Disease Transmission

Question 1

Who discovered that cholera is transmitted by the fecal-oral route, and water?

Answer 1

John Snow (he does know something)

Question 2

Who established the modern concept of ‘germ theory’?

Answer 2

Robert Koch isolated the bacterium B. anthracis

Question 3

Who discovered transmission of disease by vectors? (hint: 2 people)

Answer 3

Ronald Ross and malaria
Walter Reed and yellow fever
both are transmitted by mosquitoes

Question 4

What is a reservoir?

Answer 4

Habitat in which an infectious agent normally lives, grows, and multiplies
ie. People, animals and the environment

Question 5

What must be true to classify an animal/environment/person as a reservoir?

Answer 5

1. Must be naturally infected with the pathogen
2. Must maintain the pathogen over time
3. Transmit disease to a new, susceptible host.

Question 6

How do reservoirs factor in to practical disease control?

Answer 6

1. Can an acceptable level of control be achieved without consideration of a reservoir?
2. If not, what populations constitute the reservoir?

Question 7

T/F: all sick animals are reservoirs

Answer 7

False.

Question 8

T/F: Clinically ill animals that are reservoir competent are infectious

Answer 8

True. Asymptomatic carriers can also be infectious

Question 9

What are the 2 main modes of disease transmission?

Answer 9

Horizontal and vertical

Question 10

What are the different types of vertical transmission?

Answer 10

Transplacental/transovarial

perinatal

Question 11

What are the different categories of horizontal transmission?

Answer 11

Direct and indirect

Question 12

what are the different types of indirect transmission? Is this horizontal or vertical transmission?

Answer 12

Horizontal transmission

Vehicle (inanimate object capable of spreading disease): fomite, common vehicle

Vector (living organism): Mechanical and biological

Question 13

What are the types of direct transmission? Is this an example of horizontal or vertical transmission?

Answer 13

Horizontal transmission

Projection and direct contact

Question 14

what is vertical transmission?

Answer 14

From a reservoir host to its offspring via TP or perinatal routes

Question 15

what is horizontal transmission?

Answer 15

From the reservoir host to a new host via direct or indirect (using an intermediary) routes.

Question 16

what is the difference between mechanical and biological vectors?

Answer 16

Mechanical: pathogen does not undergo part of its life cycle while in the vector

Biological: pathogen multiples while in the vector and is required for transmission.

Question 17

Which of the following is not included in veterinary public health? 
  A. biomedical research 
  B. non zoonotic animal diseases
  C. therapy animals 
  D. ectoparasites

Answer 17

All are apart of veterinary public health 
   also included: 
zoonotic diseases
foodborne pathogens
animal related injuries

Question 18

What is epizootiology?

Answer 18

the study of the distribution and determinants of disease and other health outcomes in animal populations