Group A Streptococcus (GAS) Essay

What are these other serious illnesses that are caused by group A Streptococcus? What is group A Streptococcus? Group A streptococci are bacteria commonly found in the throat and on the skin. The vast majority of GAS infections are relatively mild illnesses, such as strep throat and impetigo. Occasionally, however, these bacteria can cause much more severe and even life threatening diseases such as necrotizing fasciitis (occasionally described as "the flesh-eating bacteria") and streptococcal toxic shock syndrome (STSS). In addition, people may carry group A streptococci in the throat or on the skin and have no symptoms of disease.

Group B Streptococcus agalactiae is an important Gram-positive bacterial pathogen that cause a wide variety of clinical infections, ranging from septicemia to meningitis. The reported lethality of severe S. agalactiae infections is ranging from 4 to 6% in the United States. Of note, it has been suggested that the incidence of neonatal disease is considerably greater than reported, because the requirement for positive cultures from blood or cerebrospinal fluid may underestimates the true burden of disease. Therefore, in this review I focused on virulence factors of S. agalactiae in order to elucidate aspects of the infection.

Streptococcus Pyogenes is a very diverse bacteria with effects ranging from nothing or a mild sore throat, to flesh eating disease, causing death in 40-60% of patients. The major and most common illnesses associated with this bacteria

A wound became anaerobic because there is blood supply interruption this is a condition called ischemia. After ischemia tissue dye and that condition is called necrosis after this dead tissue produce no more blood supply and this can be a lethal condition called Gas Gangrene.

It is not unusual for some healthy women to harbor Group B streptococcus bacteria in their rectum and vagina. These microorganisms do not usually cause disease when few in number, but when they grow in number and colonize these areas, bacterial infection can become severe.

“Streptococcus is a bacteria that infects the Immune System. The Immune System is made up of a network of cells, tissues, and organs that all work together to protect the body”("Immune Response"). According

S.pyogenes is a species of bacteria that usually attack children 6-18 years old . S.pyogenes is also known as strep throat which is a really common infection.S.pyogenes is an infection in the throat and tonsils. No one can diagnose throat just by looking at your throat. Whenever you have the symptoms you should go the doctors so they can give a “rapid strep test” which involves swabbing your throat. If you test positive for strep throat the doctor will give you some antibiotics which will help you get well by decreasing the time you’re sick ,weakening the symptoms, stops its infectivity and it also prevents more serious complications such as tonsil and sinus infections and rheumatic fever.

Before the turn of the 21st century, physicians across the country were realizing that the possibility of being able to treat and cure virtually any microbial infection with the use of a single or a combination of antimicrobial medications was becoming more and more of a challenge. In the late 1960s and early 1970s, reports of pathogenic resistance to even the most potent antimicrobial medications of the time were being sent to the Centers for Disease Control. Among even the most dangerous pathogens that have developed and are developing drug resistance to one or many antimicrobials, Staphylococcus aureus (S. aureus) is perhaps a case in which the world is most familiar and of the greatest concern within the medical community due to its natural virulence-its ability to cause a multitude of life-threatening infections, and its above average ability to combat and adapt to a vast array of environmental conditions.

GAS is associated with many other common illnesses, such as pharyngitis, and scarlet fever (2). It is also a gram-positive bacterium, meaning the bacterium itself has a thick cell wall made of the protein peptidoglycan. This extra protein layer makes it more susceptible to antibiotics. While this susceptibility aids in treatment once necrotizing fasciitis is diagnosed, these bacteria are carried every day by humans in our noses, throats, and skin, showing no physical symptoms. Once an object pierces the body, infection is more likely because this bacterium is so widely prevalent. When GAS causes necrotizing fasciitis, it can also occur simultaneously with Streptococcal Toxic Shock Syndrome (STSS). This additional, and sometimes fatal condition STTS, accelerates the metastasis of necrotizing fasciitis (1).

Streptococcal Pharyngitis is an upper respiratory infection caused by group A streptococci (GAS). This gram-positive bacterial group consists solely of Streptococcus pyrogens, the same bacterium responsible for many skin and soft tissue infections, such as impetigo, erysipelas, and acute bacterial endocarditis (Tortora, Funke & Case, 2013). Symptoms include sore throat, fever, Swollen, tender lymph nodes in the neck and inflammation of the middle ear. There are multiple ways of diagnosing Strep throat. Streptococcal Pharyngitis is most commonly diagnosed using enzyme immunoassay (EIA); which are hypersensitive and straightforward. Another way for diagnosing is using a sterile swab then rubbing it over the back of the throat and tonsils to

Osteomyelitis is a broad and debilitating disease typically triggered by a variety of conditions. Osteomyelitis starts off as inflammation seen within bone and bone marrow that can quickly progress into a large, subclassified infection. The length of time the infection has been present in the body and whether or not there is a pus formation or increased density among the infected bone is commonly used to classify severity. Pyrogenic bacteria or mycobacteria systematically attack the route and anatomic location of the infection evolving acute conditions into chronic ones. “Staphylococcus Aureus is a gram-positive, round shaped, non-mobile cocci typically found in clusters inside these wounds. Staphylococcus Aureus is one of the most common causes of infections after injury or surgery and affects nearly 500,000 patients in hospitals each year. Staphylococcus Aureus belongs to the family Staphylcoccaceae and survives by affecting all known mammalian species including humans” (www.news-medical.net). Osteomyelitis can start in one area of the body while spreading through the blood stream into other bone regions. Typical treatment options for Osteomyelitis includes antibiotics, removal of

Streptococcus pyogenes is a very common bacteria found in humans. It is very transmissible and can be caught through the air via coughing or sneezing. This form of Strep. illness is referred to as Streptococcal pharyngitis, also known as Strep. throat, which can complicate into Scarlet Fever. It is also possible to be infected through abrasions of the skin, which can result in cellulitis, impetigo, or even necrotizing fasciitis. Aside from human to human contact, these bacteria can also be found in unpasteurized milk. There is no vaccine for Streptococcal infections, though antibiotics such as penicillin still work very well against them.

It begins with a harmless cut in the skin and spreads rapidly into nearby tissue. When streptococci on the skin are introduced to the cut, strains of group A release enzymes and toxins that greatly increase invasiveness and virulence. Invasive bacteria are pathogens that can invade parts of the body where bacteria are not normally present, such as the bloodstream, and soft tissues like muscle or fat. Virulence is the degree of pathogenicity determined by its ability to establish itself in a host and survive the host defense. Virulence factors of group A streptococci include (1) M protein and lipoteichoic acid for attachment; (2) a hyaluronic acid capsule that inhibits phagocytosis; (3) other extracellular products, such as pyrogenic (erythrogenic) toxin, which causes the rash of scarlet fever; and (4) streptokinase, streptodornase (DNase B), and streptolysins. Some strains are nephritogenic. Immune-mediated sequelae do not reflect dissemination of bacteria. Nongroup A strains have no defined virulence factors. Antibody to M protein gives type-specific immunity to group A streptococci. Antibody to erythrogenic toxin prevents the rash of scarlet fever. Immune mechanisms are important in the pathogenesis of acute rheumatic fever. S. pyogenes produce several virulence factors that lend to its pathogenicity, or disease-causing capabilities. It contains a capsule that helps allow the bacteria to disguise it from getting engulfed by white blood cells (phagocytosis). It also contains proteins on its cell wall that allows it to adhere to epithelial cells, which allows it to produce disease. S. pyogenes also produces several enzymes that give the bacteria the ability to destroy tissue and spread. The enzymes digest the connective tissue in the skin. Lastly, it produces a wide variety of toxins that can produce

A gram stain is performed from the sputum of the infected patient. The presence of neutrophils and greater than ten gram-positive diplococci usually results in the diagnosis of Streptococcus pneumoniae. For further conformation of this organism, it is streaked on blood agar. When on blood agar the organism should

Virulence Factors: The most important virulence factor of S. aureus is the specific surface proteins that allow the organism to attach to host proteins. The surface proteins of this bacterium allow it to attach to host proteins such as laminin and fibronectin, which form the extracellular matrix of epithelial and endothelial cells. S. aureus also produces a number of membrane damaging toxins that allow the organism to further invade and harm the host, of which the alpha- toxin is the most well studied and is the protein responsible for septic shock. The alpha- toxin is a protein that binds to a specific receptor in platelets and monocytes in humans, forming pores that eventually destroy the cell.