AT least one new disease is jumping the species barrier from animals to human beings every year, exposing people to emerging germs at a rate that may be unprecedented. The first work to catalogue the range of germs capable of infecting people has disclosed that 38 new human pathogens have emerged in the past 25 years. Three quarters of these, including Aids, avian flu, Sars and new variant CJD, originated as animal diseases. The survey, led by Mark Woolhouse, of the University of Edinburgh, has identified more than 1,400 pathogens that can cause disease in human beings, at least 800 of which crossed the species barrier from animals. While it is not known whether the rate at which diseases are jumping species is accelerating, Dr Woolhouse said it was impossible that human beings had been exposed to so many new pathogens so quickly through most of history.

Source: TimesOnline