Guidelines
Localized Disease

Localized Disease

Recommendations

Order Lyme disease Serology if >7 days since tick bite (see Lyme Disease Serology below).

Commence treatment if clinical suspicion high.

If initial symptoms persist, test again for Lyme serology in 4 weeks.

Consult with Infectious Diseases and CPHO if necessary.

Adult Treatment

OR

OR

  • If penicillin allergic

Duration of Treatment

14 days

Increase duration to 21 days for immunocompromised individuals

More Information

  • Serology is not helpful if done within 7 days of a tick bite unless patient has had previous Lyme disease (very rare).
  • Serology for cases with Erythema migrans (EM) can be negative if prophylaxis or full treatment given.
  • Serology sensitivity for early Lyme disease (<30 days) is 46.3%.
  • Serology sensitivity improves for early disseminated disease (<3 months) to 89.7%.
  • Serology sensitivity further increases in late disseminated disease (>3 months) to 99.4%.
  • Lyme disease serology screening tests (ELISA) that are positive or indeterminate are sent to the National Microbiology Laboratory for western blot testing using CDC/PHAC criteria.
  • Contact with Infectious Disease Consultant for assistance in interpreting lab results from private and/or labs in the USA. Over 40% of healthy (non-infected) individuals will react falsely to private lab criteria.

European or Asian Lyme disease requires specialized testing. Please add travel history or contact the Infectious Disease Consultant