ACE and infection: Experiments assessing the ability of active and/or passive immunization against the virulence factors AS, Ace, Ebp pili and EfbA, to prevent or reduce the severity of the infection in animal models have been conducted by Schlievert, et al., 2010 [12], Singh, et al., 2010 [3], Pinkston, et al., 2014 [1] and Singh, et al., 2015 [2], respectively.