A new study by US scientists has shown that animals given antibiotics spread salmonella faster, and could be a risk to human health.
The study, by a team of researchers from Stanford University of Medicine, may signal another important reason for restricting routine use of animas in livestock.
The Stanford scientists found that salmonella-infected lab mice that were given antibiotics became sicker and began shedding far more bacteria in their feces than they had before.
While these so-called “superspreaders” the rest of the mice got sicker instead of better. The discovery of the superspreaders’ ability to remain asymptomatic “poses ominous questions about the widespread, routine use of sub-therapeutic doses of antibiotics in livestock,” say the researchers.
“We’ve shown that the immune state of an infected mouse given antibiotics can dictate how sick that mouse gets and also carries implications for disease transmission,” said Denise Monack, PhD, associate professor of microbiology and immunology and the study’s senior author. “If this holds true for livestock as well — and I think it will — it would have obvious public health implications. We need to think about the possibility that we’re not only selecting for antibiotic-resistant microbes, but also impairing the health of our livestock and increasing the spread of contagious pathogens among them and us.”
