Paul W. Ewald

Paul W. Ewald is an evolutionary biologist, specializing in the evolution of infectious disease.

Ewald asserts, along with a growing body of peer reviewed studies published in mainstream scientific journals, that many common diseases of unknown origin are in fact the result of the presence of slowly acting infections caused by viruses, bacteria or protozoa. For example, cervical cancer can be caused by the human papilloma virus; some cases of liver cancer are caused by hepatitis C or B; the bacteria Helicobacter pylori has been proven to cause stomach ulcers. His research extends these findings to a wide variety of other ailments.

Ewald disagrees with the popular theory that genes alone dictate certain disease susceptibility. He says "A disease-causing gene that reduces survival and reproduction would normally eliminate itself over a number of generations." One example of this is schizophrenia; patients with the mental illness rarely reproduce. Schizophrenia may be caused by Borna virus. He argues that this disease would have already been eliminated if it were from a strictly genetic cause. He also points out that in the case of gene sharing identical twins where one develops breast cancer, the other twin has only a 20% chance of developing the disease.

His background in evolutionary biology helped form these theories, not to discredit a fateful case of diarrhea in the late 1970's. His first thought during this bout was that his body was using diarrhea to expel the pathogen and he should avoid anti-diarrheal medication. Looking at the problem from the standpoint of the organism, expulsion was not an evolutionary benefit. The only benefit to the pathogen causing the sickness would be the potential transmission to other hosts; much like the particulate expelled during coughing, diarrhea can be a means of distribution. This thinking sparked his curiosity of the evolutionary process of infections.

Another major influence has been the AIDS virus which is inactive for years (allowing it to spread) before terminal, chronic and deteriorative ailments incapacitate and finally kill the victim.

The alleged evolutionary disadvantage of homosexuality has led Ewald to argue that it might be caused by an as-yet undetected virus working in utero that triggers hormonal responses. (See pathogenic theory of homosexuality).

Paul W. Ewald received his B.Sc. in 1975 from the University of California, Irvine, in Biological Sciences. He received his Ph.D. in 1980 from the University of Washington, in Zoology, specialization in Ecology and Evolution. He is currently director of the program in Evolutionary Medicine at the Biology Department of the University of Louisville -.

Quotes

 * "It opens our eyes to many quite weird possibilities about disease that most medical scientists, tending to be unaware of current evolutionary thought, don't think of." - Paul W. Ewald

Popular books by Paul W. Ewald

 * Plague Time: The New Germ Theory of Disease, Anchor, 2002, ISBN 0-385-72184-6

Popular articles about Paul W. Ewald

 * Steve Mirsky, Profile: Paul W. Ewald, A Host with Infectious Ideas May 2001, Scientific American

Academic books and articles by Paul W. Ewald

 * Transmission Modes and the Evolution of Virulence, with special reference to Cholera, Influenza, and AIDS, in Human Nature, Volume 2, Number 1 (1991) pp. 1-30


 * Evolution of Infectious Disease, Oxford University Press, 1996, ISBN 0-19-511139-7


 * Emerging pathogens: Insights from evolutionary biology, Emerging Infectious Diseases 2:245-257. Ewald, P. W. 1995.


 * The evolution of virulence: a unifying link between ecology and parasitology Journal of Parasitology 81:659-669.


 * Ewald, P. W. 1996 Vaccines as evolutionary tools: The virulence-antigen strategy In, CONCEPTS IN VACCINE DEVELOPMENT, (S. H. E. Kaufmann, ed.), Walter de Gruyter & Co:Berlin, pages 1-25.


 * Alternative transmission modes and the evolution of virulence Paul W. Ewald and Giulio De Leo, in Adaptive Dynamics of Infectious Diseases: In Pursuit of Virulence Management Series: Cambridge Studies in Adaptive Dynamics (No. 2), Edited by Ulf Dieckmann, 2002, ISBN-10: 0521781655


 * Virulence Management in Humans Paul W. Ewald, in Adaptive Dynamics of Infectious Diseases: In Pursuit of Virulence Management Series: Cambridge Studies in Adaptive Dynamics (No. 2), Edited by Ulf Dieckmann, 2002, ISBN-10: 0521781655