All of the following pertain to poliomyelitis, except

A)summer outbreaks in the United States have been recently increasing.
B)it is transmitted primarily by fecal contaminated water.
C)it can be asymptomatic or mild with headache, sore throat, fever, and nausea.
D)if virus enters the central nervous system, motor neurons can be infected and destroyed.
E)there are effective vaccines to prevent polio.