Scarlet Fever

This has been in the news recently so... what is it anyway?


Scarlet fever is an illness caused by a bacteria called Streptococcus pyogenes, or Group A beta-hemolytic Streptococci.  This is the same organism that causes 'strep throat', a bacterial type of pharyngitis (inflammation of the pharynx or throat).

In fact, the illness usually starts with similar symptoms including:
- fever of 38.3 Celsius (101 Fahrenheit) and above
- sore throat, with swollen tonsils covered by white or yellow spots of pus
- difficulty or pain on swallowing
- enlarged, tender lymph nodes in the neck
- chills, headache, nausea, vomiting, stomach pain

The difference is: scarlet fever is accompanied by a rash caused by a toxin the organism produces.  This characteristic rash is what gives scarlet fever its name.

The rash begins over the neck and upper body, and quickly spreads up to the arms and legs, usually within 24 hours.  It is made up of tiny bumps giving it the texture of gooseflesh or coarse sandpaper.  It is red, but blanches or turns pale on pressure.  The redness is more intense in the deep creases or folds of the skin in the neck, armpits, elbows, groin, and knees, forming red lines or streaks.  The face (forehead and cheeks) is also red and flushed, but the area around the mouth remains pale (circumoral pallor).

The tongue also has a characteristic appearance.  At first, it is covered with a white coat (and so is called white strawberry tongue), which is shed after several days leaving a red, bumpy-looking tongue (called red strawberry tongue or raspberry tongue).

Afterwards, the rash fades and the skin begins to peel, and this peeling may take from days to weeks.


Scarlet fever is most common in children of ages 5 to 15 years.  It is usually spread by droplets expelled from an infected person when he/she coughs or sneezes.  So it is good advice to cover the mouth and nose whenever coughing or sneezing, as well as avoiding sharing eating utensils, drinking glasses, and food.
From the time of exposure, it can take up to seven days to the appearance of symptoms.

To diagnose, the doctor will take a swab from the back of the throat and submit it to the laboratory for culture, to see if the bacteria will grow from it.  When this is confirmed, the doctor will prescribe a course of antibiotics.  Note that it is important to complete the course of antibiotics because if not, the bacteria may not be completely removed and develop into drug-resistant strains, and also increase the risk of complications.