Group A streptococcal infections are caused by group A streptococcus, a bacteria that causes a variety of health problems, including strep throat, impetigo, cellulitis, erysipelas, and scarlet fever. There are more than 10 million group A strep infections each year.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Group A streptococci (GAS) are defined gram-positive coccal-shaped bacteria that produce beta-hemolysis (lysis
of red blood cells producing clear or transparent areas in special growth media)
and appear usually as a chain of two or more bacteria and have molecules on their surface known as Lancefield group A antigens.
Streptococcus (GAS) organisms are usually spread by direct human-to-human
transfer. Occasionally, they can be spread by droplets or by a person touching
items recently handled by an infected individual (also termed fomites).
Early signs and symptoms of necrotizing fasciitis include
fever, severe pain and swelling, and erythema (redness) at the wound site or
site where GAS organisms entered the body; later signs and symptoms include
fluid discharge from the infected tissue, skin loss, and low blood pressure
Early symptoms of toxic shock syndrome are nonspecific, often begin with
flu-like symptoms of mild fever and malaise, then the condition often suddenly advances with
symptoms of high fever, nausea, vomiting, diarrhea, skin rash, and a low blood
pressure with possible progression to include confusion,
skin loss from the palms of the hands and from the soles of the feet.
of GAS is made by culturing the bacteria and having the laboratory identify the
bacteria by metabolic functions and immunologic tests; rapid tests are based on
immunological recognition of GAS antigens taken from the patient by swabbing the
Although oral antibiotics (many types) are effective in treating milder
forms of GAS infections, more serious forms of GAS such as invasive GAS disease
usually require multiple antibiotics administered IV; in addition, some patients
may require surgery to remove dead and dying tissue.
The prognosis (outcome) of
GAS infections, especially mild infections, is usually good to excellent.
However, as the disease progresses from moderate to severe, the prognosis
decreases from good to poor; early effective treatment may improve the prognosis.
Prevention of GAS infections is possible by attention to good hygiene such as
hand washing and avoiding eating or drinking from the same containers used by
other people and avoiding direct and indirect (for example, droplet or particle
contamination of clothing) contact with a infected individual; early treatment
of GAS infections can reduce or avoid the progression to more severe disease.
Although research is ongoing, there is no commercially available vaccine to
prevent GAS infections.
Reviewed by Mary D. Nettleman, MD, MS, MACP on 5/9/2012
Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: Jay W. Marks, MD, William C. Shiel Jr., MD, FACP, FACR
Media reports have popularized the term "flesh-eating
bacteria" to refer to a very rare but serious bacterial infection known as
necrotizing fasciitis. Necrotizing fasciitis is an infection that starts in the
tissues just below the skin and spreads along the flat layers of tissue (known
as fascia) that separate different layers of soft tissue, such as muscle and
fat. This dangerous infection is most common in the arms, legs, and abdominal
wall and is fatal in
30%-40% of cases.
Although necrotizing fasciitis may be caused by an
infection with one or more than one bacterium, in most cases the term
flesh-eating bacteria has been
applied to describe infections caused by the bacterium known as Streptococcus
pyogenes. The term flesh-eating has been used because the bacterial infection
produces toxins that destroy tissues such as muscles, skin, and fat.
Streptococcus pyogenes is a member of the group A streptococci, a group of bacteria that are responsible
for mild cases of sore throat(pharyngitis) and
skin infections, as well as rare, severe illnesses such as toxic shock syndromeand necrotizing fasciitis. Most infections with group A streptococci result in
mild illness and may not even produce symptoms.
Almost 75 million dogs live in the United States, and since many victims of
dog bites don't seek medical care or report the attack, it may be that the U.S.
Center for Disease Control and Prevention (CDC)'s "...