Stricker and colleagues have "creatively" misread our study, in which 10 days and 20 days of doxycycline treatment were demonstrated to have similar efficacy in patients with erythema migrans. Efficacy was evaluated at 4 different, specific time points (20 days, 3 months, 12 months, and 30 months), as well as at the time of the last visit with the patient, in both an on-study and an intention-to-treat analysis. The sample size estimates were based, as explicitly stated in the manuscript, on the 12-month time point, and were met.

At last patient contact in our intention-to-treat analysis, the complete response rates for the 10-day and 20-day doxycycline groups were nearly identical (83.3% and 86.2%, respectively). The patients who were classified as partial responders had usually mild subjective symptoms, such as intermittent fatigue or arthralgias. "Healthy" control groups of adults without a history of Lyme disease have been found to have similar symptoms at comparable frequencies (1), suggesting that Lyme disease is one of a number of triggers of such symptoms or that our patients' symptoms were unrelated to their episode of Lyme disease. In either case, the take-home message is that symptoms in early Lyme disease sometimes resolve slowly but will do so at the same rate regardless of whether antibiotic therapy is extended beyond 10 days.

Stricker and colleagues suggest that patients who developed erythema migrans at a different skin location during a subsequent summer, as well as those who did not return for a particular study visit, should have been considered treatment failures. This would not have affected the study findings because the frequency of these events was similar across treatment groups. Erythema migrans, which is found in more than 90% of patients who meet the Centers for Disease Control and Prevention's case definition of Lyme disease if a complete skin examination is performed (2), is, however, not a manifestation of late Lyme disease; it can be recognized as a reinfection because the site of the new tick bite is usually readily identifiable.

There is no scientific evidence to justify prolonged antibiotic therapy for patients with any manifestation of Lyme disease, and our study and that of others (3) should further help to discourage such practice. In addition, antibiotics are no better than placebo in treating patients who carry the label of "chronic Lyme disease," probably because evidence indicates that this entity is not infectious (4). Shorter courses of antibiotic therapy are more convenient for the patient, less expensive, potentially safer, and less likely to promote the emergence of resistant bacteria in the community.