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Flashcards in Emerging Infectious Diseases Deck (44)
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0
Q

How many new human diseases have emerged over the past 20 years?

A

At least 30.

1
Q

What percentage of human pathogens are zoonotic?

A

61%

2
Q

What 2 factors determine if a disease is emerging?

A
  • Previously unknown disease that suddenly appears (emerges) in a population.
  • Known disease that suddenly appears (emerges) in a new population.
3
Q

What determines a re-emerging disease?

A

Known disease, previously on the decline, that is becoming more common and will likely continue to do so.

4
Q

Where did the 2001 outbreak of Foot and Mouth disease occur?
During what time period?
When was the last outbreak in this area?

A
  • UK
  • February to October
  • 1967
5
Q

What was done to stop the Foot and Mouth disease outbreak?

A

Massive culling of animals.

6
Q

What are the 5 stages of cross-species disease emergency?

A
  • Pathogen exclusive to an animal reservoir.
  • Animal reservoir transmits to humans/other animals, but no transmission among them.
  • Animal reservoir transmits to humans/other animals with a few cycle of transmission among them.
  • Animal reservoir transmits to humans/other animals with sustained transmission among them.
  • Pathogen exclusive to humans/new animal reservoir.
7
Q

T/F: Many pathogens have multiple host species.

A

True

8
Q

What percentage of pathogens have only one known host?

A

37.3%

9
Q

What are 3 examples of stage 2 diseases? What are their reservoirs and dead-end hosts?

A
  • Rabies: Reservoirs-carnivores and chiroptera (bats); Dead-end hosts-cattle and horses
  • WNV, EEEV, WEEV: Reservoirs-birds; Dead-end hosts- humans, horses and dogs
  • Influenza H5N1: Reservoirs-waterfowl and poultry; Dead-end hosts-humans
10
Q

When and where was the first outbreak of H5N1 avian influenza?

A

1997, Hong Kong

11
Q

Where was the 2004 outbreak of avian influenza?

A

Southeast Asia

12
Q

What are 2 examples of stage 3 pathogens, their reservoirs and how they are transmitted?

A
  • Mycobacterium bovis: Reservoir-cattle, bison, elk; transmission-to people via respiratory route (poor human-to-human transmission).
  • Nipah virus: Reservoir-fruit bats; transmission-human-to-human and pig-to-pig.
13
Q

When and where did the Nipah virus emerge?

A

Sept 1998 - April 1999 in Malaysia

14
Q

Rapid transmission of Nipha virus between pigs was seen by what route?

A

Respiratory

15
Q

The Nipah virus outbreak had a human fatality rate of what percentage?
Many cases involved what?
Survivors often had what type of a sequelae?

A
  • 40%
  • Encephalitis
  • Neurological sequelae
16
Q

What are 3 examples of stage 4 pathogens, their reservoirs and transmission?

A
  • SARS (Sever Acute Respiratory Syndrome): Reservoir-fruit bats; transmission-efficient in humans
  • Schmallenberg virus: Reservoir-unknown; transmission-efficient in sheep, goats and cattle
  • 2009 Influenza H1N1 (Swine influenza): Reservoir-swine; transmission-very efficient in humans
17
Q

When was the first human case of swine influenza detected and where?
When and where were the first pig cases of swine influenza detected?

A
  • April 2009 in Mexico

- Late April 2009 in Canada

18
Q

When was the 2009 H1N1 outbreak officially declared pandemic by the WHO?

A

June 11, 2009

19
Q

What are 5 examples of stage 5 pathogens and their sources of origin?

A
  • HIV/AIDS: non-human primates
  • Measles: cattle
  • Smallpox: likely camels (camel pox)
  • Dengue fever: Old world primates
  • Yellow fever: African primates
20
Q

What are 4 drivers to pathogen emergence?

A
  • Land use changes
  • Food and agricultural systems
  • Environmental systems
  • Human behavior
21
Q

What are 4 determinants of emergence?

A
  • Pathogen: type of agent and mutation/change
  • Reservoir: Phylogenetic distance
  • Transmission: Reservoir size, pathogen prevalence and contact frequency
  • Host: Susceptibility
22
Q

Of the over 1400 species of pathogens known to infect humans, how many are zoonotic?

A

61%

23
Q

What percentage of emerging diseases of humans are zoonotic?

A

75%

24
Q

Zoonotic pathogens are twice as likely to be associated with what?

A

Emerging diseases

25
Q

What are 4 ways pathogens adapt and change?

A
  • Increased antibiotic resistance
  • Increased virulence
  • Mutations that enhance transmissibility within or between species
  • Evasion of host immunity
26
Q

Do you get the best transmission within a species or between species?

A

Within a species.

27
Q

T/F: Pathogens that cross between distantly related species often cause similar and less severe disease.

A

False - Very different and often more severe disease.

28
Q

Intensive agriculture has lead to what in regards to susceptibility?

A

A lot of genetically similar hosts, managed under the same conditions, will have the same susceptibility.

29
Q

In today’s society, do we see more or less populations with weakened immune systems?

A

More

30
Q

What are 3 factors that increase the probability of transmission from a reservoir to a new host?

A
  • Increasing abundance of the reservoir
  • Increasing pathogen prevalence in the reservoir
  • Increasing contact between the reservoir and the new host
31
Q

What is predicted to happen to the world meat production from 2010 to 2020?

A

It is predicted to double.

32
Q

What are 4 portals of entry for transboundary diseases?

A
  • Animals/animal products
  • Vectors
  • Fomites
  • People
33
Q

What are 2 factors involving development and changing ecosystems that have increased transmission?

A
  • Urbanization increases density of susceptible human populations.
  • Changing land use and climate influence water-borne and vector-borne disease transmission.
34
Q

What does animal-based tourism increase?

A

Contact with both domestic and wildlife species.

35
Q

Example of bioterrorism.

A

Anthrax in US 2001

36
Q

Example of Bio-crimes.

A

Salmonella of salad bar in OR.

37
Q

What is a possible disease that could be used for agroterrorism?

A

Foot and Mouth disease

38
Q

T/F: There are enough appropriately trained veterinarians capable of recognizing and treating exotic diseases of livestock in the US.

A

False - There are not enough.

39
Q

What are 2 things veterinarians are responsible for?

A
  • Responsible antimicrobial use.

- Educating clients and the public.

40
Q

Healthy pets equal what?

A

Healthy owners.

41
Q

Healthy food animals equal what?

A

Reduced burden of pathogens at slaughter.

42
Q

What are clinical veterinarians uniquely situated to detect?

A

Early-stage outbreaks of agricultural and zoonotic diseases.

43
Q

What are 5 ways animal disease outbreaks are typically controlled?

A
  • Mass culling
  • Test and slaughter
  • Quarantine
  • Vaccination/ring vaccination
  • Prophylactic antibiotic use