In 1943, soon after the Division of Biologics Control had moved to the new Bethesda, Maryland, campus of the NIH, Pittman began work on a standard of potency for a pertussis (whooping cough) vaccine.[9] In collaboration with Dr. Pearl Kindrick and Dr. Grace Eldering of the Michigan Department of Health, who had pioneered an effective pertussis vaccine but who had been unable to develop a potency assay, Pittman guided the 1949 initiation of U.S. standards for pertussis vaccine, which also became the basis of the international potency requirement of the World Health Organization.