Health Risks of Spit and Snot

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Questions and Answers

Why do some germs cause more severe symptoms?

To weaken the host's immune system

To ensure the host's mobility and facilitate transmission

Because they depend less on host mobility (correct)

To increase the host's dependence on medicine

What can be done to reduce the harmfulness of infectious diseases?

Increasing medical research funding

Conducting more clinical trials

Developing stronger antibiotics

Implementing disease control methods that obstruct transmission strategies (correct)

What is the potential outcome of traditional methods of trying to eradicate germs?

Eradication of all germs

No change in germ populations

Increased host immunity

Breeding stronger germs (correct)

What is the innovative approach suggested by Dr. Paul Ewald?

Encouraging germs to evolve milder forms Signup and view all the answers

Why is it beneficial to obstruct the transmission strategies of harmful germs?

To encourage the evolution of milder forms of germs Signup and view all the answers

What is the common mode of transmission of the rhinovirus?

Through the air, like a sneeze Signup and view all the answers

What do scientists call the hypothesis that predicts germs will evolve to maximize their overall success?

The trade-off hypothesis Signup and view all the answers

What is the main reason why the 'just right' rhinovirus is most successful at transmitting itself to new hosts?

It multiplies quickly enough to ensure sufficient amounts of the virus to spread, but not so quickly that the host becomes too sick Signup and view all the answers

What is the result of the evolution of the rhinovirus, according to the trade-off hypothesis?

Less virulent forms of the virus will evolve Signup and view all the answers

What is the name of the parasite transmitted by mosquitoes?

Plasmodium Signup and view all the answers

What is the main reason why germs are found on almost every surface we come into contact with?

Because people often touch surfaces and transfer germs Signup and view all the answers

What is the common outcome of the common cold caused by the rhinovirus?

Mild symptoms that last for about a week Signup and view all the answers

What is the strategy used by germs to get from one host to the next?

Mode of transmission Signup and view all the answers

What is the result of a germ that multiplies very quickly within a host?

The host becomes severely ill Signup and view all the answers

Why is a mobile host beneficial for the rhinovirus?

Because the host is more likely to transmit the virus to others Signup and view all the answers

Study Notes

Germs and Disease Transmission

Germs are found on almost every surface we come into contact with and can interact with our bodies to cause disease.
Germs can be categorized into bacteria, fungi, protozoa, and viruses.

Evolution of Germs

The harmfulness or virulence of a germ is a result of evolution.
The mode of transmission, or strategy, used by a germ to get from one host to the next affects its evolution.
The trade-off hypothesis predicts that germs will evolve to maximize their overall success by achieving a balance between replicating within a host (causing virulence) and transmitting to a new host.

Rhinovirus Example

The rhinovirus is a common germ that causes up to half of all common colds.
It replicates in the upper airways and can be transmitted through the air.
The trade-off hypothesis suggests that less virulent forms of the rhinovirus will be favored by evolution because it relies on close contact to get to its next victim.

Modes of Transmission

Germs can use different modes of transmission, such as air, insects, water, or food.
The mode of transmission affects the evolution of the germ, with those that rely on host mobility (e.g., rhinovirus) typically causing milder symptoms.

Disease Control and Evolution

Simple disease control methods, such as mosquito proofing houses, establishing clean water systems, or staying home when sick, can obstruct the transmission strategies of harmful germs.
By reducing the transmission of germs, we can encourage their evolution towards milder forms.
This approach, suggested by evolutionary biologist Dr. Paul Ewald, could lead to a "win-win" situation where germs evolve to be less harmful.

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Description

A lovely day turns into a gross scenario when a stranger expels mucus and saliva, sending microscopic germs your way. Learn about the health risks associated with this unpleasant encounter.