There are six different sub-types of Coxsackie B, a virus named after the town in New York state in which it was discovered in 1948.

CNN: Why Are the Infants Dying?

It is not known if the Coxsackie B virus grows in the respiratory tract or in the gut -- so no one is sure if it is passed through mucus or feces.

CNN: Why Are the Infants Dying?