Article notes - Parasites in a changing world

Question 1

What is a parasite

Answer 1

A parasite is an organism that causes damage to another organisms, the host, by stealing its energy

Question 2

What types of organisms may be parasites?

Answer 2

Any virus, certain fungi, roundworms, bacteria, arthropods, protozoa, flatworms, and only a few vertebrates are parasites.

Question 3

What types of organisms are hosts for parasites?

Answer 3

Every organism can be a host for parasites, as they affect all species on Earth

Question 4

Do most parasites infect humans (among possible host species)

Answer 4

No, only about 4% of parasites affect humans

Question 5

Is global change beneficial or detrimental for parasite populations?

Answer 5

Global change is detrimental for parasite populations as parasites are only able to live in a good condition, one where their host(s) are viable, and they can only tolerate a certain range of changing environment

Question 6

What additional challenge confronts parasites, that is not an issue for free-living organisms?

Answer 6

Another challenge that parasites have their environment conditions must be suitable for both the parasites and the parasite’s host(s). Some parasites have multiple hosts, and this means that the environment must be viable for each host.

Question 7

What is spillover?

Answer 7

A parasite being present in a host species that has not been historically found in
due to it being transferred from the original host.

Question 8

What is its significance to humans

Answer 8

Spillover is significant to humans as multiple emerging parasites have been able to infect humans like: COVID-19, SARS, Ebola, and HIV.

Question 9

In what types of locations (geographically) would you expect to observe spillover into humans

Answer 9

Any kind of human industries where humans are within a natural ecosystem, for
example: hunting, deforestation, wildlife dealers, and hikers, is where spillover would be expected

Question 10

Is spillover increasing or decreasing? why?

Answer 10

Spillover has been increasing due to the increase of human industries and human
stress on these natural environments. This causes more contact with these
parasites

Question 11

Describe the various outcomes (stages) of spillover into humans

Answer 11

Spillover occurs within 5 stages. Stage 1 is when the parasite is only involved in
animals. Stage 2 is where an infection from animal to human occurs but there is
no further infection beyond that human. Stage 3 is where animal to human
infection occurs and then human to human infection occurs but only a few cycles
occur due to it failing after a few more human infections. Stage 4 is the same as
stage 3 but now there are large outbreaks of human to human and it is more
efficient. Stage 5 is where human and human infection occurs and no need for
animal to human spillover.

Question 12

Do you think it is good or bad for parasites to go extinct? explain

Answer 12

It is a bad thing for parasites to go extinct as they are a vital component to the natural ecosystem, and with their absence this can cause an influx of hosts and disrupt the ecosystem and the energy chain.

Question 13

True or false? Viruses infect all cellular life on the planet

Answer 13

true

Question 14

True or false? When infectious spillover from wild populations into humans, they inevitably spread person to person

Answer 14

false

Question 15

When facing changing global conditions, what additional challenge confronts parasites, that is not an issue for free-living organisms?

Answer 15

parasites have certain hosts and without their host, the parasite will also be unable to live

Question 16

Explain a situation in which it would be bad for a population of parasites to go extinct

Answer 16

any population of parasites involved in nature/ecosystem as they help keep the balance of the ecosystem. for example a parasite that infects birds and changes their behavior to consume more fish, without it the fish population would grow and not be stabilized