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viruses

  • plural
    of virus.
    virus
    noun
    an ultramicroscopic (20 to 300 nanometers in diameter), metabolically inert, infectious agent that replicates only within the cells of living hosts, mainly bacteria, plants, and animals: composed of an RNA or DNA core, a protein coat, and, in more complex types, a surrounding envelope.

Example Sentences

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Under Kennedy, the U.S. government also canceled Moderna’s contract to develop mRNA-based vaccines for pandemic influenza viruses.

From The Wall Street Journal ● Aug. 22, 2026

Those immune targets included common viruses and bacteria, along with targets connected to autoimmune diseases.

From Science Daily ● Aug. 21, 2026

The results show that dormant viruses can reactivate frequently in people who appear to have functioning immune systems during severe illness, particularly when systemic inflammation is elevated.

From Science Daily ● Aug. 16, 2026

On Thursday, scientists announced that they’d used generative AI to create a new family of viruses.

From The Wall Street Journal ● Aug. 9, 2026

They didn't realize that airborne viruses and bacteria led to pneumonia, measles, and smallpox among soldiers living in crowded conditions.

From "Ambushed!" by Gail Jarrow