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Contagious vs Infectious
Difference, Examples & Quiz

What's the difference? Which one is correct?


Definition: Capable of being transmitted from one person or organism to another.

Usage: Contagious diseases can spread rapidly through a population.

Example sentences:
  • 1. The flu is highly contagious and can easily be passed from person to person.
  • 2. Measles is a contagious disease that can be prevented through vaccination.
  • 3. COVID-19 is a contagious respiratory illness caused by the novel coronavirus.

Definition: Capable of causing infection, especially by the invasion of microorganisms.

Usage: Infectious diseases are caused by pathogens such as bacteria, viruses, or fungi.

Example sentences:
  • 1. HIV is an infectious disease that attacks the immune system.
  • 2. Tuberculosis is an infectious bacterial disease that primarily affects the lungs.
  • 3. Malaria is an infectious disease transmitted through the bite of infected mosquitoes.

The differences between 'Contagious' and 'Infectious' are as follows: 'Contagious' refers to the ability of a disease or infection to spread from one person to another through direct or indirect contact, while 'Infectious' refers to the ability of a pathogen or microorganism to invade and multiply within a host organism. While both terms are related to the transmission of diseases, 'Contagious' specifically emphasizes the ease of transmission, whereas 'Infectious' focuses on the ability to cause infection.

Quizzes about "Contagious" vs "Infectious"

Contagious vs Infectious: 5 Quizzes

1. What is the definition of contagious?

2. Which of the following is an example of a contagious disease?

3. What is the difference between contagious and infectious?

4. What is an example of an infectious disease that is not contagious?

5. Why is it important to understand the difference between contagious and infectious?


  • What does contagious mean?

    Contagious refers to the ability of a disease or infection to spread from one person to another through direct or indirect contact.

  • What does infectious mean?

    Infectious refers to the ability of a disease or agent to enter, establish itself, and multiply in a host, leading to infection and potential transmission to others.

  • How do contagious diseases spread?

    Contagious diseases can spread through various means, including respiratory droplets, physical contact, contaminated surfaces, or vectors like insects.

  • What are some examples of contagious diseases?

    Examples of contagious diseases include the common cold, influenza, chickenpox, measles, tuberculosis, and COVID-19.

  • How can infectious diseases be prevented?

    Prevention of infectious diseases involves measures such as vaccination, practicing good hygiene, maintaining a clean environment, and following appropriate infection control protocols.