IMED1004 6- Epidemiology Exam Questions and Answers Solved Correctly Rated A+
Define epidemiology - Answers The study of disease in a population and factors that influence a
disease's frequency and distribution.
Define incidence - Answers The number of individuals who develop a specific disease or experience a
specific health-related event during a period of time.
Define prevalence - Answers total number of individuals in a population who have a disease.
Define recurrence - Answers How many times a disease is coming back
Define mortality rate - Answers Number/% of deaths in given population
Define morbidity rate - Answers Number/% of people who have complications/illness.
Define outbreak - Answers Occurrence of cases of disease in excess of that normally expected in a
defined community, area or season.
Define epidemic - Answers A sudden increase in the number of cases of a specific disease, beyond what
is considered to be a normal number, rapid spread.
Define a common source epidemic - Answers A single contaminated site gives rise to it. E.g. cholera in
drinking fountain London. Once source is eliminated, cases will be reported for a time period approx to
one incubation period.
Define host-to-host epidemic - Answers Spread from infected to uninfected individuals. No single
source. Start slowly and picks up speed.
Define epidemic threshold - Answers the minimum proportion of population that must be immune to
specific pathogen to prevent an epidemic. E.g. 90% for flu, 70% for polio.
Define pandemic - Answers Widely distributed, multi-continent epidemics.
Define endemic - Answers Always present in a particular area, usually at a lower level.
Define antigenic drift - Answers A minor genetic change in antigen make up of a virus due to random
mutations (error). Immune memory against an original antigen may no longer confer protection.
Define antigenic shift and example with Influenza A - Answers A major change when gene segments
from different strains of virus recombine to create a new strain, when infecting a cell at the same time.
E.g. H2N2 + H8N8 can give rise to H2N8 and H8N2.
How does a case definition help - Answers Helps authorities determine if unusual cases are related. It is
a list of common symptoms for a particular medical condition. A standard criteria for categorising an
individual as a case.
What three characteristics provide clues of a new disease's identity. - Answers Time, place and personal.
Define epidemiology - Answers The study of disease in a population and factors that influence a
disease's frequency and distribution.
Define incidence - Answers The number of individuals who develop a specific disease or experience a
specific health-related event during a period of time.
Define prevalence - Answers total number of individuals in a population who have a disease.
Define recurrence - Answers How many times a disease is coming back
Define mortality rate - Answers Number/% of deaths in given population
Define morbidity rate - Answers Number/% of people who have complications/illness.
Define outbreak - Answers Occurrence of cases of disease in excess of that normally expected in a
defined community, area or season.
Define epidemic - Answers A sudden increase in the number of cases of a specific disease, beyond what
is considered to be a normal number, rapid spread.
Define a common source epidemic - Answers A single contaminated site gives rise to it. E.g. cholera in
drinking fountain London. Once source is eliminated, cases will be reported for a time period approx to
one incubation period.
Define host-to-host epidemic - Answers Spread from infected to uninfected individuals. No single
source. Start slowly and picks up speed.
Define epidemic threshold - Answers the minimum proportion of population that must be immune to
specific pathogen to prevent an epidemic. E.g. 90% for flu, 70% for polio.
Define pandemic - Answers Widely distributed, multi-continent epidemics.
Define endemic - Answers Always present in a particular area, usually at a lower level.
Define antigenic drift - Answers A minor genetic change in antigen make up of a virus due to random
mutations (error). Immune memory against an original antigen may no longer confer protection.
Define antigenic shift and example with Influenza A - Answers A major change when gene segments
from different strains of virus recombine to create a new strain, when infecting a cell at the same time.
E.g. H2N2 + H8N8 can give rise to H2N8 and H8N2.
How does a case definition help - Answers Helps authorities determine if unusual cases are related. It is
a list of common symptoms for a particular medical condition. A standard criteria for categorising an
individual as a case.
What three characteristics provide clues of a new disease's identity. - Answers Time, place and personal.
