In 1908 Russian microbiologist Ilya Mechnikov was a co-awardee for his discovery of probiotic strains of bacteria in yogurt cultures. The era of antibiotics arose shortly after Mechnikov's discovery that strongly influenced the intellectual climate of the mid-20th century toward promotion of antiseptic environments as best for maintaining shellfish health. Increasing incidences of antibiotic resistant strains of pathogens in the late 20th century to the present has led to a renaissance in probiotic research and it is now being applied to shellfish health. Promising strains of natural probiotic bacteria promoting health in larval and juvenile shellfish have been discovered in the last decade and it is likely we are at the dawn of an age of widespread probiotic use in shellfish aquaculture.