Applying the Epidemiological Triad

Question 1

What are the 3 parts of the epidemiological triad?

Answer 1

1. Environment.
2. Host.
3. Pathogen.

Question 2

What factor influences the environment portion of the epidemiological triad?

Answer 2

Climate change

Question 3

What factors influence the host portion of the epidemiological triad?

Answer 3

1. Host heterogeneity.
2. Multiple host species.

Question 4

Host Heterogeneity?

Answer 4

How different the hosts within a population are based on age, sex, health status, nutritional status, genetics, etc.

Question 5

What factors influences the pathogen portion of the epidemiological triad?

Answer 5

1. Pathogen biology.
2. Coinfection.
3. Evolution.

Question 6

What factors influence the relationship between the host and pathogen in the epidemiological triad?

Answer 6

1. Vector biology.
2. Range expansion.

Question 7

What are free-ranging hosts?

Answer 7

Host for a pathogen that are able to move freely due to being wild or feral, making them difficult to monitor, access, treat, or control.

Question 8

What is the host for the saiga antelope MME?

Answer 8

Pregnant Saiga antelope.

Question 9

What is the pathogen for the saiga antelope MME?

Answer 9

Pasteurella multocida, a bacteria that is commensal in the nasal passageway of the saiga antelope.

Question 10

What is the environment for the saiga antelope MME?

Answer 10

Slightly increased humidity and temperature as compared to the past 40 years, causing Pasteurella multocida to overgrow and cause disease.

Question 11

What are the steps for the future concerning Saiga antelope MMEs?

Answer 11

1. Reduce other threats to the Saiga antelope (poaching, livestock diseases).
2. Monitor the current population as the next MME approaches.
3. Include all stakeholders in all conversations.

Question 12

What should most pathogens be classified as?

Answer 12

Multi-host instead of domestic, human, or wild.

Question 13

What was the COD for the birds in the MME in the 1990’s at man-made water bodies across the SE?

Answer 13

Avian Vacuolar Myelinopathy.
*Neurological Impairment was observed before death.

Question 14

What was a shared characteristic of all the water bodies other than being man-made and in the Southeastern U.S.?

Answer 14

They all had H.verticillata plants, an invasive and submerged water plant, growing in them.

Question 15

What lives on the leaves of H.verticillata?

Answer 15

A.hydrillicola, a cyanobacteria.

Question 16

What characteristic of A.hydrillicola led to the MME of the birds?

Answer 16

When in the presence of bromine or a bromine containing compound, the cyanobacteria secretes aetokthonotoxin (AETX).

Question 17

Where did the bromine come from?

Answer 17

Agriculture run-off.

Question 18

What was the host in the bird MME in the 1990’s at man-made water bodies across the SE?

Answer 18

1. Birds of prey.
2. Waterfowl.
3. Fish.

Question 19

What was the pathogen in the bird MME in the 1990’s at man-made water bodies across the SE?

Answer 19

AETX.

Question 20

What was the environment in the bird MME in the 1990’s at man-made water bodies across the SE?

Answer 20

Freshwater with high levels of bromine and an abundance of H.verticillata plants.