Single-dose doxycycline prophylaxis is reserved for bites occurring in counties where local Borrelia infection rates in nymphs are at least 20 percent.
D
Steps
schema.org/HowTo
01
Identify the county where the bite occurred, not just the patient's home county.
02
Cross-reference CDC Lyme case maps; the Northeast (ME-VA), upper Midwest (MN, WI), and parts of northern CA dominate.
03
If the county is not on those maps, the IDSA endemic criterion is generally not met.
04
Travel-acquired bites count: a bite picked up on a Maine vacation qualifies even if the patient lives in a non-endemic state.
05
Bring the bite location to the clinician; they make the endemic determination.