are substances derived from bacteria or other organisms that fight the growth of other bacteria or organisms. Penicillin is the most common antibiotic used. The penicillin is usually given orally (by mouth). The usual treatment lasts for ten days. Patients are advised to be sure that they take all of the medication given. If they stop too soon, the infection may return. Penicillin is sometimes be given by injection. A long-lasting form of the drug (Bicillin) may have the same effect as a 10-day treatment with pills.

About 10 percent of the time, penicillin is not effective against the strep bacteria. In that case, another antibiotic is prescribed. People who are allergic to penicillin may also require an alternative. Other antibiotics used in such cases include amoxicillin, clindamycin, erythromycin, or cephalosporin.

Though strep throat usually gets better on its own after four or five days, antibiotics are usually prescribed anyway, to prevent complications such as rheumatic fever from developing.

Home Care for Strep Throat

Some simple home care treatments can be used to make a patient with strep throat more comfortable. These treatments are used in addition to, not in place of, antibiotics. These home treatments include:

• Pain killers, such as acetaminophen or ibuprofen. Aspirin should not be given to children because of the risk of Reye's syndrome (see Reye's syndrome entry).
• Gargling with double strength tea or warm salt water
• Drinking plenty of fluids, excepting for acidic fluids such as orange or grapefruit juice
• Eating soft, nutritious foods, such as noodle soup
• Avoiding smoking and second hand smoke
• Resting until the fever is gone and then resuming normal activities gradually
• Using a room humidifier

Most throat lozenges and sprays available in drug stores should be avoided. They are likely to make a strep throat worse.

Alternative Treatment

Most alternative treatments are designed to ease the symptoms of strep throat. They do not help to cure the infection. One recommended treatment is the use of the bacterium that occurs in yogurt, Lactobacillus acidophilus, (pronounced LACK-toe-buh-SILL-us as-ih-DOFE-uh-luhss) to counteract the effects of antibiotics on bacteria that occur naturally in the intestines.

Other suggested treatments include:

• Inhaling the fragrances of certain herbs, such as lavender, thyme, eucalyptus, sage, and sandalwood
• Gargling with a mixture of water, salt, and tumeric, alum, sumac, sage, or bayberry
• Taking a tea made from osha root, sage, Echinacea, or cleavers

PROGNOSIS

Patients with strep throat usually begin feeling better about twenty-four hours after first taking antibiotics. Symptoms rarely last longer than five days.

People remain contagious until they have been taking antibiotics for twenty-four hours. Children should not return to school until they are no longer contagious. Food handlers should not work during the same time period. People who are not treated with antibiotics may continue to spread strep bacteria for several months.

PREVENTION

The risk of passing strep throat from one person to another can be reduced by some simple actions, such as:

• Washing hands frequently and well, especially after nose blowing or sneezing and before handling foods
• Disposing of used tissues properly

• Avoiding close contact with someone who has strep throat
• Not sharing food and eating utensils with other people
• Not smoking

FOR MORE INFORMATION

Web sites

"Ask NOAH About: Respiratory Disorders." NOAH: New York Online Access to Health. [Online] http://www.noah.cuny.edu/respiratory/resp.html#STREP (accessed on October 31, 1999).

National Institute of Allergy and Infectious Diseases. "A Group of Streptococcal Infection." NIAID Fact Sheet. [Online] http://www.niaid.nih.govfactsheets/strep.htm (accessed on February 1, 1999).