Definitions of communicable diseases dr.wah

Definitions of communicable diseases dr.wah

1. Definitions of Communicable Diseases Dr. Win Aye Hlaing Lecturer Department of Epidemiology University of Public Health, Yangon Monday, January 16, 2017 1

2. DEFINITIONS IN COMMUNICABLE DISEASE Communicable disease An illness due to a specific infectious agent or its toxic products that arise through transmission of that agent or its products from an infected person animal or inanimate reservoir to a susceptible host either directly or indirectly ( synonym: Infectious disease ) Communicable period The time during which an infectious agent may transfer directly or indirectly from an infected person to another person , from an infected animal to humans or from an infected person to animals including arthropods

3. 3. Infection The entry, lodgment, development and/or multiplication of an infectious agent in the host. It is not equivalent to infectious disease. The result may be in-apparent or manifest. (not synonym with contamination or infestation ) 4. Contamination The presence of infectious agent on a body surface, or in clothes, bedding , toys, surgical instruments or dressings or other inanimate articles or substances including water, milk and food 5. Infestation Lodgment , development and reproduction of arthropods on the surface of the body or in clothing. e.g. Lice, itch, mite and parasitic worms ( Ascariasis )

4. 6. Infectious disease A clinically manifest disease of man or animals resulting from an infection 7. Contagious disease A disease that is transmitted through contact. E.g. Scabies, Trachoma , STD, Leprosy, etc. 8. Exotic Disease , which are imported into a country in which they do not otherwise occur (E.g. rabies in United Kingdom ) 9. Sporadic - Irregularly and infrequently occurred cases, it may be a starting point of an epidemic

5. 10. E ndemic disease The constant presence of a disease or infectious agent within a given geographical area or population group. Hyperendemic represent a constant presence with relative high incidence [ with relatively high prevalence and incidence rates (Enzootic) ] 11. Outbreak Occurrence of more cases of disease than expected, in a given area, among a specific group of people, over a particular period of time. 12. Epidemic disease The occurrence in a community or region of cases of an illness (or an outbreak ) clear in excess of normal expectancy (Epizootic) 13. Pandemic An epidemic affecting a large proportion of the population. E.g. the entire nation, a continent or the world

6. 14. Incubation period The time interval between invasion by an infectious agent and appearance of the first symptom or sign of a disease 15. Latent period Incubation period of non-infectious diseases is called latent period. It is the time interval between the initiations of a disease to detection of a disease

7. 16. Pathogenicity The ability to produce overt disease, which is measured by the ratio of number of persons developed illness to the number exposed to infection 17. Virulence A measure of the severity of disease or the degree of pathogenecity of an infectious agent. It varies from very low to very high. Indicate by CFR or the ability of the agent to invade and damage tissues of the host

8. 18. Agent A substance, living or non-living, or a force, tangible or intangible, the excessive presence or relative lack of which may initiate or perpetuate a disease process. A disease may have a single, multiple or combined and complex agents 19. Reservoir Any person, animal, arthropod, plant or an environmental source ( or combination of these) in which an infectious agent normally live or multiply, on which it depends primary for survival, and which it reproduces itself in such manner that it can be transmitted to a susceptible host

9. 20 . Source The person, animal or object from which an infectious agent passes to a host .( Distinct from source of contamination ) 21. Sources of infection The places from which an infectious agent passes immediately to a susceptible host

10. 22. Notification Immediate intimation of the occurrence of a communicable disease by a responsible person to the local health authorities to take immediate action to prevent spread of disease 23. Reporting The reporting of occurrence of communicable disease by the local health personal to his higher authority ( HA-TMO-DHO-DG-Minister of Health-WHO) 24. Susceptible person A person or animal not possessing sufficient resistance to prevent contracting the infection or disease when exposed to an agent

11. 25. Isolation The separation for the period of communicability, of infected persons or animals from others, in such place and under such conditions as to prevent the direct or indirect conveyance of the infectious agent from those infected to those who are susceptible or who may spread the agent to others 26. Quarantine Restriction of the movements or activities of a well individual or animal who has been exposed to a communicable disease during the period of communicability of that disease and in such a manner that transmission of the disease should have occurred. The duration of the quarantine ordered shall be equivalent to the usual incubation period of the disease to which the susceptible person or animal was exposed

12. Monday, January 16, 2017 12 THANK YOU!!