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One Drop Of Blood Can Reveal Almost Every Virus A Person Has Ever Had

A new experimental test called VirScan analyzes antibodies that the body has made in response to previous viruses. And, it can detect 1,000 strains of viruses from 206 species.

ByAllison EckNOVA NextNOVA Next
A very small amount of blood could betray a person's entire history of viral infection.

A single drop of blood may contain nearly all the information you need to know about a person’s viral past.

The new experimental test, called VirScan, opens up a world of possibilities, so much so that its development has been compared to the advent of the electron microscope. Able to detect 1,000 strains of viruses from 206 species, the test analyzes antibodies that the body has made in response to previous viruses.

The result is a nearly comprehensive record of the human “virome,” and it could eventually give researchers insight into whether or not viruses contribute to chronic diseases and cancer. In other words, scientists may find out what viruses antagonize the immune system by creating antibodies that subvert it—or, they could discover why chemotherapy works well for some people but not for others.

Stephen J. Elledge, senior author of the report published in Science, and his team administered the test to 569 people in the United States, South Africa, Thailand, and Peru. The VirScan results indicated that most people tested had been exposed to about 10 different species of virus, though others had been exposed to as many as 25. People outside the United States had higher rates of exposure, which could be due to a number of factors: sanitation levels, genetic variation, population density, and so on. In the long term, more thorough comparisons between countries’ viral histories could lead to better epidemiological practices across the globe.

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The test can take up to two months to perform right now, but if a company were to acquire it, the whole process may be completed in as few as two or three days, Elledge told The New York Times. And with expedited testing, scientists could study everything from the age at which children acquire various illnesses to how disease has changed throughout history. They may even encounter some unexpected results—in fact, they already have.

Here’s Denise Grady, writing for The New York Times:

The initial study had some surprises, Dr. Elledge said. One was “that the immune response is so similar from person to person.” Different people made very similar antibodies that targeted the same region on a virus, he explained.

Another surprise came from people infected with H.I.V. Dr. Elledge expected their immune responses to other viruses to be diminished. “Instead, they have exaggerated responses to almost every virus,” he said. The researchers do not know why.

The test has some limitations, but this is certainly a major step forward in scientists’ goal to track the progress and potency of illness and disease all over the world.

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