Types of Group A Streptococcal Infections

Cellulitis and Erysipelas

Cellulitis is inflammation of the skin and deep underlying tissues. Erysipelas is an inflammatory disease of the upper layers of the skin. Group A strep (streptococcal) bacteria are the most common cause of cellulitis and erysipelas. To learn more visit the Medline Plus cellulitis site or visit the MedlinePlus erysipelas site.


Impetigo is an infection of the top layers of the skin and is most common among children ages 2 to 6 years. It usually starts when bacteria get into a cut, scratch, or insect bite. To learn more visit the MedlinePlus impetigo site.

Scarlet Fever

Scarlet fever – or scarlatina – is a bacterial infection caused by group A Streptococcus or "group A strep." This illness affects a small percentage of people who have strep throat or, less commonly, streptococcal skin infections. To learn more visit the MedlinePlus scarlet fever site.

Severe Strep Infections

Some types of group A strep bacteria cause severe infections, such as

Strep Throat

Many things can cause that unpleasant, scratchy, and sometimes painful condition known as a sore throat. Viruses, bacteria, allergens, environmental irritants (such as cigarette smoke), chronic postnasal drip, and fungi can all cause a sore throat. While many sore throats will get better without treatment, some throat infections—including strep throat—may need antibiotic treatment.  To learn more visit the MedlinePlus strep throat site.

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