Final Flashcards
What do the authors think made COVID-19 relatively unique from SARS-CoV-2?
-The ability of the virus to spread asymptomatically and presymptomatically
-(air travel) which allowed SARS-CoV-2 to have a rapid and global reach
How do you control for infected populations when you cannot tell who’s infected?
Mass testing
What is a disease? What are some possible causes of disease?
Function-impairing conditions that reduces survival or reproduction (fitness), a condition of a host– pathogens, parasites, parasitoids are possible causes of disease
What kinds of organisms and non-living things cause disease?
Bacteria, viruses, protists, fungi, prions, worms, ticks, lice, transmissible tumors
Organisms that are vertically transmitted over time from mother to child usually become what over time?
Mutualists, both organisms get mutual benefit from the relationship and host fitness is increased
Organisms that are horizontally transmitted, highly mobile with the ability to abandon the original host to jump to a new host (in and out of the body), are usually _____?
Parasitic
What are viruses made up of? What is their flow of information?
DNA → RNA → Protein
What do bacterial pathogens/parasites use to allow it to survive in the host? What do they do?
-Bacterial toxins –> secreted and damage tissues
-Antibiotics –> kills bacteria that are not the same species
What does polyphyletic mean? Why are protists polyphyletic?
-includes 2 convergent descendants but not common ancestor
-Protists are a large portion of eukaryotic diversity
-Malaria, Giardia, Amoebic dysentery (all from different ancestors but had convergent evolution)
-Almost anything can become a parasite or a pathogen if it makes sense to its ecology (costs and benefits)
-Malaria are more closely related to algae
What is a macroparasite? Can it make you sick?
-Macroparasites are organisms that have a parasitic life cycle like tapeworms, hookworms, lice, fleas, trematodes
-Macroparasites can make you sick if it overburdens you
more parasites → sick
less parasites → not really sick
What are parasitoids?
Parasitoids are macroparasites, organisms that has young that develop on or within another organism (the host), eventually killing it
How do you calculate R0 from the attack rate?
S(infinity) = e^-R0(attack rate)
-use ln to solve
What is TB caused by?
Bacterium, Mycobacterium tuberculosis
What does it mean when we say TB is in the latent phase?
Some level of TB exists in the person, but not enough to show symptoms or be infectious
How did we achieve lower TB levels in human populations?
-isolating patients
- antibiotics and vaccines
What phylum of organisms make up a large proportion of vectors?
Arthropods
Why are Aedes aegypti such efficient human vectors?
They are anthropophilic (attracted to the smell of humans), they can live in urban habitats near humans, and have high vector competence
What is the main vector that causes yellow fever and dengue to humans?
Aedes aegypti, mosquito that specializes on humans
At what stage of the life cycle does the tick become infected?
larval stage
Explain the difference between bottom-up and top-down control
Bottom-Up: lower trophic levels (eg. primary producers) control the distribution and abundance of higher trophic levels
Top-Down: higher trophic levels (eg. apex predators) control the distribution and abundance of lower trophic levels
One of the tropical neglected diseases is Dracunculiasis, caused by the guinea-worm, an endoparasite. How do we define its transmission?
Trophic Transmission: an intermediate host is consumed by a definitive host, transmitting a pathogen/parasite in the process to the new definitive host
Humans or other hosts can ingest guinea-worm by eating contaminated water or uncooked meat that have the infected copepods in/on the water/meat, these copepods have the guinea-worm inside them
What makes the river prawn different from a usual Lotka–Voltera model?
River prawns are generalist predators, meaning their abundance doesn’t rely on the snail prey abundance. If snail abundance went down, river prawns can still keep their populations at a high equilibrium since they can feed on other prey.
This means they are able to keep the snail densities at a lower equilibrium, indirectly keeping the blood flukes low as well
If prawns were specialist on snails, they might cause their own local extinction by reducing their prey population
Why do we see “damped oscillations” in the measles mathematical model (SEIR)?
Due to births– new babies are added to the population, like new susceptibles, can cause peak of infections
The models of real measles outbreaks do not match this? Why? If you were to draw the seasonality of the factor (that is variable) underneath the outbreaks what would it look like?
Transmission rate of measles is seasonal, which varies much more than birth rates
Transmission rates peak more variably
Birth rates included is also including seasonality of the disease, as birth accumulate (though the outbreak caused by a build up susceptibles causes less of a giant outbreak)