<prompt> Positive Shicks test indicates that the person isImmune to diphtheriaHypersensitive to diphtheriaSusceptible to diphtheriaCarrier of diphtheria  <response>: Schick test: intradermal test to demonstrate circulating diphtheria antitoxin. This antitoxin may be present either due to previous infection or immunization. This test demonstrates the immunity or susceptibility of a person against diphtheria. Positive Schick test signifies that the person is susceptible to diphtheria due to the absence or lack of adequate amount of circulating antitoxin. Reference: Textbook of Microbiology; Baveja; 4th edition; Page no: 219, 220 