About 75% of the new diseases that have affected humans over the past 10 years have been caused by pathogens originating from an animal or from products of animal origin. Many of these diseases have the potential to spread through various means over long distances and to become global problems.
In addition a number of well known and preventable animal diseases that can be transmitted to humans (i.e. zoonoses) such as rabies, brucellosis, leishmaniasis and echinococcosis continue to occur in many countries especially in the developing world where they mostly affect the poorest segment of the human population. They cause a serious amount of deaths and millions of affected people every year.
All major zoonotic diseases prevent the efficient production of food of animal origin, particularly of much-needed proteins, and create obstacles to international trade in animals and animal products. They are thus an impediment to overall socioeconomic development. From way back veterinary medicine played a major role in the preventing of and interventions against animal diseases including zoonoses.
To read more about animal to human transmission of disease from the World Health Organization, please click here: http://www.who.int/zoonoses/vph/en/