Disease Spread
Modes of Transmission
Chain of Infection
Cases and Carriers
Prevention Levels
100

What is endemic?

A disease that is always present in a specific geographic area 

100

What is direct transmission?

When an infected person comes into direct physical contact with another individual

100

What is an infectious agent?

Microorganism that causes the disease

100

What is an index case?

The first identified disease case by health authorities

100

What is primary prevention? 

Actions taken to stop the disease before it starts

200

What is epidemic?

A sudden increase in the number of disease cases that exceeds the expected level 

200

What is indirect transmission?

Transmission occurs through another object or organism 

200

What is a reservoir? 

Where the infectious agent normally lives, multiplies, and can potentially be transmitted to other hosts 

200

What is an active carrier? 

An infected person who shows symptoms and can transmit the disease 

200

What is secondary prevention? 

Actions to detect and treat the disease in its early stages, often before symptoms appear

300

What is pandemic?

A worldwide spread of a new disease 

300

What is airborne transmission?

When infectious particles remain in the air and are inhaled by individuals

300

What is a portal of exit? 

The path by which an infectious agent leaves its reservoir to potentially infect another host 

300

What is a healthy or passive carrier?

An infected person who shows no symptoms but can still transmit the disease 

300

What is a tertiary prevention? 

Actions to manage and reduce complications of an existing disease 

400

What is an outbreak?

An unexpected local rise in cases that could lead to an epidemic if not controlled

400

What is vector-borne transmission? 

Transmission through mosquitos or ticks 

400

What is a mode of transmission? 

The specific ways by which an infectious agent spreads from one host to another host 

400

What is an incubatory carrier? 

A person who can transmit the disease before showing any symptoms 

400

What is an active primary prevention? 

Type of prevention that requires individual behavior change, such as exercising or quitting smoking 

500

What is sporadic?

A disease that occurs occasionally and irregularly

500

What is vehicle-borne transmission?

Transmission through contaminated food or water

500

What is a susceptible host?

A host that is vulnerable to becoming infected by infectious agents 

500

What is a suspect case? 

A person whose signs and symptoms are consistent with a disease but has not yet been confirmed by lab tests

500

What is rehabilitation? 

The process of restoring health and functional ability after an illness or injury