What are coxsackieviruses?

Coxsackieviruses belong to a large family called the enteroviruses (named for their tendency to thrive in the human intestine). The most famous member of this family is polio, which has caused childhood paralysis dating back from at least 1350 B.C. (Pediatric Infectious Diseases, Saunders 1992). There are more than two dozen specific species of coxsackieviruses, each causing a wide variety of symptoms. Most illnesses caused by coxsackieviruses are minor; some are quite serious.

Coxsackieviruses are the major cause of hand-foot-and-mouth syndrome, an illness common in children around the world -- especially in the summer and early fall. Classically, this results in painful blisters in the mouth, on the palms and fingers of the hands, on the soles of the feet, and/or in the diaper area, appearing 3 to 6 days after exposure. Ouch! These blisters are filled with active virus and usually last for 7 to 10 days. Most of the time the children's immune systems rally to defeat the virus, and the infection goes away without any serious complications. There is, however, a wide spectrum of other possibilities.

The most common sickness caused by coxsackieviruses is a nonspecific febrile illness. Children have a fever that lasts an average of 3 days. Sometimes the fever leaves for 2 or 3 days and then returns. Sometimes this is the only symptom, but sometimes children also have a headache or a sore throat. Some children vomit at the beginning of the illness, or say, "My tummy hurts!" Sometimes they have one or two loose stools. Sometimes they have muscle pains, especially in the legs. Usually not much is found on physical exam or blood test. The illness usually lasts for between 24 hours and 6 days, but not always. You can see why this illness is called nonspecific!

Coxsackieviruses can cause the common cold. They can also cause croup, bronchitis, pneumonia, hepatitis, pancreatitis, arthritis, diabetes, meningitis, encephalitis, temporary or permanent paralysis, and viral myocarditis -- to name some of the many possibilities. These infections can be extremely serious. Viral myocarditis is an infection of the heart muscle. When coxsackievirus causes myocarditis, the fatality rate is high (International Journal of Cardiology, May 1996).

Thankfully, the overwhelming majority of coxsackieviral infections are mild. Complete recovery is the rule, and serious disease is rare. The severity and symptom patterns of these infections tend to cluster in local outbreaks.