Usually one called Coxsackie is the culprit. There are may strains of Coxsackie and you can get infections from each strain. The full infection with HFM consists of sores, curiously enough, on the hands, feet and in the mouth. Most kids with HFM aren't too sick, although some fever and the sores in the mouth can bother them. Occasionally, you'll find sores on the buttocks too.
Treatment is symptomatic only.
The whole thing lasts 3-5 days on average and goes away spontaneously. Antibiotics do not help. That is, it can be spread by hand contact from child to child as the virus is excreted in the stool and saliva. The above reply is for educational purposes only. It should not be viewed as a substitute for medical or professional advice.