Is a giant virus making us stupid?

[D]iminished cognitive functioning has generally been considered a consequence of either genetic inheritance or environmental pressure, but researchers at Johns Hopkins and the University of Nebraska-Lincoln (UNL) have discovered something that everyone else had missed: a virus.

While conducting a study on cognition, the scientists put volunteers through cognitive tests in addition to taking swabs of every participant’s throat. Surprise surprise:

Once subjects completed the original study’s cognitive assessments, the researchers also discovered that those participants carrying DNA of the chlorovirus — Acanthocystis turfacea chlorella virus 1, or ATCV-1 — performed measurably worse than those without it on tests of visual processing and spatial orientation.

ATCV-1 is a very large virus, containing about 400 genes, which makes it a monster when compared to most viruses with 7-10 genes. In fact, scientists have probably missed it because filters used to select for viruses contain pores that would be smaller than ATCV-1, meaning the chlorovirus was ‘caught in the filter’ each time.

The study demonstrates how pathogens can affect not only our health but our ability to think and remember. The big question now is how did a virus found heretofore only in algae jump kingdoms to populate in the throats of human beings? No, swimmers and non-swimmers alike have the virus, so being in water may not be the answer—unless it can be spread via oral contact. Think of that next time you kiss someone…

Read the entire report via UNL, Johns Hopkins researchers identify DNA of algae virus in humans | News Releases | University of Nebraska-Lincoln.