Researchers in the University of Liverpool’s Institute of Infection and Global Health used a big data approach to review existing studies contained in the Liverpool ENHanCEd Infectious Diseases (EID2) database to examine the relationship between how long a species has been domesticated and how many diseases affect that species and humans.

Dr. Marie McIntyre, an epidemiologist involved in the study, noted that “Using data in this way can help us address the major threat of new diseases and the spread of existing diseases caused by climate change.

“Vast amounts of research are being carried out in this field, yet it isn’t easy to search or draw patterns from it. As with this research into domestic animals, a database can help by bringing huge amounts of evidence together in one place.”

The researchers were able to discern that cattle, a species that has been associated with humans for roughly 11,000 years, shares 34 parasites and pathogens that can affect humans and cattle. Dogs, however, a species that has been in domestication for roughly 17,000 years—6,000 years more than cattle—shared 71 parasites and pathogens that can be spread between humans and dogs.

The findings of this study suggest that the longer a species shares a relationship with humans, the more parasites and pathogens will affect both the species and humans. As a result, livestock and pets may provide a vital link in the emergence of new diseases that affect mankind.