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This child has fifth disease or erythema infectiosum, also known as "slapped cheeks" due to the characteristics of the rash that develops in those with the disease. The term fifth disease comes from it being listed fifth on a classification of rashes seen in children. It is most often seen in children. Though generally mild, it can be serious for people with compromised immune systems.
Symptoms of the disease start pretty general and mild: headache, runny nose, and fever. The fairly characteristic rash should then follow after a few days. Some people will get a rash on more than their face, which can potentially cover most of the body. Intensity of the rash varies, but it is especially itchy if it appears on the bottom of the feet. It can last for at little as seven day, but in some cases can come and go over a period of weeks. It's also possible to get pain or swelling in the joints, but this is more characteristic of infected adults. One in five of those infected will be asymptomatic.
Fifth disease is transmitted through mucus, saliva, and sputum when you sneeze or cough. It can also be passed from mother to child during pregnancy and, in rare cases, this can lead to miscarriage. Generally, people can only pass on the disease during the early stages of the disease, and aren't contagious once the rash appears. Diagnosis is often done as soon as the doctor sees the slapped cheek rash, but blood testing can also be done. Treatment is limited to helping the symptoms, and the only prevention is normal cleanliness, like the washing of hands and covering up coughs and sneezes. Since it is generally such a mild disease, most people recover fine on their own. If you have had this disease, you should be immune from ever contracting it again.
This disease is caused by parvovirus B19. Though it shares a name with the very dangerous canine parvovirus type 2 seen in our pets, parvovirus B19 is clearly quite different. It is also only seen in humans, so cannot be passed to or from a pet.