Frank Ryan

Frank Ryan, a British physician and writer, is the author of The Forgotten Plague, a study of tuberculosis, and Virus X,from which the following viewpoint is excerpted. Ryan examines why certain viruses, such as the Ebola virus, sometimes cause lethal outbreaks among humans and whether viruses could potentially cause the extinction of the human species. He theorizes that viruses have evolved to exist in a symbiotic relationship with many animals, causing no harm to their host but causing fatal illnesses to related animals that are potential competitors of the viral host. Therefore, he contends, primates and other animals may harbor viruses fatal to humans. The continuing expansion of humans into rain forests and other wilderness areas increases the chances of viral outbreaks, he asserts, while overcrowding in cities and other...