Natalie

Question 1

What are emerging infectious diseases

Answer 1

• cluster of cases caused by emerging pathogens unknown to cause disease OR re-emerging pathogens previously caused disease but now with increased infectivity

Question 2

What increases risk of EID

Answer 2

• population growth
• mobility
• climate change
• pollution
• environmental degradation
• aging population

Question 3

How are majority of EID derived

Answer 3

in a 2 step process from animals = spillover and adaptation

Question 4

Climate change extending the geographic range of vectors

Answer 4

• rising temperatures allows insects to thrive in new regions
• rising temperatures can also support increased bite and survival rates
• Also has potential to wipe out populations in certain regions > desertification of sub-saharan Africa
• vectors flourish in warmer/wetter climate

Question 5

Climate change mediating changes in virus survival and transmission

Answer 5

• warmer temperatures/altered humidity can enhance viral stability/transmission rates
• higher temperatures can permit increased replication rates
• El nino = more cold phases = increased transmission of influenza

Question 6

Extreme weather events

Answer 6

• high temperature
• floods
• droughts

Question 7

High temperature associations

Answer 7

• altered vector activity and bite rates
• increased transmission risk
• altered extrinsic incubation period
• increased survival of adult female vectors

Question 8

Flooding

Answer 8

• increases stagnant water pools for mosquitos to lay eggs = increased breeding sites = increased vectors
• increased exposure to vector bites
• decreased tick vector populations
• some mosquito species have reproductive cycles associated with flooding > can lay eggs in flood water which remain viable for many years
• strong winds associated with flood may kill adult mosquitos

Question 9

Droughts

Answer 9

• mosquitos drawn into homes = increased exposure to vector bites
• increased transmission risk

Question 10

Thawing of permafrost

Answer 10

• may expose long-dormant viruses reintroducing pathogens we havent seen in millennia

Question 11

Climate change - Food security and water quality

Answer 11

• malnutrition = weakened immunity = more susceptible to viral infection
• reduces micronutrients in crops and increases contaminants
• increased food-borne pathogens
• storms can result in wastewater overflow = increased transmission of norovrisu and hepatitis

Question 12

Urbanisation, deforestation and industry

Answer 12

• increased contacts with wildlife
• loss of habitats causes animals/vectors to move into urban areas = increased exposure
• decreased biodiversity = disrupts ecosystem = vectors can dominate
• deforestation removes canopy layer = no protection from sun and rain = soil erosion = vector breeding groups

Question 13

Trafficking and eating of wild animals

Answer 13

• risk of close contact with wild animals
• pathogens can switch hosts during transport
• risk of cross-species animal-animal transmission

Question 14

Climate changing causing disruptions in healthcare

Answer 14

• poor socioeconomic situations become exacerbated in climate-related disasters
• exacerbates viral disease burdens
• major problem in Pacific nations

Question 15

Likely characteristics of viruses that may cause a pandemic

Answer 15

• high replication rate
• RNA virus = high mutation
• zoonotic
• asymptomatic
• airborne
• can evade the immune system
• moderate mortality rate

Question 16

Air pollution

Answer 16

chronic exposure to air pollution = induced inflammation and oxidative stress = impaired immune function = increased respiratory disease burden

Question 17

Factors climate change can impact

Answer 17

• incubation periods
• vector:host ratio
• vector survival
• biting rate

Question 18

Temperature and RNAi efficiency

Answer 18

• RNAi suppresses viral replication of arboviruses
• lower RNAi efficiency at higher temperatures = increased replication = transmission

Question 19

Nipah virus example

Answer 19

• enveloped pleomorphic virus
• non-segmented ssRNA-
• route of transmission = bodily fluids or infected animals
• reservoir = fruit bat
• high population density mediates high rate of transmission
• deforestation = fruit bat moves to urban areas = pigs and humans eat fruit which have been bitten by bat = increased incidence

Question 20

Rabies example

Answer 20

• ssRNA
• circulates via interaction between domesticated and stray dogs along with wild animal interactions
• transmitted via saliva and bite of an infected host
• symptoms = anxiety, bewilderment, hallucination and hydrophobia
• urbanisation = increased pets = increased risk
• urbanisation = increased waste accumulation = increased food and habitats for rabies vectors

Question 21

potential Characteristics of pandemic viruses and PHEIC agents

Answer 21

• likely to be a zoonotic spillover events due to a lack of pre-existing immunity
• potentially an avian influenza virus as this is what all pandemics have been due to uncontrollable reservoirs
• airborne

Question 22

Preparing for future pandemics

Answer 22

• surveillance and metagenomics of reservoirs
• development of animal models for viruses that may cause pandemics
• research to understand molecular virology
• early stage development and testing in animal models
• development of broad antivirals as a first line of defense