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Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Thimerosal is a preservative that contains mercury and is used in multidose vials of conventional and novel H1N1 flu vaccines to prevent contamination when the vial is repeatedly used to extract the vaccine. Although thimerosal is being phased out as a vaccine preservative, it is still used in flu vaccines in low levels. There is no data that indicate thimerosal in these vaccines has caused autism or other problems in individuals. Consequently, the FDA has indicated the following:

• There is no convincing evidence of harm caused by the small doses of thimerosal preservative in influenza vaccines, except for minor effects like swelling and redness at the injection site.
• A study of influenza vaccination examining over 2,000 pregnant women demonstrated no adverse fetal effects associated with influenza vaccine.

However, single-dose vials and the nasal-mist formulations of both the seasonal and H1N1 vaccines contain no thimerosal. These vaccine options are available to individuals who still want thimerosal-free vaccine. There occasionally was a shortage of single-dose vials as occurred with the H1N1 pandemic vaccine, so the individual may need to request a vial and may need to wait for it to become available. In addition, the new intradermal vaccine has no thimerosal.

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Flu in Adults Flu (influenza) is an acute infection of the nose and throat airways. This infection may spread to the lungs. Flu is the most frequent cause of acute respirator...learn more >>

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