Chinese researchers found that Tibetan sheep, making up about one-third of China's total sheep population, could transmit deadly bacteria to humans.

A study published on Thursday in the journal PLOS Neglected Tropical Diseases revealed that the plague caused by Y. pestis could be transferred from Himalayan marmot to sheep and then to human.

Li Wei's team from Chinese Center for Disease Control and Prevention extracted the genomic DNA from 38 strains of Y. pestisisolated from Tibetan sheep, Himalayan marmots, and humans.

Humans. Y. pestis isolated from Tibetan sheep and local marmots all were found to belong to the strain of human plague, according to the study.

The exact pathway of transmission of how the bacterium transmits still needs further study. However, researchers found that Tibetan sheep had a habit of licking the bodies of dead rodents such as marmots, possibly as a means of ingesting micronutrients in the plateau.

Transmission between marmot and sheep can also occur through fleas biting marmots and then carrying the disease onward.

The transmission from sheep to human is associated with the skinning, butchering, and eating under-cooked sheep meat.

The Tibetan sheep plague has some novel features, such as a complex transmission route, an extended epizootic period, and the possibility of transmission across long distances, so the hazards of Tibetan sheep plague should not be underestimated, according to the researchers.