in·​fect·​ed in-ˈfek-təd How to pronounce infected (audio)
: having an infection : contaminated with an infective agent (such as a bacterium or virus)
an infected wound
Through a number of different means, these viruses persist at very low, hard-to-detect levels in infected cells.The Journal of the American Medical Association
She explains that leptospirosis bacteria are shed in the urine of infected animals.Tania Banak
The fungus produces as many as 1 million conidia per square centimeter of infected leaf surface.G. B. Lucas

Examples of infected in a Sentence

Recent Examples on the Web Animals can also become infected if their feed or pasture is contaminated with the prions carrying it. Li Cohen, CBS News, 17 Nov. 2023 Many people who become infected with the bacteria never develop symptomatic tuberculosis. Aria Bendix, NBC News, 10 Nov. 2023 Risk factors for constipation might already exist in an infected person, so pinpointing the exact reason for it is challenging. Korin Miller, Health, 31 Oct. 2023 When an infected or recently sick swimmer takes a dip, oocysts can enter the pool. Beth Mole, Ars Technica, 26 Oct. 2023 Dengue fever is a viral infection spread to humans by the bites of infected mosquitoes, primarily Aedes aegypti. Will Sullivan, Smithsonian Magazine, 26 Oct. 2023 The transmission of these bacteria often occurs through close contact with an infected individual via activities like sneezing, coughing, or contact with an open wound. Sandra Rose Salathe, Peoplemag, 12 Sep. 2023 About 1 in 5 people who are infected develop a fever, and about 1 out of 150 infected people develop a serious illness, but many never even feel sick, according to the CDC. Ovetta Wiggins, Washington Post, 5 Oct. 2023 Only five percent of people who are exposed actually become infected, because most people’s immune systems are able to brush these bacteria off. Rachel Feltman, Popular Science, 11 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'infected.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


from past participle of infect

First Known Use

1534, in the meaning defined above

Time Traveler
The first known use of infected was in 1534

Dictionary Entries Near infected

Cite this Entry

“Infected.” Dictionary, Merriam-Webster, Accessed 2 Dec. 2023.

Last Updated: - Updated example sentences
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