[This is one of the best general articles I’ve read on Lyme disease and the bitter controversy surrounding diagnosis and treatment. -egg]

Those facts are undisputed. But nearly everything else about Lyme disease—the symptoms, the diagnosis, the prevalence, the behavior of the borrelia spirochete after it infects the body, and the correct approach to treatment—is contested bitterly and publicly. Even the definition of Lyme disease, and the terminology used to describe it, has fuelled years of acrimonious debate. The conventional medical assessment is straightforward: in most cases, the tick bite causes a skin rash, called erythema migrans, which is easily identified by its bull’s-eye. If left untreated, the bacteria can spread to muscles, joints, the heart, and even the brain. Public-health officials say that a few weeks of antibiotic treatment will almost always wipe out the infection, and that relapses are rare. In this view, put forth in guidelines issued by the Infectious Diseases Society of America, Lyme is normally easy to treat and easy to cure.

For many people, though, the clinical situation is far more complicated. Some who have been infected with borrelia don’t notice the rash. Others—up to a quarter of those with Lyme, including Kaleigh Ahern—never even get one. Most troubling, some patients who are treated continue to suffer from a variety of symptoms long after their therapy has ended. Nobody really knows why they fail to get better. Infectious-disease experts refer to the phenomenon, which can affect up to twenty per cent of patients, as Post-Treatment Lyme Disease Syndrome. Researchers have attempted to resolve the mystery in experiments with monkeys, mice, and dogs; human studies are also under way. As the number of infections grows, so does the number of people struggling to figure out what is wrong with them.

via Michael Specter: The Growing Battle Over How to Treat Lyme Disease : The New Yorker.