Cholera

Question 1

cholera

Answer 1

infectious disease transmitted to humans through the process of ingesting contaminated water or food

Question 2

what bacteria causes cholera

Answer 2

bacterium Vibrio cholerae

Question 3

what are reservoirs for Vibrio cholerae

Answer 3

aquatic environments - though it was humans

Question 4

is cholera still a problem

Answer 4

current problem
2008-10-Zimbabwe
2010-11-Haiti (earthquake introduced cholera)
2016-present -Yemen (large epidemic - bombing targeted water treatment plans)

Question 5

what are 3 factors that contribute to cholera

Answer 5

1. poverty
2. natural disaster
3. war

Question 6

what does vibrio cholerae do and describe its structure

Answer 6

induces an acute dehydrating diarrhea that can kill you in hours if fluids and salts are not replaced
(quite tolerant, not specific, toxin causes you to lose water from intestines, sudden onset, fatal)

Question 7

humans are susceptible to dehydration

Answer 7

5% - stop what doing
10% - get to hospital
15% - dead

Question 8

endemic

Answer 8

the constant presence of a disease or infectious agent within a geographic area (expect to see no. of cases in time)

Question 9

epidemic

Answer 9

the occurrence in an area of a disease/illness in excess to what may be expected on the basis of past experience for a given population (no. increasing)

Question 10

pandemic

Answer 10

worldwide epidemic affecting an exceptionally high proportion of the global population

Question 11

describe the transmission of cholera

Answer 11

quick from the onset - outcome *incubation period

Question 12

what does the cholera infection risk depend on

Answer 12

1. dose

2. neutralization of stomach acids

Question 13

who are most at risk of cholera

Answer 13

1. farmers, fisherman, laborers

2. poor and malnourished

Question 14

the death of a patient from cholera represents a failure of healthcare

Answer 14

death from cholera is due to dehydration, loss of fluids/electrolytes = no special treatment/medicine - only fluids and electrolytes - if healthcare cannot provide this it has failed on the most basic service

Question 15

how can we control cholera

Answer 15

handwashing facilities
correct disposal of waste
clean water supplies
basic culinary standards (food prep)

Question 16

how do natural disasters lead to cholera

Answer 16

humans in huge densities, failed infrastructure = unable to provide adequate sanitation/water/supplies

Question 17

what happened in the Bangladesh flooding

Answer 17

unable to keep water/sewage supplies separate

Question 18

describe cholera in the Victorian era (1837-1901)

Answer 18

cholera spread easily = impacted/alarmed society
lots of people doing good - ignored those affected
cholera affected poor in society - blamed

Question 19

Third Cholera Pandemic (1852-1860)

Answer 19

outbreaks in London - Broad Street outbreak investigated by John Snow was particularly deadly

Question 20

did people in the past know what cholera was and how it was caused

Answer 20

nobody knew what caused infectious diseases

Question 21

miasma theory

Answer 21

diseases were caused by miasma or bad air arising from organic decay, filth, or other environmental conditions

Question 22

what did Florence Nightingale (1820-1910) do

Answer 22

nurse - reduced mortality on the wards by removing water sewage that ran through the middle - emphasized the miasma theory

Question 23

why did we progress towards flush toilets and what problems did this cause

Answer 23

invented before towns and cities had sewage systems (didn’t need)
as towns got bigger - solid/wastes dumped in cesspits = overflowing&raquo_space; populisation of flush toilets = increase wate liquid in sewage // NO SEWAGE SYSTEM
layer of faeces - heats up - smell intolerable = put all waste into water = polluted waterways

Question 24

Great Stink (1858)

Answer 24

summer - the smell of untreated sewage almost cause the abandonment of the biggest city in the world

Question 25

how did Joseph Bazelgette (1819-1891) solve the great stink

Answer 25

created a sewage system - down towards the Thames | doubled diameter of pipes - advanced and lasted London until high rise buildings/ densities increased

Question 26

how can we put a sewage system in a low lying city - Chicago

Answer 26

raise the city

Question 27

what did John Snow (1813-1858) realise

Answer 27

knew breathing smell > lungs > respiratory system effects of cholera observed on digestive tract suspected miasma theory suspected water supplies

Question 28

what was the difference between the water companies

Answer 28

got water from different sources

Question 29

what did John Snow do to investigate the cholera outbreak at Broad Street pump in Soho

Answer 29

1. interview those affected by outbreak as well as those who did not become infected = traced to which water pumps people used 2. focused investigation on water sources 3. mapped areas near of well with no cases = discovered had independent water sources

Question 30

why did prisons and pubs have no cases of cholera

Answer 30

had own water pumps

Question 31

why were there some distant cases of cholera

Answer 31

people worked closer to pump / went to other ones due to cloudy/polluted water

Question 32

index case

Answer 32

the first disease case in an epidemic (patient zero)

Question 33

why was cholera thought to be caused by a living organism

Answer 33

could explain how multiplication could cause disease = accounted for the incubation period

Question 34

when was the golden age of microbiology and who made the biggest contributions

Answer 34

(1850-1890) Louis Pasteur Robert Koch

Question 35

Germ theory

Answer 35

disease caused by living organisms

Question 36

how did we discover germ theory

Answer 36

``` beer sometimes good/spoilt batch - yeast carries out fermentation noticed rods (bacteria) in spoilt batch - multiplied = living organisms spolit beer - similarily in human body ```

Question 37

what is Koch's Postulates

Answer 37

4 criteria designed to establish a causal relationship between a causative microbe and a disease

Question 38

what are Koch's Postulates

Answer 38

1. microorganism must be found in abundance in all organisms suffering from the disease (but not in healthy organisms) 2. microorganism must be isolated from a diseased organism and grown in pure culture (practical difficulties) 3. the cultured microorganism should cause disease when introduced into a healthy organism (ethical difficulties) 4. the microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent

Question 39

Epidemiology

Answer 39

the branch in medicine that deals with the study of causes, distribution, and control of disease in populations

Question 40

Prevalence

Answer 40

the number of cases in a given area at a designated time

Question 41

Incidence

Answer 41

the number of new cases of a disease occurring in a given population over a certain period of time (rate of increase in cases of a population)

Question 42

virulence

Answer 42

the relative ability of a microbe to cause harm

Question 43

epidemic curve

Answer 43

a histogram that describes an outbreak of disease by plotting the number of cases of disease by date of onset

Question 44

point source

Answer 44

infected from same source at same time (peak) - more clustered around source

Question 45

continuous source

Answer 45

rise with variation but continuous (scattered) - more clustered around source

Question 46

propagated source

Answer 46

infectious disease increase with time (time gaps = incubation period) (spread geographically from point of origin)