In the IPV group , 27 ( 12 % ) children shed serotype 1 poliovirus and 17 ( 8 % ) shed serotype 3 poliovirus compared with 43 ( 19 % ) and 57 ( 26 % ) in the no vaccine group ( risk ratio 062 , 95 % CI 040-097 , p = 00375 ; 030 , 018-049 , p < 00001 ) .