HFM exists in the USA, too, but is rarely reported, it’s not considered “serious”, and CDC calls it “common”:
http://www.cdc.gov/ncidod/dvrd/revb/enterovirus/hfhf.htm
The strains in the USA don’t seem to cause problems. CDC cites past deadly outbreaks in Malaysia and Taiwan.
My daughter had it a couple years back. It is pretty common.