I practice in Hunterdon County where, at last check, there is more Lyme disease than any other county in the state of NJ; NJ is 3rd in cases behind CT, and NY. When parents/patients ask me about testing the tick for lyme disease I tease them by responding " I don't know the dose of antibiotics for the tick. In Hunterdon County we know about 10-15% of ticks carry the bacteria causing Lyme, yet if the tick is attached more than 48 hours the risk to the patient is only 1%. Using prophylactic doxycycline for deer ticks was done on adult patients and not on pediatric patients so extrapolating its use is not based on science in kids. Blood tests have gotten a lot better but may not turn "positive" (since they measure antibody responses) for 2-3 weeks. Observation is okay. If in the period after the bite the patient develops a flu-like illness (fever, chills, body ache, joint aches) then it is prudent to start the antibiotic. I am also aware of patients being treated for "chronic Lyme" with multiple negative tests that had metastatic disease to the bone/joint. Almost all the patients I have treated for late signs, i.e. Bells palsy, or Lyme arthritis never remember finding a deer tick. In pediatric patients as much as 90% of Lyme patients develop the ECM rash, which is more than in adults (about half). It's time some poster here apply to medical school before giving medical advice!!!I think you can also have the tick tested to see if it carries the disease.