emerging viruses - Emily Flashcards
What is an emerging disease?
-A “real” emergence of a brand new disease
-A geographic emergence in an area not previously affected
-Disease can emerge in species formerly not considered affected
-An unexpected increase of disease incidence in a known area and a known species (which includes a change in pathogenicity)
What are some risk factors for pathogen emergence? (just give a couple)
-Rising human population density
-Increased travel (animals and humans)
-Trade
-Poor biosecurity
-Inadequate animal health management
-Growing antimicrobial use
-Poverty
-Changing dietary habits
-Climate change
How is agriculture changing that impacts the emergence of diseases?
Bigger operations for increasing demand, rising costs, and shipping of animals all can affect the emergence of diseases
What is one porcine virus that has become more of an issue due to changes in agriculture?
Porcine reproductive and respiratory syndrome virus (PRRSV)
What is the biggest reason that PRRSV has increased?
Decreasing number of swine farms but an increased herd size
What are 3 changes in swine industry demographics that facilitated an explosion in PRRSV?
- Increasing herd size
- Multiple-site production with long distance movements
- Widespread adoption of artificial insemination (“we spread semen all over the place” -Herpes guy)
What is a slow emerging disease in US dairy farms?
Bovine Leukemia Virus (BLV)
What is the increase in herd prevalence of BLV from 1975 to 2018?
66% up to 94.2%
What is a disease that is becoming more of an issue due to climate change and travel?
West Nile Virus (WNV) because it’s spread by mosquitoes
What are 3 processes that breach barriers and allow for increased transmission of WNV?
- Dispersal
- Evolution
- Environmental change
How many cases of WNV were confirmed in Alberta horses in 2023?
9 cases
Where did Blue Tongue Virus (BTV) start and spread to?
Started in Northern Africa, spread to the Netherlands (specifically BTV-8)
When was BTV-3 introduced in the Netherlands?
September 2023
What is BTV transmitted by?
Culicoides (aka no-see-ums aka teeny tiny mosquitoes)
What symptoms are seen in offspring born with BTV?
-Malformed and stillbirths
-Arthrogryposis (abnormal joints)
-Hydrocephaly
-Brachygnathia inferior (overshot jaw)
-Ankylosis (stiff joints)
-Torticollis (twisted neck)
-Scoliosis (deformed spine)
What are the characteristics of Schmallenberg virus (SBV)?
-Enveloped
-Segmented
-ssRNA (negative sense)
What family and genus does Schmallenberg virus belong to?
Family: Bunyaviridae
Genus: Othobunyavirus
Which other viruses is Schmallenberg virus related to?
Simbu serogroup viruses (Shamonda, Akabane, Aino viruses)
What percent homology does the L-segment of SBV share with Akabane virus?
69%
What percent homology does the M-segment of SBV share with Aino virus?
71%
What percent homology does the S-segment of SBV share with Shamonda virus?
97%
Are Bunyaviruses known to infect humans?
Yes and they’re BAD
What are common pathological findings in aborted fetuses with SBV in the CNS?
-Spinal cord hypoplasia
-Cerebrum and cerebellum hypoplasia
What other deformities are common in aborted fetuses with SBV?
Musculoskeletal deformities (torticollis, brachygnathia inferior, scoliosis, myositis)
What is SBV transmitted by?
Culicoides spp (teeny tiny guys again)
Which day post infection is a spike in body temperature likely to occur with SBV infection?
Day 4 post infection
What is Hendra virus (HeV)?
An emerging zoonotic virus that infects horses and humans
What is the natural host of HeV?
Fruit bats
What is the case fatality percentage of HeV in horses?
75%
What symptoms can occur in humans infected with HeV?
Mild influenza symptoms to fatal respiratory or neurological disease
How can humans get HeV from horses?
Through close contact during care or during necropsies of infected horses
Which group of people are most likely to get HeV?
US (vets) and im scared
Why are spillover events so hard to understand?
Because there are SO many factors that can lead to a spill over event (swiss cheese model)
What are some things that led to the spread of Porcine Epidemic Diarrhea Virus (PEDV)?
-Poor biosecurity
-Inadequate animal health management
-Travel
-Trade
-Changing dietary habits
What is a significant cause of the spread of PEDV?
The feeding of spray dried porcine plasma to other pigs
