The present disclosure provides methods and composition including vaccines, monoclonal antibodies, polyclonal antibodies, chimeric molecule of an extracellular fibrinogen binding protein (Efb) and targeted agent delivery pharmaceutical composition comprising at least a portion of a modified N-terminus region, at least a portion of a modified C-terminus region, or both, wherein the modified extracellular fibrinogen binding protein results in inhibiting the fibrinogen binding, C3 binding, or both or administering to a subject a pharmacologically effective amount of a vaccine in a pharmaceutically acceptable excipient, comprising a modified extracellular fibrinogen binding protein comprising at least a portion of a modified N-terminus region, at least a portion of a modified C-terminus region, or both, wherein the modified extracellular fibrinogen binding protein results in not shielding the staphylococcus bacterium from recognition by a phagocytic receptor.