Blood and Plasma Products, AIDS and the Blood Supply

by Food and Drug Administration (FDA)

(Page 2 of 2)

Pertussis Vaccine

Whooping cough (pertussis) vaccine had been available since 1915, but results from its use were not entirely satisfactory. There were many concerns regarding the potency of the vaccine. A CBER researcher named Dr. Margaret Pittman helped improve the vaccine in 1944. By 1949, manufacturers were able to sell whooping cough vaccine approved on potency as well as on safety and sterility.

CBER licensed the vaccine that is in use today on July 31, 1996. It is the first acellular pertussis vaccine for use in infants and children two months of age and older for the primary series of immunizations. This new vaccine contains only the parts of the pertussis bacterium thought to be important for immunity. So it protects infants against whooping cough while causing fewer side effects than the whole-cell pertussis vaccines that were previously on the market.

Blood and Plasma Products

From the 1950s through the 1970s, evidence indicated that the blood obtained from commercial blood banks carried a greater risk of hepatitis transmission. This led to more careful testing, and to increased regulation of blood to further protect the blood supply.

According to John Finlayson, Ph.D., associate director for science in CBER's Office of Blood Research and Review, "Hepatitis loomed very large. Most of us talked about serum hepatitis and that it was a very large threat post-transfusion," says Finlayson. "We had no tests for hepatitis A, no tests for hepatitis B, and of course, hepatitis C had not even been discovered. So that was a very big challenge, and there was also the challenge that there could be post-transfusion bacterial infections."

During World War II, there were two major concerns-providing clean blood and preserving blood plasma. But when soldiers were transfused, they had no guarantee of receiving clean blood because none of the tests used today were available.

Furthermore, because plasma was pooled for preservation, one infected donor could contaminate an entire batch. In response, an American chemist named Dr. Edwin Joseph Cohn led a team that devised a method called fractionation. This separated the individual proteins out of plasma. The resulting protein products, known as plasma derivatives, can be given in response to specific medical needs and with a high degree of confidence that they are safe.

AIDS and the Blood Supply

Safeguards over the years for blood donor screening and blood collection, processing, and testing led to increased confidence and perhaps a relative degree of complacency in the United States concerning safety of the blood supply. Thus, the scientific and health-care community, as well as government agencies and the public, were not prepared when AIDS emerged with full fury in the 1980s.

Blood transfusions became suspect, and improved screening tests for donated blood were necessary to protect the American people. CBER researchers and the blood and medical product industries responded to the challenge. The first test kit to detect HIV, the virus that causes AIDS, in donated blood was licensed in 1985. Inspections of blood banks were increased to ensure compliance with strict screening and processing procedures. Now, highly sensitive and specific nucleic acid-based tests allow the presence of hepatitis and HIV to be detected more rapidly.

Challenges for the 21st Century

Recent advances in technology have opened the doors to many other exciting areas in science. For example, gene therapy now allows us to actually alter the genetic makeup of a cell. Philip Noguchi, M.D., director of CBER's Division of Cellular and Gene Therapies, says, "Instead of giving a person interferon-which is a protein used to treat certain cancers and other diseases-why not give the person the gene and then his own body will actually start to make the protein, and might never have to replace it again? That's one of the very intriguing theories of gene therapy."

Xenotransplantation, the transplantation of animal cells, tissues or organs into a human, offers new hope for an added source of organs. New vaccines are being developed and modified as new discoveries teach us more about the human immune system. And the genomics revolution has scarcely begun. The study of gene structures is leading to potentially effective treatments for a variety of serious diseases, including cancer, diabetes, and heart disease.

"New biological products such as vaccines and therapeutics have already improved the health of the public," says Kathryn Zoon, Ph.D., director of CBER. "The blood supply has never been safer. And, as we move through the 21st century, our strong leadership in science-based regulation, coordinated research, and the use of partnerships will continue to assure that safe and effective new biological products reach the public."

About the Author

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.