Disease Transmission Flashcards Preview

Infectious Disease > Disease Transmission > Flashcards

Flashcards in Disease Transmission Deck (12):
1

Disease Triad

A image thumb
2

Define: Infectious Disease, Infestation, Contagious, Communicable, Zoonotic disease

Infectious Disease- caused by invasion of a living agent in/on host

Infestation- invasion but not multiplication of organism in/on host

Contagious- transmissible via direct or airborne routes

Communicable- caused by agent by direct or indirect routes

Zoonotic disease-transmitted animal to humans

3

Flow chart of infectious disease 

A image thumb
4

"chain of infection"

"chain of infection"

 

A image thumb
5

Resevoirs

Resevoir= habitat in which infectious agent lives/grows

Resevoirs MAINTAIN pathogens over time

Requirements for animal as resevoir:

  • is it infected naturally with pathogen
  • can species mainain pathogen over time
  • can it transmit disease to new host

6

Direct Transmission

Direct Transmission

  • Vertical: from a reservoir host to its offspring
    • congenital
    • perinatal
  • Horozontal: from the reservoir to a new host
    • direct contact
    • direct projection (sneeze)
    • airborne (air)

7

Vehicles vs. vectors

Vehicles: inanimate object which transferes disease

  • common vehicle-food or water
  • fomites- contaminated object (ex. doornob)

Vectors: living organism that transfers disease

  • mechanical- agent doesnt multiply in host
  • biological- angnt changes in host and these activities are required for transmission

***horozontal disease transmission

8

Emerging vs. re-emerging Disease

Emerging disease

  • previously unknown disease that emerges
  • know disease that appears in a new population

Re-emerging disease

  • known disease, becoming more common, and projected to continue progression

9

5 Stages of Cross-Species Disease Emergence

A image thumb
10

Determinanats of disease emergence

Determinanats of disease emergence

Pathogen

  • type of agent
    • most are zoonotic disease
  • pathogen adaptation
    • antibiotics resistance
    • mutations

Resevoirs

  • best transmission between same species
  • more likely spread between closely related species

Transmission

  • resevoir size
  • pathogen prevalence
  • contact frequency

Host

  • succeptibility

A image thumb
11

4 Portals of Entry for Transboundary Disease

4 Portals of Entry for Transboundary Disease

  • animals/animal products
  • vectors
  • fomites
  • people

12

Flow chart disease transmission

A image thumb