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 eventually discovered to be avian flu caused by the H5N1 virus.

From Salon • Jan. 13, 2025

The viral load in placentas and fetuses was significantly lower in the vaccinated group versus the unvaccinated group.

From Science Daily • Mar. 4, 2024

In 1996, Terrill’s doctor informed him that his viral load was so low it was undetectable.

From Los Angeles Times • Feb. 14, 2024

The vast majority were taking antiretroviral therapy and had an undetectable viral load.

From BBC • Oct. 16, 2023