contagious disease
noun
plural contagious diseases
: an infectious disease (such as influenza, measles, or tuberculosis) that is transmitted by contact with an infected individual or infected bodily discharges or fluids (such as respiratory droplets), by contact with a contaminated surface or object, or by ingestion of contaminated food or water
Note: The terms contagious disease and communicable disease are often used interchangeably. However, communicable diseases such as malaria or schistosomiasis that are spread by contact with disease vectors (such as mosquitoes or ticks) are not typically considered to be "contagious" diseases since they cannot be spread from direct contact with another person.
Examples of contagious disease in a Sentence
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Measles is among the most contagious diseases in the world, and case counts in the United States are spiking with more than 1,000 reported in 2025.
—
Cindy Krischer Goodman, Sun Sentinel, 27 May 2025
Rather, his ideas were treated like contagious diseases.
—Daniel Immerwahr, New Yorker, 19 May 2025
The measles vaccine was introduced in 1963, which marked a turning point for the contagious disease, which used to kill thousands every year.
—Joe Murphy, NBC news, 8 May 2025
Read more Tuberculosis, the world’s deadliest disease, could be America’s next outbreak
Earlier this month, a high school student in Joliet, Ill. tested positive for a highly contagious disease that has claimed more lives than any other throughout human history.
—Rachel Frazin, The Hill, 30 Apr. 2025
See All Example Sentences for contagious disease
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Cindy Krischer Goodman, Sun Sentinel, 27 May 2025
Rather, his ideas were treated like contagious diseases.
—Daniel Immerwahr, New Yorker, 19 May 2025
The measles vaccine was introduced in 1963, which marked a turning point for the contagious disease, which used to kill thousands every year.
—Joe Murphy, NBC news, 8 May 2025
Read more Tuberculosis, the world’s deadliest disease, could be America’s next outbreak
Earlier this month, a high school student in Joliet, Ill. tested positive for a highly contagious disease that has claimed more lives than any other throughout human history.
—Rachel Frazin, The Hill, 30 Apr. 2025
See All Example Sentences for contagious disease
Cite this Entry
“Contagious disease.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/contagious%20disease. Accessed 8 Jun. 2025.
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