Epidemiology Flashcards
What factors contribute to the GLOBAL spread of disease?
Air travel
Population growth / overcrowding
Globalisation of food supply
Habitat alteration / deforestation
What’s the difference between epidemiologist and a healthcare worker?
Epidemiologist - thinks about population, public health, analyses data
Healthcare worker - thinks about individual health, medical expertise
If an emerging pathogen had an R0 of 30, would herd immunity need to be higher or lower than an emerging pathogen with R0 of 3?
We would need a HIGHER level of herd immunity.
As we increase R0, we increase the ability of transmission to occur!
Why have we been able to eradicate smallpox?
Global approach to vaccination
Public awareness
HUMAN ONLY RESERVOIR for smallpox - MAIN reason why we can eradicate it!
Compared to fomite (eg a contaminated cup), why is food a much more powerful disease transmitter?
Food as a vector - food source may be given to LARGE number of individuals and ingested
Increased ability to be transmitted to a WIDER range of individuals.
Tracking that disease outbreak will take time!
Most food borne and waterborne pathogens are ingested. (Gastrointestinal)
What natural defences do we have against these pathogens?
In the intestinal tract:
Stomach acid
Proteolytic enzymes
Bile salts - toxic to many bacteria
Micro flora in the colon
What broad category of microbes may be expected to grow on lemons, wine, bread?
Fungi!
Fungi like dry / acidic nutrients
Why would you NOT be inclined to experiment for bacterial food spillage microbes?
Bacteria prefer moist foods with a NEUTRAL pH = meat and fish etc.
By product of this spoilage is Hydrogen Sulphide which smells!
Which bacterial agents can produce 2 different forms of gastrointestinal disease, one which DOES NOT require the presence of pathogens in the body?
Bacillus cereus - soil microbe, can contaminate rice!
Why might there have been an increase in campylobacter spp, salmonella and E. coli during lockdown?
Barbecues are much more common in summer and when people staying at home - transmits pathogens!
Why might there have been a DECREASE in staphylococcal causes of food poisoning during lockdown?
Everybody was being far more careful with their hand hygiene!
What changes in the incidence of global Cholera have occurred during the covid 19 pandemic?
In Yemen for examples, cases have seemingly gone down but actually they have got much worse!
This is because data reflects the ability to REPORT the disease rather than the disease cases!!!
What is NOT an example of vehicle transmission during a disease outbreak?
Sexual contact
Herd immunity occurs when…
A sufficient number of individuals exhibit immunity to a particular disease
An Endemic disease is one that…
Is constantly present at LOW levels
