Streptococcus pyogenes
Overview
 
Streptococcus pyogenes is a spherical
Coccus
Coccus can be used to describe any bacterium that has a spherical shape. It is one of the three distinct types of bacteria shapes, the other two being bacillus and spirillum cells...

, Gram-positive
Gram-positive
Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...

 bacterium that is the cause of group A streptococcal infection
Group A streptococcal infection
The group A streptococcus bacterium is a form of β-hemolytic Streptococcus bacteria responsible for most cases of streptococcal illness. Other types may also cause infection...

s. S. pyogenes displays streptococcal group A antigen
Antigen
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...

 on its cell wall
Cell wall
The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, and also acts as a filtering mechanism. A major function of the cell wall is to...

. S. pyogenes typically produces large zones of beta-hemolysis
Hemolysis (microbiology)
Hemolysis is the breakdown of red blood cells. The ability of bacterial colonies to induce hemolysis when grown on blood agar is used to classify certain microorganisms. This is particularly useful in classifying streptococcal species...

 (the complete disruption of erythrocytes and the release of hemoglobin
Hemoglobin
Hemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of all vertebrates, with the exception of the fish family Channichthyidae, as well as the tissues of some invertebrates...

) when cultured on blood agar plate
Agar plate
An agar plate is a Petri dish that contains a growth medium used to culture microorganisms or small plants like the moss Physcomitrella patens.Selective growth compounds may also be added to the media, such as antibiotics....

s, and are therefore also called Group A (beta-hemolytic) Streptococcus
Streptococcus
Streptococcus is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. Cellular division occurs along a single axis in these bacteria, and thus they grow in chains or pairs, hence the name — from Greek στρεπτος streptos, meaning...

(abbreviated GABHS).

Streptococci are catalase
Catalase
Catalase is a common enzyme found in nearly all living organisms that are exposed to oxygen, where it catalyzes the decomposition of hydrogen peroxide to water and oxygen...

-negative.
Encyclopedia
Streptococcus pyogenes is a spherical
Coccus
Coccus can be used to describe any bacterium that has a spherical shape. It is one of the three distinct types of bacteria shapes, the other two being bacillus and spirillum cells...

, Gram-positive
Gram-positive
Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...

 bacterium that is the cause of group A streptococcal infection
Group A streptococcal infection
The group A streptococcus bacterium is a form of β-hemolytic Streptococcus bacteria responsible for most cases of streptococcal illness. Other types may also cause infection...

s. S. pyogenes displays streptococcal group A antigen
Antigen
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...

 on its cell wall
Cell wall
The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, and also acts as a filtering mechanism. A major function of the cell wall is to...

. S. pyogenes typically produces large zones of beta-hemolysis
Hemolysis (microbiology)
Hemolysis is the breakdown of red blood cells. The ability of bacterial colonies to induce hemolysis when grown on blood agar is used to classify certain microorganisms. This is particularly useful in classifying streptococcal species...

 (the complete disruption of erythrocytes and the release of hemoglobin
Hemoglobin
Hemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of all vertebrates, with the exception of the fish family Channichthyidae, as well as the tissues of some invertebrates...

) when cultured on blood agar plate
Agar plate
An agar plate is a Petri dish that contains a growth medium used to culture microorganisms or small plants like the moss Physcomitrella patens.Selective growth compounds may also be added to the media, such as antibiotics....

s, and are therefore also called Group A (beta-hemolytic) Streptococcus
Streptococcus
Streptococcus is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. Cellular division occurs along a single axis in these bacteria, and thus they grow in chains or pairs, hence the name — from Greek στρεπτος streptos, meaning...

(abbreviated GABHS).

Streptococci are catalase
Catalase
Catalase is a common enzyme found in nearly all living organisms that are exposed to oxygen, where it catalyzes the decomposition of hydrogen peroxide to water and oxygen...

-negative. In ideal conditions, S. pyogenes has an incubation period of approximately 1–3 days. It is an infrequent, but usually pathogenic, part of the skin flora
Skin flora
The skin flora are the microorganisms which reside on the skin. Most research has been upon those that reside upon the 2 square metres of human skin. Many of them are bacteria of which there are around 1000 species upon human skin from 19 phyla. The total number of bacteria on an average human has...

.

It is estimated that there are more than 700 million infections each year and over 650,000 cases of severe, invasive infections which have a mortality rate of 25 %.

Serotyping

In 1928, Rebecca Lancefield
Rebecca Lancefield
Rebecca Craighill Lancefield was a prominent American microbiologist. She joined the Rockefeller Institute for Medical Research in New York in 1918, and was associated with that institute throughout her long and outstanding career. Her bibliography comprises more than 50 publications published...

 published a method for serotyping S. pyogenes based on its M protein
M protein (Streptococcus)
M protein is a virulence factor that can be produced by certain species of Streptococcus.Viruses, parasites and bacteria are covered in protein and sugar molecules that help them gain entry into a host by counteracting the host's defences. One such molecule is the M protein produced by certain...

, a virulence
Virulence
Virulence is by MeSH definition the degree of pathogenicity within a group or species of parasites as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenicity of an organism - its ability to cause disease - is determined by its...

 factor displayed on its surface. Later in 1946, Lancefield described the serologic classification of S. pyogenes isolates based on their surface T antigen. Four of the 20 T antigens have been revealed to be pili
Pilus
right|thumb|350px|Schematic drawing of bacterial conjugation. 1- Donor cell produces pilus. 2- Pilus attaches to recipient cell, brings the two cells together. 3- The mobile plasmid is nicked and a single strand of DNA is then transferred to the recipient cell...

, which are used by bacteria to attach to host cells. Over 100 M serotypes and approximately 20 T serotypes are known. The disease was widely publicized in the early 90's as it was the cause of death of Jim Henson
Jim Henson
James Maury "Jim" Henson was an American puppeteer best known as the creator of The Muppets. As a puppeteer, Henson performed in various television programs, such as Sesame Street and The Muppet Show, films such as The Muppet Movie and The Great Muppet Caper, and created advanced puppets for...

.

Pathogenesis

S. pyogenes is the cause of many important human diseases, ranging from mild superficial skin infections to life-threatening systemic diseases. Infections typically begin in the throat or skin. Examples of mild S. pyogenes infections include pharyngitis
Pharyngitis
Pharyngitis is an inflammation of the throat or pharynx. In most cases it is quite painful, and is the most common cause of a sore throat.Like many types of inflammation, pharyngitis can be acute – characterized by a rapid onset and typically a relatively short course – or chronic....

 ("strep throat") and localized skin infection ("impetigo
Impetigo
Impetigo is a highly contagious bacterial skin infection most common among pre-school children. People who play close contact sports such as rugby, American football and wrestling are also susceptible, regardless of age. Impetigo is not as common in adults. The name derives from the Latin impetere...

"). Erysipelas
Erysipelas
Erysipelas is an acute streptococcus bacterial infection of the deep epidermis with lymphatic spread.-Risk factors:...

 and cellulitis
Cellulitis
Cellulitis is a diffuse inflammation of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin. Cellulitis can be caused by normal skin flora or by exogenous bacteria, and often occurs where the skin has previously been broken: cracks in the skin, cuts, blisters,...

 are characterized by multiplication and lateral spread of S. pyogenes in deep layers of the skin. S. pyogenes invasion and multiplication in the fascia
Fascia
A fascia is a layer of fibrous tissue that permeates the human body. A fascia is a connective tissue that surrounds muscles, groups of muscles, blood vessels, and nerves, binding those structures together in much the same manner as plastic wrap can be used to hold the contents of sandwiches...

 can lead to necrotizing fasciitis
Necrotizing fasciitis
Necrotizing fasciitis , commonly known as flesh-eating disease or Flesh-eating bacteria syndrome, is a rare infection of the deeper layers of skin and subcutaneous tissues, easily spreading across the fascial plane within the subcutaneous tissue.Necrotizing fasciitis is a quickly progressing and...

, a potentially life-threatening condition requiring surgical treatment.

Infections due to certain strains of S. pyogenes can be associated with the release of bacterial toxin
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...

s. Throat infections associated with release of certain toxins lead to scarlet fever
Scarlet fever
Scarlet fever is a disease caused by exotoxin released by Streptococcus pyogenes. Once a major cause of death, it is now effectively treated with antibiotics...

. Other toxigenic S. pyogenes infections may lead to streptococcal toxic shock syndrome
Toxic shock syndrome
Toxic shock syndrome is a potentially fatal illness caused by a bacterial toxin. Different bacterial toxins may cause toxic shock syndrome, depending on the situation. The causative bacteria include Staphylococcus aureus and Streptococcus pyogenes...

, which can be life-threatening.

S. pyogenes can also cause disease in the form of postinfectious "nonpyogenic" (not associated with local bacterial multiplication and pus formation) syndromes. These autoimmune-mediated complications follow a small percentage of infections and include rheumatic fever
Rheumatic fever
Rheumatic fever is an inflammatory disease that occurs following a Streptococcus pyogenes infection, such as strep throat or scarlet fever. Believed to be caused by antibody cross-reactivity that can involve the heart, joints, skin, and brain, the illness typically develops two to three weeks after...

 and acute postinfectious glomerulonephritis
Glomerulonephritis
Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys...

. Both conditions appear several weeks following the initial streptococcal infection. Rheumatic fever
Rheumatic fever
Rheumatic fever is an inflammatory disease that occurs following a Streptococcus pyogenes infection, such as strep throat or scarlet fever. Believed to be caused by antibody cross-reactivity that can involve the heart, joints, skin, and brain, the illness typically develops two to three weeks after...

 is characterised by inflammation of the joints and/or heart following an episode of streptococcal pharyngitis
Pharyngitis
Pharyngitis is an inflammation of the throat or pharynx. In most cases it is quite painful, and is the most common cause of a sore throat.Like many types of inflammation, pharyngitis can be acute – characterized by a rapid onset and typically a relatively short course – or chronic....

. Acute glomerulonephritis
Glomerulonephritis
Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys...

, inflammation of the renal
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...

 glomerulus
Glomerulus
A glomerulus is a capillary tuft that is involved in the first step of filtering blood to form urine.A glomerulus is surrounded by Bowman's capsule, the beginning component of nephrons in the vertebrate kidney. A glomerulus receives its blood supply from an afferent arteriole of the renal...

, can follow streptococcal pharyngitis
Pharyngitis
Pharyngitis is an inflammation of the throat or pharynx. In most cases it is quite painful, and is the most common cause of a sore throat.Like many types of inflammation, pharyngitis can be acute – characterized by a rapid onset and typically a relatively short course – or chronic....

 or skin infection.

This bacterium remains acutely sensitive to penicillin
Penicillin
Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

. Failure of treatment with penicillin
Penicillin
Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

 is generally attributed to other local commensal organisms producing β-lactamase, or failure to achieve adequate tissue levels in the pharynx. Certain strains have developed resistance to macrolides, tetracyclines and clindamycin
Clindamycin
Clindamycin rINN is a lincosamide antibiotic. It is usually used to treat infections with anaerobic bacteria but can also be used to treat some protozoal diseases, such as malaria...

.

Virulence factors

S. pyogenes has several virulence
Virulence
Virulence is by MeSH definition the degree of pathogenicity within a group or species of parasites as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenicity of an organism - its ability to cause disease - is determined by its...

 factors that enable it to attach to host tissues, evade the immune response, and spread by penetrating host tissue layers. A carbohydrate-based bacterial capsule composed of hyaluronic acid surrounds the bacterium, protecting it from phagocytosis by neutrophils. In addition, the capsule and several factors embedded in the cell wall, including M protein
M protein (Streptococcus)
M protein is a virulence factor that can be produced by certain species of Streptococcus.Viruses, parasites and bacteria are covered in protein and sugar molecules that help them gain entry into a host by counteracting the host's defences. One such molecule is the M protein produced by certain...

, lipoteichoic acid
Lipoteichoic acid
Lipoteichoic acid is a major constituent of the cell wall of Gram-positive bacteria. These organisms have an inner membrane and, external to it, a thick peptidoglycan layer. It consists of teichoic acids, long chains of ribitol phosphate and is anchored to the lipid bilayer via a glyceride...

, and protein F (SfbI) facilitate attachment to various host cells. M protein also inhibits opsonization by the alternative complement pathway
Complement system
The complement system helps or “complements” the ability of antibodies and phagocytic cells to clear pathogens from an organism. It is part of the immune system called the innate immune system that is not adaptable and does not change over the course of an individual's lifetime...

 by binding to host complement regulators. The M protein found on some serotypes is also able to prevent opsonization by binding to fibrinogen
Fibrinogen
Fibrinogen is a soluble plasma glycoprotein, synthesised by the liver, that is converted by thrombin into fibrin during blood coagulation. This is achieved through processes in the coagulation cascade that activate the zymogen prothrombin to the serine protease thrombin, which is responsible for...

. However, the M protein is also the weakest point in this pathogen's defense, as antibodies
Antibody
An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...

 produced by the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

 against M protein target the bacteria for engulfment by phagocytes. M proteins are unique to each strain, and identification can be used clinically to confirm the strain causing an infection.

S. pyogenes releases a number of proteins, including several virulence factors, into its host:
Name Description
Streptolysin O An exotoxin
Exotoxin
An exotoxin is a toxin excreted by a microorganism, like bacteria, fungi, algae, and protozoa. An exotoxin can cause damage to the host by destroying cells or disrupting normal cellular metabolism. They are highly potent and can cause major damage to the host...

 that is one of the bases of the organism's beta-hemolytic property.
Streptolysin S A cardiotoxic exotoxin that is another beta-hemolytic component. Streptolysin S is not immunogenic and O2 stable. A potent cell poison affecting many types of cell including neutrophils, platelets, and sub-cellular organelles, streptolysin S causes an immune response and detection of antibodies to it; antistreptolysin O (ASO) can be clinically used to confirm a recent infection.
Streptococcal pyogenic exotoxin A (SpeA) Superantigen
Superantigen
Superantigens are a class of antigens which cause non-specific activation of T-cells resulting in oligoclonal T cell activation and massive cytokine release...

s secreted by many strains of S. pyogenes. This pyrogenic exotoxin is responsible for the rash
Rash
A rash is a change of the skin which affects its color, appearance or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracked or blistered, swell and may be painful. The causes, and...

 of scarlet fever
Scarlet fever
Scarlet fever is a disease caused by exotoxin released by Streptococcus pyogenes. Once a major cause of death, it is now effectively treated with antibiotics...

 and many of the symptoms of streptococcal toxic shock syndrome
Toxic shock syndrome
Toxic shock syndrome is a potentially fatal illness caused by a bacterial toxin. Different bacterial toxins may cause toxic shock syndrome, depending on the situation. The causative bacteria include Staphylococcus aureus and Streptococcus pyogenes...

.
Streptococcal pyogenic exotoxin C (SpeC)
Streptokinase
Streptokinase
Streptokinase , a protein secreted by several species of streptococci can bind and activate human plasminogen. SK is used as an effective and inexpensive thrombolysis medication in some cases of myocardial infarction and pulmonary embolism...

Enzymatically activates plasminogen, a proteolytic enzyme, into plasmin
Plasmin
Plasmin is an important enzyme present in blood that degrades many blood plasma proteins, most notably, fibrin clots. The degradation of fibrin is termed fibrinolysis. In humans, the plasmin protein is encoded by the PLG gene.- Function :...

, which in turn digests fibrin
Fibrin
Fibrin is a fibrous, non-globular protein involved in the clotting of blood. It is a fibrillar protein that is polymerised to form a "mesh" that forms a hemostatic plug or clot over a wound site....

 and other proteins.
Hyaluronidase
Hyaluronidase
The hyaluronidases are a family of enzymes that degrade hyaluronic acid.In humans, there are six associated genes, including HYAL1, HYAL2, HYAL3, and PH-20/SPAM1.-Use as a drug:...

It is widely assumed hyaluronidase
Hyaluronidase
The hyaluronidases are a family of enzymes that degrade hyaluronic acid.In humans, there are six associated genes, including HYAL1, HYAL2, HYAL3, and PH-20/SPAM1.-Use as a drug:...

 facilitates the spread of the bacteria through tissues by breaking down hyaluronic acid, an important component of connective tissue
Connective tissue
"Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...

. However, very few isolates of S. pyogenes are capable of secreting active hyaluronidase due to mutations in the gene that encode the enzyme. Moreover, the few isolates that are capable of secreting hyaluronidase do not appear to need it to spread through tissues or to cause skin lesions. Thus, the true role of hyaluronidase in pathogenesis, if any, remains unknown.
Streptodornase Most strains of S. pyogenes secrete up to four different DNases, which are sometimes called streptodornase. The DNases protect the bacteria from being trapped in neutrophil extracellular traps
Neutrophil extracellular traps
Neutrophil extracellular traps are networks of extracellular fibers, primarily composed of DNA from neutrophils, which bind pathogens....

 (NETs) by digesting the NET's web of DNA, to which are bound neutrophil serine protease
Serine protease
Serine proteases are enzymes that cleave peptide bonds in proteins, in which serine serves as the nucleophilic amino acid at the active site.They are found ubiquitously in both eukaryotes and prokaryotes...

s that can kill the bacteria.
C5a
C5a
C5a is a protein fragment released from complement component C5. In humans, the polypeptide contains 74 amino acids. NMR spectroscopy proved that the molecule is composed of four helices and loops connecting the helices. On the N terminus a short 1.5 turn helix is also present. The longest helix...

 peptidase
C5a peptidase cleaves a potent neutrophil chemotaxin called C5a
C5a
C5a is a protein fragment released from complement component C5. In humans, the polypeptide contains 74 amino acids. NMR spectroscopy proved that the molecule is composed of four helices and loops connecting the helices. On the N terminus a short 1.5 turn helix is also present. The longest helix...

, which is produced by the complement system
Complement system
The complement system helps or “complements” the ability of antibodies and phagocytic cells to clear pathogens from an organism. It is part of the immune system called the innate immune system that is not adaptable and does not change over the course of an individual's lifetime...

. C5a peptidase is necessary to minimize the influx of neutrophils early in infection as the bacteria are attempting to colonize the host's tissue.
Streptococcal chemokine protease The affected tissue of patients with severe cases of necrotizing fasciitis
Necrotizing fasciitis
Necrotizing fasciitis , commonly known as flesh-eating disease or Flesh-eating bacteria syndrome, is a rare infection of the deeper layers of skin and subcutaneous tissues, easily spreading across the fascial plane within the subcutaneous tissue.Necrotizing fasciitis is a quickly progressing and...

 are devoid of neutrophils. The serine protease
Serine protease
Serine proteases are enzymes that cleave peptide bonds in proteins, in which serine serves as the nucleophilic amino acid at the active site.They are found ubiquitously in both eukaryotes and prokaryotes...

 ScpC, which is released by S. pyogenes, is responsible for preventing the migration of neutrophils to the spreading infection. ScpC degrades the chemokine
Chemokine
Chemokines are a family of small cytokines, or proteins secreted by cells. Their name is derived from their ability to induce directed chemotaxis in nearby responsive cells; they are chemotactic cytokines...

 IL-8
Interleukin 8
Interleukin-8 is a chemokine produced by macrophages and other cell types such as epithelial cells. It is also synthesized by endothelial cells, which store IL-8 in their storage vesicles, the Weibel-Palade bodies...

, which would otherwise attract neutrophils to the site of infection. C5a peptidase, although required to degrade the neutrophil chemotaxin C5a in the early stages of infection, is not required for S. pyogenes to prevent the influx of neutrophils as the bacteria spread through the fascia
Fascia
A fascia is a layer of fibrous tissue that permeates the human body. A fascia is a connective tissue that surrounds muscles, groups of muscles, blood vessels, and nerves, binding those structures together in much the same manner as plastic wrap can be used to hold the contents of sandwiches...

.

Diagnosis

Usually, a throat swab is taken to the laboratory for testing. A Gram stain is performed to show Gram-positive cocci in chains. Then, the organism is cultured on blood agar with an added bacitracin
Bacitracin
Bacitracin is a mixture of related cyclic polypeptides produced by organisms of the licheniformis group of Bacillus subtilis var Tracy, isolation of which was first reported in 1945....

 antibiotic disk to show beta-hemolytic
Hemolysis (microbiology)
Hemolysis is the breakdown of red blood cells. The ability of bacterial colonies to induce hemolysis when grown on blood agar is used to classify certain microorganisms. This is particularly useful in classifying streptococcal species...

 colonies and sensitivity (zone of inhibition around the disk) for the antibiotic. Culture on non-blood containing agar then, perform catalase
Catalase
Catalase is a common enzyme found in nearly all living organisms that are exposed to oxygen, where it catalyzes the decomposition of hydrogen peroxide to water and oxygen...

 test, which should show a negative reaction for all Streptococci. S. pyogenes is CAMP (not to be confused with cAMP) and hippurate tests negative. Serological identification of the organism involves testing for the presence of group A specific polysaccharide in the bacterium's cell wall using the Phadebact test.

Treatment

The treatment of choice is penicillin
Penicillin
Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

 and the duration of treatment is well established as being 10 days minimum. There has been no reported instance of penicillin-resistance to date, although since 1985, there have been many reports of penicillin-tolerance.

Macrolides, chloramphenicol
Chloramphenicol
Chloramphenicol is a bacteriostatic antimicrobial that became available in 1949. It is considered a prototypical broad-spectrum antibiotic, alongside the tetracyclines, and as it is both cheap and easy to manufacture it is frequently found as a drug of choice in the third world.Chloramphenicol is...

 and tetracyclines may be used if the strain isolated has been shown to be sensitive, but resistance is much more common.

Prevention

No vaccines are currently available to protect against S. pyogenes infection, but specific protective antibody has been shown to persist as long as 45 years after the original infection.

Literature

  • Rosenbach. Mikro-Organismen bei den Wund-Infections-Krankheiten des Menschen. http://www.archive.org/details/mikroorganismenb00roseuoft
    • (corresponding summary article)
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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