epidemiology of viral diseases

Question 1

epidemiology

Answer 1

is the branch of science that studies the frequency, distribution, and determinants of disease in populations

Question 2

purpose of epidemiology

Answer 2

• acquisition of information
• planning and monitoring
• assessment of the economic effects

Question 3

arbovirus

Answer 3

multiply in the arthropod vector

Question 4

cases

Answer 4

those animals suffering from a clinically diagnosable disease

Question 5

case-fatality rate

Answer 5

the number (%)of deaths among the clinically ill animals

Question 6

carrier

Answer 6

any animal that sheds an infectious agent without demonstrating clinical signs

Question 7

incubatory (acute) carriers

Answer 7

animals that excrete agent during the disease’s incubation period

Question 8

covalescent (chronic) carriers

Answer 8

animals that shed agent when they are recovering from disease

Question 9

communicable period

Answer 9

the time during which the infectious agent may be transferred, directly or indirectly, from an infected animal to another animal

Question 10

contagious disease

Answer 10

an infectious disease in which the pathogen may be transmitted from one host to another by direct or indirect contact

Question 11

dead-end host

Answer 11

one that is not involved in maintaining a virus

Question 12

disease

Answer 12

any disturbance of the normal structure or function of any part, organ, or system of the body that results in a characteristic set of symptoms and signs

Question 13

endemic

Answer 13

the constant or usually expected occurrence of a disease within a give geographic area or population

Question 14

epidemic

Answer 14

major increase in disease incidence affecting either a large number of animals or spreading over a large area

Question 15

exotic

Answer 15

a disease not known to occur in a particular country or geographic area

Question 16

field isolate

Answer 16

fresh virus isolate from the natural host

Question 17

fomites

Answer 17

inanimate objects other than vehicles involved in the transfer of infectious agents from one host to another

Question 18

incidence

Answer 18

the number of new cases that occur in a population over a specified period of time

Question 19

incubation period

Answer 19

the period of time between infection and the development of clinical signs and symptoms

Question 20

infection

Answer 20

invasion and multiplication of microorganisms in body tissue

Question 21

morbidity rate

Answer 21

percentage of animals in a population that develop clinical disease attributable to a particular pathogen over a specified period of time

Question 22

mortality rate

Answer 22

percentage of animals in a population that die from a particular disease over a specified period of time

Question 23

pandemic

Answer 23

a geographically widespread epidemic

Question 24

pathogen

Answer 24

any disease causing virus or microorganisms

Question 25

pathogenicity

Answer 25

ability of an organism to cause disease

Question 26

population

Answer 26

aggregation of animals

Question 27

prevalence

Answer 27

the number of occurrences of disease, infection, or related attributes in a population at a particular point in time

Question 28

reservoir

Answer 28

the organism or environment that normally harbors a pathogen

Question 29

screening

Answer 29

this is systematic diagnostic testing to detect asymptomatic or subclinical animals or individuals who appear healthy, for the purpose of control or prevention of disease

Question 30

source

Answer 30

the place from which a pathogen passes directly to a susceptible host

Question 31

sporadic disease

Answer 31

a disease that occurs irregularly and hapharzadly

Question 32

sylvatic

Answer 32

occurring in or affecting wild animals

Question 33

threshold level

Answer 33

the minimum concentration of a pathogen in the host's circulation that allows successful transmission to an arthropod vestor

Question 34

wild-type virus

Answer 34

denotes the original virus circulation in nature from which mutants arise

Question 35

zoonosis

Answer 35

a disease that primarily affects vertebrate animals but that

Question 36

seroepidemiology

Answer 36

is the use of serological data as the basis of epidemiological investigation

Question 37

contact transmission

Answer 37

this is the spread of infectious agents by direct or indirect contact

Question 38

vestor transmission

Answer 38

an arthropod that carries pathogenic organisms from infected host to another

Question 39

extrinsic incubation period

Answer 39

the time the pathogen spends in the arthropod vector

Question 40

vehical transmission

Answer 40

this is the transmission of infectious agents by a medium

Question 41

iatrogenic transmission

Answer 41

infection that is transferred during surgical and medical practice

Question 42

nosocomial infections

Answer 42

infections acquired within the veterinary hospital or clinic

Question 43

epidemiologic triad is made up of:

Answer 43

- host - agent - the environment

Question 44

herd immunity

Answer 44

refers to immunity conferred on a group or population as a result of the presence of immune individual within the population