Ticks are bothersome on their own, but they’re devastating when they carry pathogens — like those infecting beef and dairy cattle in parts of the United States.

A microscopic parasite called Theileria [thī-lir-Ē-ah] orientalis is being spread among livestock by the Asian Longhorned tick. Theileria destroys red blood cells, leaving cattle with pale gums (anemia), profound weakness and labored breathing.

The good news is that the infection doesn’t spread to humans. However, treatment options are limited. Most affected animals die, and those that survive can relapse at any time. That’s why tick containment is so important.

Cattle ranchers and dairy producers who suspect Theileria infection should call their veterinarian immediately. Tick control and single use of blood-contaminated equipment are the best means of prevention.