Lecture 21 Flashcards
What is the virome?
The collection of viruses within an individual, species or population
What makes a virus emerge in a new population is a question
Biotic factors that shape the virome
- preferential host switching
- host age
What is preferential host switching
- viruses are more easily transmitted between closely related hosts
- parental host switching would mean that host taxonomy plays a key role in shaping virome composition
What is preferential host switching
- viruses are more easily transmitted between closely related hosts
- parental host switching would mean that host taxonomy plays a key role in shaping virome composition
Biotic factors that might shape the virome - host age
- most studied demographic factor that influences virome composition
- in humans gut viral diversity is age - dependent
Biotic factors that might shape the virome - age of birds
Abiotic factors that shape microbial community diversity
- studied best in marine systems
- ocean warming impacts on species distributions
Other key abiotic factors such as temperature, ocean depth, humidity, rainfall, elevation and seasonality may and all play a role in structuring the microbial community though modulating host population behavior or their role in transmission
- host biodiversity
- the latitudinal diversity gradient, the concent that host species richness increases towards the equator (and at poles there aren’t many species as they’d have to be super specialised)
- the dilution theory effect hypothesis suggests that there is a negative releationship between disease risk and host diversity. That is, high host diversity “dilutes” disease risk.
Dilution theory effect… only a hyposthties.. how do u prove it?
Viral diversity was determined by whether there was livestock not just distance
(Sampling over a long time periods is a good idea as snapshot veiws of viral diversity are unlikely to be representative at the species level
Dilution theory effect… only a hyposthties.. how do u prove it?
Viral diversity was determined by whether there was livestock not just distance
(Sampling over a long time periods is a good idea as snapshot veiws of viral diversity are unlikely to be representative at the species level
Brazil?
(In 2008 only rlly infected like 10 people to a pandemic in 2015 why)
In 2015 they killed a bunch of Miskitos which allowed another species to come in and occupy that space (urban areas) with lots of people
Zika virus
Why is it important to understand the factors that drive the composition of microbial communities ?
Disruption or invasion of ecological niches can lead to cross-species transmission (all past epidemics have been lead from disruption somehow)
Are bats special
We dont know
What is the ecology of bats which might potentially make them special
Bats harbour a high viral diversity relative to other mammalian orders
Factors leading to nipah virus emergence