Rist Flashcards
___________ is the branch of biology that deals with relationships of organisms to one another and their physical surroundings.
ecology
__________ is a complex of living organisms, their physical environment, and all their interrelationships in a particular unit of space
ecosystem
The following are examples of which ecosystem services?
nutrient cycling
soil production
global water cycle
supporting services (these are the foundation of ecosystem services)
The following are examples of which ecosystem services?
food/pollination
fresh water
wood and fiber
fuel
provisioning services
The following are examples of which ecosystem services?
climate regulation
flood regulation
disease regulation
water purification
regulating services
The following are examples of which ecosystem services?
aesthetic
spiritual
educational
recreational
cultural services
A healthy ecosystem is one that is __________, that is, it has the ability to maintain structure and function over time in the face of external stress.
sustainable
___________ is the ability to meet current and future needs of ecosystem services
sustainability
T/F: a healthy ecosystem is one that is sustainably productive
true
How can we provide economic arguments for promoting sustainability and investing resources to maintain ecosystems?
by valuing ecosystem services
T/F: biological communities that are RICH in species are substantially HEALTHIER and MORE productive than those depleted of species, therefore we can use biodiversity as an indicator of ecosystem health
true
_______ is the global authority on species extinction risk.
IUCN
T/F: species extinction rate is occuring at 10 to 100 times the natural rate.
false – 100 to 1000 times the natural rate… really bad :(
Name 5 big threats to biodiversity
- habitat change/loss
- overexploitation
- climate change
- pollution
- biological invasions
T/F: threats to biodiversity occur over various time and spatial scales, and thus require action at levels ranging from local to international (overexploitation is more local level, whereas climate change is international)
true
T/F: healthy ecosystems have social AND economic value, so it is critical to recognize that we can allocate resources to maintain them sustainably
true
T/F: biodiversity is declining which indicates our ecosystems around the world are in trouble/not healthy/not sustainable/not productive
true
What are the 2 main goals of livestock production systems?
- produce enough safe and nutritious food to meet the needs of growing population
- maintain economic productivity
How do livestock production systems act as an intermediary and impact ecosystems, the human population, and resources?
Livestock production systems require services from the ecosystem in order to operate (land, water, crops/food)
They also GENERATE resources (food and manure)
how does climate change impact livestock production?
- different availability of livestock forage/feed (Some things are unable to grow some places d/t changes)
- heat stress (change in water consumption, feed intake, production levels, and reproduction)
- change in vector-borne disease patterns
We want to develop livestock production systems that do what 3 things:
- improve/maintain animal health and welfare
- reduce impact of livestock on climate/ecosystems
- mitigate impact of climate change/unhealthy ecosystems on livestock
T/F: companion animals receive resources from our ecosystem (food), provide resources to our ecosystem (working dogs), experience the impact of unhealthy ecosystems (heartworm, algal bloom toxicity), and even sometimes negatively impact our ecosystem (free-roaming cats and horses, released exotic pets).
true
T/F: sustainability in veterinary medicine is a vast field that has a plethora of knowledge for how we can practice veterinary medicine more sustainably.
false – this is an emerging field and we have tons more to contribute in the near future.
Describe the MEDICAL approach to infectious disease
Hint: 3 questions to ask and answer
- what are the symptoms?
- what body systems are affected?
- how severe is this disease?
this approach is important for diagnosis and treatment of disease
The following describes which approach to infectious disease?
“What is the cause of disease, who does it effect, where does transmission occur, and what patterns of disease do we see?” This is important in disease prevention and control within populations
epidemiologic
The ecological approach to infectious disease is important for prediction of when and where disease will occur. What 2 questions are commonly asked with this approach?
- why do the patterns of disease occur as they do?
- what variables are important in influencing disease patterns?
______________ is a set of biotic and abiotic conditions in the environment that define the limit of a species’ ability to survive.
niche
Overlap in time-space of niches determines what…
the dynamics of infectious diseases
____________ is the study of underlying principles that influence spatial and temporal patterns of diseases
disease ecology
Describe how a greater bird diversity leads to less spillover of WNV into human and equine populations.
Some bird species are more competent than others at maintaining WNV.
Having a greater bird diversity would mean that mosquitos have MORE opportunity to bite NON-COMPETENT birds, which would lead to lower WNV transmission within the bird populations, and subsequently less amplification of the virus in mosquitos and lower spillover into human and equine population
how do environmental conditions affect WNV transmission?
some environmental conditions SUPPORT faster repro rates or lengthen mosquito season, which impact their population size.
When we favor large mosquito population size, this leads to a greater risk of infection in the human and equine populations (especially if other factors are already present such as competent bird hosts or naive human/eq populations)
T/F: we can use ecology to predict disease patterns.
true
An _______________ is a disease that has appeared in a population for the first time, or that may have existed previously, but is rapidly increasing in incidence or geographic range.
emerging infectious disease (EID)
Why did infectious disease increase during/around the neolithic revolution?
populations began to become sedentary and agriculture and livestock domestication became prevalent, so disease emerged because people were surrounded by others and groups of animals were closer in proximity.
Why did infectious disease increase during/around the industrial revolution (more recent)?
because massive increases in population occurred.
T/F: emerging disease events are increasing and majority of them are caused by viral pathogens, most of which are zoonotic.
false – they are increasing, however, most of them are caused by bacteria and most are zoonotic.
________________ are the ecological, social, and economic conditions that facilitate disease emergence and transmission.
drivers of disease emergence
Name 10 of the most important drivers of disease emergence
- changes in land use and ag practices
- changes in human demographics and society
- poor population health
- hospitals and medical procedures
- pathogen evolution
- contamination
- international travel
- failure of public health programs
- international trade
- climate change
Fungal infections are most likely to be driven by…
poor population health
Bacterial infections are most likely to be driven by what 2 things?
- pathogen evolution (AMR, increased virulence)
- contamination of food sources or water supply
Changes in land use/ag practices and international travel are the drivers that most likely cause …
virus emergence
What is the biggest driver for zoonoses?
changes in land use and/or agriculture practices
T/F: the largest human population growth is in tropical and low-income countries where there is a higher disease burden in livestock.
true
Describe a demand-driven increase in consumption of animal products and how that impacts the way livestock are raised
higher income = higher demand
higher demand = more intensive practices
Intensification has what effect on the following things:
1. (increase or decrease) in endemic and epidemic diseases that are easier to control in intensive systems
2. (increase or decrease) in disease assoc. with crowding and environmental degradation
3. (increase of decrease) in food borne diseases that have little impact on animal host and are assoc. with poorly regulated intensification.
- decrease
- increase
- increase
________________ such as deforestation, infrastructure, urbanization, irrigation, etc. is an additional driver of livestock emerging infectious disease because there are increased livestock-wildlife interactions
anthropogenic land use
T/F: human and animal movement is a huge driver of livestock emerging infectious diseases (highly pathogenic avian influenza and foreign animal diseases)
true
The following describes which type of country/market?
a. high-income
b. developing market
c. traditional small-holder system
- intensifying and market-oriented production
- presence of several major infectious diseases
- endemic disease still common
- increased drug resistance
- variable regulation (vet service, infrastructure)
- erosion of genetic resources assoc. with disease resistance
b. developing market
high-income countries have intensive production, well-controlled endemic disease, increased drug resistance, expanded dist. of vector-borne dz, strong biosecurity regulations and vet services, and focus on quality, safety, and animal welfare.
What are 3 reasons we are seeing an overall reduction in livestock infectious diseases?
- more effective drugs and vaccines
- improvement in diagnostic technologies
- preventative medicine and herd/flock-based monitoring
What was the significance of the nipah virus that was initially prevalent in pigs and people in malaysia in 1998, but was found in humans in Bangladesh and India in 2001?
It raised the question of how this disease was being transmitted (bats –> fruit –> pigs –> people) and how it got from one area to another (different migration routes d/t drought).
1 million pigs were culled as a result and this destroyed a billion-dollar industry
What were the drivers for the nipah virus entering india and bangledesh?
- there was movement from small-scale pig farming to more intensive production.
More land was required and that created larger pig populations which allowed for disease to spread. - deforestation and drought –changed bat foraging patterns, putting infected bats in close proximity to growing malaysian pig industry
how did humans influence the spread of canine influenza H3N2?
they took their dogs to dog shows
it spread from GA and FL to other surrounding states
T/F: Canine influenza virus is considered endemic in the US
true
Why do we miss many pathogens when dogs are imported into the US?
we are focused mostly on rabies and screwworm and thus missing other pathogens OR pathogens are not being tracked by a surveillance program
How do natural disasters and climate change affect disease emergence?
people move/relocate or are displaced after natural disasters and bring their pets with them (and their diseases too)
how long did the SARS pandemic last?
november 2002-july 2003 (7 months total)
Where did SARS originate? (the source)
civets in Guangdong
so they were ordered to slaughter all in captivity and permanent ban was put on sale and consumption
Where did MERS-CoV first emerge?
Saudi Arabia in 2012
What was unique about the prevalence of MERS-CoV in Saudi Arabia?
A lot of the cases were in healthcare workers within saudi arabia, indicating that this infection was concentrated and nosocomial transmission was occurring
What were the 3 transmission routes for MERS-CoV?
- human-to-human (nosocomial/ in healthcare setting)
- community acquired (humans;close-contact)
- community acquired (from camels)
why did multiple studies identify high rates of seropositivity in dromedary camels in the Arabian penninsula, but no HUMAN diagnosis of MERS-CoV?
perhaps the virus had lower propensity to infect human cells
perhaps management is different
perhaps the human population health is different (diff susceptibilities)
T/F: there are 4 avian influenza virus types, many subtypes, lineages, clades, and subclades.
true
What 2 avian influenza viruses are currently circulating among people?
Avian influenza A H1N1
Avian Influenza A H3N2
What distinguishes highly pathogenic avian influenza from low pathogenic AI?
highly pathogenic AI has mortality of 90% within 24 hours
with LPAI, poultry show no signs or mild illness
If LPAI is not typically fatal for poultry, why are we so concerned about it?
because it has the potential to become HPAI through genetic mutation
which one has potential to cause human infections – HPAI or LPAI?
both!
but the high and low pathogenicity does not have to do with humans, only poultry
Why are live markets not good?
- they allow for mixture of species so some species carrying certain diseases can transmit them
- if the animals are not sold, they were brought home with the seller and then brought back – this is increasing the potential for disease spread
- at the market, lots of people come into contact with the animals being sold, so there is potential for animal to human transmission
The ___________ assesses the potential pandemic risk posed by influenza A viruses that currently circulate in animals but not in humans.
CDC influenza risk assessment tool
What is the current AI outbreak in the US?
highly pathogenic avian influenza H5N1
What are the 3 potential outcomes of lyme disease in humans based on the different surface proteins?
early localized disease – fever, headache, fatigue, erythema migrans
early disseminated disease – multiple skin lesions, cardiac arrhythmias, meningitis, headaches, muscle pain, facial paralysis, numb limbs
late disseminated disease – arthritis, mental fogginess, short term memory loss
What is post-treatment lyme disease syndrome?
lingering symptoms of fatigue, pain, joint/muscle aches, cognitive dysfunction that can last for weeks to months to years. it occurs in 10-20% of lyme disease cases.
what are the 2 MOST common effects of lyme disease in dogs?
renal and joint effects
rare reports of cardiac effects
dogs have no skin lesions, no hepatic effects, no neurological effects, and no post-treatment LD syndrome
T/F: lyme disease is considered emerging with almost 500,000 humans diagnosed and treated per year costing 0.7-1.3 billion dollars a year.
true
Seroprevalence of lyme in dogs is highest in what area of the US?
Northeast
T/F: we can use environmental factors (forest coverage, surface water coverage, elevation, annual temp, and population density) to predict the seroprevalence of lyme disease
true
T/F: habitat fragmentation decreases the seroprevalence of lyme disease because small mammals can no longer travel outside of their smaller habitats to transmit diseases.
false – habitat fragmentation helps maintain lyme.
