Infectious-Contagious | Commonly Confused Words
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Infectious vs. Contagious

Infectious

/ɪnˈfekʃəs/
Causing or capable of causing infection by spreading pathogens.

Examples:

Laughter is infectious, spreading smiles across the room.The enthusiasm of the team was totally infectious.Her creativity is infectious, inspiring everyone around her.

Synonyms:

Antonyms:

Contagious

/kənˈteɪdʒəs/
Able to spread from one person or organism to another by direct or indirect contact

Examples:

Her enthusiasm for the project was contagious.Laughter can often be surprisingly contagious.Yawns are known to be incredibly contagious.

Synonyms:

Antonyms:

This word has no antonyms

Ways to tell them apart:

etymology
  • Infectious often relates to the nature of a disease and its ability to enter and multiply in a host or spread, whereas contagious focuses more on the ease with which a disease is passed from person to person.
  • Contagious diseases require direct or indirect contact to spread, like touching or breathing the same air, while infectious encompasses a broader range, including those transmitted through vectors like mosquitoes.
  • To remember: All contagious diseases are infectious, but not all infectious diseases are contagious.
  • Infectious can also encompass non-contagious diseases, like food poisoning or tetanus, which are contracted but not passed from person to person.
  • Contagious is more about the social aspect of disease spread, i.e., how one should act to prevent passing the disease to others.
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