Dr. Sparling’s early work helped define the genetics of antimicrobial resistance in the gonococcus, and the mechanisms of genetic transformation and of plasmid transfer in the gonococcus. Subsequent work focused on the genetics of the outer membrane of gonococci, with emphasis on the porin protein and of the several iron-regulated receptors for binding and transporting iron and heme from sources available in humans. Studies in male human volunteers established that either the transferrin or lactoferrin receptor was essential for initiating infection in the urethra, and that expression of both receptors provided a competitive advantage compared to expression of only the transferin receptor. Other studies focused on the function of genes in the TonB family; of the secretin PilQ; and of the importance of LOS structure to serum resistance. Current studies with his colleagues are focused on the roles of PilC in adherence, and the possibility of constructing a vaccine to prevent gonorrhea. Recent work showed the importance of a vigorous innate and/or Th1 response in protecting female mice from genital gonorrhea. Currently he is PI and director of the SE Regional Center of Excellence in Biodefense and Emerging Infections (SERCEB), and also of the SE STI Cooperative Research Center, both based at UNC but regional in scope.