1. Epidemic curve (Epi – Curve )

3. خصوصيات منحني اپيدميولوژيك
در كجاي روند يك همه گيري هستيم.
اگر دوره كمون بيماري را مي دانيم مي توانيم بگوييم تماس كي اتفاق افتاده است.
مي توانيم بگوييم آيا يكبار تماس بوده يا ادامه دارد.
آيا همه گيري فرد به فرد هم منتقل شده است.
آياهر دوي موارد بالا همزمان اتفاق افتاده است؟

5. Epi curve characters
The shape and other features of an epidemic curve can suggest hypotheses about the time and source of exposure, the mode of transmission, and the causative agent.

6. sometimes classify epidemics
• Common source — Point — Intermittent — Continuous • Propagated • Mixed

7. Example of common source outbreak with point source exposure: Hepatitis A cases by date of onset, Fayetteville, Arkansas, November-December 1978, with log-normal curve superimposed

8. Example of common source outbreak with continuous exposure: Diarrheal illness in city residents by date of onset and character of stool, Cabool, Missouri, December 1989-January 1990

9. Example of the classic epidemic curve of a propagated epidemic: Measles cases by date of onset, Aberdeen, South Dakota, October 15, 1970-January 16, 1971

10. Example of a propagated epidemic that does not show the classic pattern: Infectious hepatitis cases by week of onset, Barren County, Kentucky, June 1970-April 1971

11. Example of a mixed epidemic: Shigella cases at a music festival by day of onset, Michigan, August 1988

12. Epidemic curve (Epi – Curve )

13. Seasonal occurrence of leptospirosis in humans in USA

14. Propagating

15. Sporadic

16. Endemic

17. Epidemic

18. Temporal occurrence of rabies in wildlife and dogs in USA