Information About Fifth Disease

Fifth disease is a viral illness that usually affects children between the ages of five and fifteen, although older teenagers and adults can also contract the illness if they are not immune to it. The illness usually produces a red rash on the face that makes it look as if the person has a slapped cheek; sometimes, fifth disease is referred to as "slapped cheek disease." Usually, the rash will later spread to the trunk, arms, and legs. Fifth disease derives its name from its historical classification as the fifth of the classical childhood skin rashes.

In 1975, it was discovered that the human parvovirus B19 is the cause of fifth disease (which is also known as Erythema Infectiosum). However, it is not the same parvovirus that affects animals. Parvovirus cannot be passed from humans to animals, or from animals to humans. Outbreaks of parvovirus tend to happen in the late winter and early spring; however, there can be sporadic cases any time throughout the year.

Fifth disease begins with a low-grade fever, headache, and mild cold-like symptoms (such as a stuffy or runny nose). These symptoms pass, and the illness seems to be gone until the bright red rashes appear on the cheeks a few days later. Children under ten years of age are most likely to get the rash.

A person with a parvovirus infection is most contagious before the rash appears (either during the incubation time or during the time when the individual may only have mild respiratory symptoms). The incubation period ranges from four to twenty-eight days, with the average being sixteen to seventeen days. Because the rash is due to an immune reaction that occurs after the infection has passed, the individual is usually not contagious once the rash appears. It can take one to three weeks for the rash to completely clear. Stimuli such as sunlight, heat, exercise, and stress can reactivate the rash until it completely fades. Other symptoms that may occur with fifth disease are swollen glands, red eyes, sore throat, and diarrhea. On rare occasions, the infected person could have rashes that look like blisters or bruises.