viral load

American  

[vahy-ruhl lohd] / ˈvaɪ rəl ˈloʊd /

noun

Pathology.

1. the amount or concentration of a virus in a given quantity of blood, saliva, mucus, or other bodily fluid, often expressed as the number of viral particles per milliliter of the fluid: The droplets from a flu-infected person’s sneeze leave their viral load on whatever surface they land on.

   When HIV treatment is effective, the viral load in the blood becomes undetectable.

   The droplets from a flu-infected person’s sneeze leave their viral load on whatever surface they land on.

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viral load Scientific  

/ vī′rəl /

1. The concentration of a virus, such as HIV, in the blood.

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Etymology

Origin of viral load

First recorded in 1965–70

Example Sentences

The trial evaluated the regimen’s success in preventing HIV-1 replication using viral load, a measure of the amount of HIV genetic material in the blood.

From Barron's • Feb. 25, 2026

Further testing suggested she had a high viral load of a novel influenza A infection, which researchers discovered to be the H5N1 avian flu.

From Salon • Jan. 6, 2025

Three days later, viewed under a microscope, the nasal epithelial cells - as they are known - taken from children were quick to defend against the virus and reduce viral load.

From BBC • Apr. 15, 2024

But some people, known as "post-treatment controllers," have been able to discontinue their treatment while maintaining an undetectable viral load for several years.

From Science Daily • Jan. 23, 2024

The treatment is effective enough that you reduce your viral load so that an infection doesn’t show up on a test; then after treatment ends, your viral load increases again.

From Los Angeles Times • Mar. 24, 2023