L20

Question 1

endemic disease

Answer 1

constantly present - causes low level frequency of disease at regular intervals - flu, colds
scattered dots on map

Question 2

epidemic disease

Answer 2

sudden increase above the expected - chickenpox
scattered but also concentrated in some places (on map)

Question 3

pandemic disease

Answer 3

increase simultaneously over wide area (global) - AIDS, flue, Covid-19
scattered and very much concentrated (on map)

Question 4

mobidity rate

Answer 4

no. of individuals becoming ill

Question 5

mortality rate

Answer 5

relationship between deaths and cases

Question 6

common source epidemic

Answer 6

sharp rise to a peak and rapid decline - food poisoning

Question 7

propogated epidemic

Answer 7

slow rise and gradual decline - chickenpox, seasonality change

Question 8

two types of epidemic

Answer 8

common source
propagated

Question 9

herd immunity

Answer 9

resistance of a population to infection - due to immunity of the majority

Question 10

what three diseases major herd immunity

Answer 10

flu
polio
measles

Question 11

what percent of the population do you need vaccinated to have herd immunity for the flu?

Answer 11

90

Question 12

what percent of the population do you need vaccinated to have herd immunity for polio?

Answer 12

70

Question 13

what percent of the population do you need vaccinated to have herd immunity for measles?

Answer 13

90-95

Question 14

what is antigenic drift?

Answer 14

minor antigenic variation due to mutations that alter amino acid sequences

Question 15

antigenic shift

Answer 15

causes major changes in virus coat proteins - undergoes frequent exchange between different strains

Question 16

factors responsible for emergence of new pathogens and re-emergence of ‘old’ pathogens (7) - DEITMBB (date-himmmb)

Answer 16

demographics
economic development and changes in land use
international travel
transportation
microbial adaptation
biological warfare
breakdown of public health measures