1. Lyme disease

2. Borrelia Borrelia burgdorferi sensu stricto Borrelia garinii Borrelia afzelii

3. Life cycle of ticks

5. Two adult deer ticks

6. Ticks are pretty small…

7. Stage one (early infection) Erythema migrans 3 days to 1 month following bite Occurs in 60-80% (ie doesn’t always occur) Expands to characteristic “bulls eye”

8. Stage one (early infection)

9. Not all rashes are Lyme disease Allergic reactions to tick saliva usually occur within hours to a few days after the tick bite, usually do not expand, and disappear within a few days. Erythema migrans persists longer, but usually subsides within 3-4 weeks.

10. Stage two (dissemination stage) Fatigue Fever Headache Muscle and joint pain Lymphadenopathy Secondary annular skin lesions

11. Stage three (persistent infection) Months or years following bite Typically involves intermittent episodes of joint pain Meningitis Bell's palsy, numbness, pain Cardiac arrhythmias Migratory pain to joints, tendons, muscle and bone.

12. Stage three (persistent infection) Rheumatological Chronic Lyme arthritis in11% - erosion of cartilage and/or bone Neurological Depression, disturbances in memory, mood, or sleep patterns, tingling, numbness

13. Diagnosis Serodiagnosis to detect anti-borrelia antibodies is not useful until in later stages of illness. B. burgdorferi can be cultured from 80% or more of biopsy specimens taken from early erythema migrans lesions. However, the diagnostic value of this procedure is limited because of the need for special bacteriologic media (BSK medium) and protracted observation of cultures.

14. Treatment Doxycycline Late treatment can result in persistent symptoms

15. Prevention Avoid tick-infested areas, especially in May, June, and July Insect repellent containing DEET Wear a hat and a long-sleeved shirt Walk in the centre of trails to avoid overhanging grass and brush. After being outdoors, remove clothing and wash and dry it at a high temperature Remove ticks Preventive antibiotic treatment with erythromycin or doxycycline?

16. Summary A third of patients don’t have a rash Stage 2 symptoms are vague Stage 3 consequences are serious Diagnosis is difficult Awareness of the disease is poor