About the size of a pinhead, the nymph stage of the dreaded deer tick—Ixodes scapularis—continues to wreak havoc, particularly in the Northeast and Upper Midwest, with a bite that can deliver the Lyme disease infection that causes painful symptoms for hundreds of thousands of people diagnosed with the disease each year. And if that is not enough, this blood-sucking parasite has also managed to crawl its way into the center of highly charged and sometimes acrimonious medical controversy.

Indeed, the fascinating story of how Lyme disease came to be identified, defined and deciphered too often gets overshadowed by heated disagreement about what this disorder is—and what it is not—and about how it should be diagnosed and treated.

In this issue of Proto, we focus on the science of Lyme, looking at evidence and data gleaned through years of basic research and clinical studies. We examine the current understanding of such issues as why arthritis and joint pain can persist after the apparent clearance of Lyme bacteria from the body. We look at genetic and evolutionary factors that may play a role in susceptibility to the disease and the virulence of symptoms. And we touch upon work now attempting to identify better diagnostic tools, which in turn can help inform how the illness needs to be treated.

Much of the pioneering work in Lyme disease can be attributed to Allen Steere, who was a young rheumatologist at Yale in the mid-1970s when he was asked to investigate a cluster of cases of juvenile rheumatoid arthritis—affecting young children and teenagers—in Lyme, Connecticut. In 1977, he published the first definitive description of Lyme disease. Today the lead Lyme investigator at Mass General’s Center of Immunology and Inflammatory Diseases, Steere has continued this journey, probing virtually every aspect of the disorder, including its clinical course, diagnosis, treatment and complications, particularly those associated with Lyme arthritis.

While great strides have been made in understanding and treating Lyme, little about the disease has ever been simple or straightforward. Progress has required a multidisciplinary approach involving rheumatologists, infectious disease specialists, immunologists, neurologists, cardiologists and psychiatrists as well as epidemiologists, entomologists and many others. And, as Steere reminds us, we have so much more to learn.

Still, as the number of people diagnosed with Lyme disease each year continues to rise, and as the disease keeps expanding geographically, we must persevere through the controversy, tapping the ideas, insights and best thinking of many if we are to make headway against this minute foe and the bacterium it carries.


Peter L. Slavin, M.D.
Massachusetts General Hospital


David F. Torchiana, M.D.
CEO and Chairman
Massachusetts General Physicians Organization