Benach's main area of research is the tick-borne spirochete Borrelia burgdorferi, which is the causative agent of Lyme disease.
Benach and Edward Bosler, Ph.D. collaborated in the dogged and dangerous work of gathering and testing ticks for disease-causing pathogens at the Mashomack Preserve on Shelter Island, off the coast of New York.
It was in the midgut of two of those ticks that Burgdorfer, looking for RMSF rickettsiae, noticed the “poorly stained, rather long, irregularly coiled spirochetes” that he realized might be the cause of the erythema chronicum migrans rash of Lyme disease.
Benach subsequently supplied Burgdorfer with more field-collected ticks from Shelter Island, along with sera from clinically diagnosed patients with Lyme disease.
[medical citation needed] Benach continues to work with borrelia organisms at the Center for Infectious Diseases, Department of Molecular Genetics and Microbiology, Stony Brook University.