Margaret Pittman was considered a "world-renowned expert on the subject of pertussis," and "a woman scientist ahead of her time" according to Linda Smallwood, Associate Director for Policy in CBER’s Office of Blood Research and Review.

Pioneering Work on Haemophilus influenzae

Haemophilus influenzae bacteria cause infections in humans ranging from asymptomatic respiratory infections to serious diseases such as meningitis. Children are particularly susceptible to this pathogen. In the early 1930s, Margaret Pittman-who retired from the Division of Biologics Standards in 1971 after 35 years of making significant scientific contributions-was doing postgraduate work at the Rockefeller Institute (RI) for Medical Research. While at the RI, she conducted pioneering research on the microbiology and immunology of infections caused by H. influenzae. She found that these bacteria existed in two forms-encapsulated (with a special coating) and unencapsulated. The unencapsulated bacteria, which generally caused either no illness at all or relatively mild respiratory infections and mucosal infections (such as sinusitis), frequently were found in the upper respiratory tract of adults. Pittman discovered six different varieties of the encapsulated H. influenzae organism and observed that only the type b encapsulated variety seemed to cause serious diseases in children. Pittman’s work formed the basis for development of an antiserum for invasive H. influenzae type b disease. The antiserum was the first effective therapy for this potentially fatal infection. The 1985 licensing of a polysaccharide vaccine for H. influenzae type b for use in preschool-aged children was a long-term outcome of Pittman’s early research on this pathogen. Research by John Robbins and colleagues, conducted at the Bureau of Biologics in the 1980s, led to development and licensing in 1987 of a polysaccharide-protein conjugate vaccine for H. influenzae type b that provided stronger protection than the simpler polysaccharide vaccine. In 1996, Robbins received the Albert Lasker Award for Clinical Medical Research for his work on the conjugate vaccine.

From left, Top row: "Hut" Hudson; Russell P. Miller; Edward Garlock; Aneas P. Collins; Ben T. Sockrider; Thomas F. Probey
From left, Second row: Glen Hefner; L.J. Bender; Sadie A. Carlin; Dr. Sarah E. Stewart; Marguerite Lyons; Gilbert E. Beard; Robert Forkish.
From left, Bottom row: Dr. Karl Habel; Dr. Margaret Pittman; Dr. William G. Workman; Dr. W. T. Harrison; Dr. Sara E. Branham; Dr. V. J. Dorsett; Dr. Bernice Eddy.
Testing the Potency of Pertussis Vaccine

Pertussis, also known as "whooping cough," is a potentially deadly respiratory infection that most commonly affects children. The illness can last for weeks and is characterized by a severe cough; some infected children are left with permanent neurological damage, and some die. Although scientists had been trying to develop a pertussis vaccine since the early 1900s, the difficulty in assessing its potency was a major stumbling block. Scientists had not been able to develop a potency test for pertussis vaccine, because they were unable to establish pertussis infection in a laboratory animal. In 1944, Margaret Pittman found that she could infect mice with pertussis by injecting pertussis bacteria into the mouse brain. She then used this knowledge to test the potency of a pertussis vaccine. Dr. Pittman developed a vaccine potency standard based on a "50 percent dose"-that is, the dose of vaccine that would result in the survival of 50 percent of mice infected with a certain number of pertussis bacteria. On January 1, 1949, manufacturers began using this “mouse protection test” for determining pertussis vaccine potency. Further, to make vaccine preparation easier, Pittman prepared an opacity standard for pertussis vaccine that could be used to estimate the number of bacteria in a vaccine, instead of laboriously counting the bacteria under a microscope.

Pyrogenicity Testing for Blood Products

In the early 1940s, the use of intravenous therapy using blood and blood products increased significantly because of the many wounded soldiers who needed treatment during World War II. Occasionally, pyrogenicity (fever reactions) occurred after this therapy. To investigate pyrogenicity in blood products, Margaret Pittman and Thomas Probey, at the Division of Biologics Control, studied the pyrogenicity of 28 types of bacteria isolated from blood plasma by using a rabbit pyrogen test. Pittman and Probey found that all of the bacteria were capable of producing fever but, because the effects of various types of bacteria differed widely, simply measuring the number of bacteria in plasma could not predict the pyrogenicity of the plasma. Based on these and other findings, Pittman and Probey collaborated with manufacturers to help define production techniques that resulted in pyrogen-free blood products.