Stupidity Virus Discovered

Apparently, it strikes journalists preferentially, if this article is any indication: Virus that 'makes humans more stupid' discovered

A virus that infects human brains and makes us more stupid has been discovered, according to scientists in the US.

The algae virus, never before observed in healthy people, was found to affect cognitive functions including visual processing and spatial awareness.

Scientists at Johns Hopkins Medical School and the University of Nebraska stumbled upon the discovery when they were undertaking an unrelated study into throat microbes.
Surprisingly, the researchers found DNA in the throats of healthy individuals that matched the DNA of a virus known to infect green algae.

The creature from the Green Lagoon!

Dr Robert Yolken, a virologist who led the original study, said: “This is a striking example showing that the ‘innocuous’ microorganisms we carry can affect behaviour and cognition.
. . .
Of the 90 participants in the study, 40 tested positive for the algae virus. Those who tested positive performed worse on tests designed to measure the speed and accuracy of visual processing. They also achieved lower scores in tasks designed to measure attention.
. . .
The study’s findings were published in the Proceedings of the National Academy of Sciences.

So they examined 90 people, and 40 tested positive for the virus, and these were, on average, a little dimmer than those without the virus?

The first answer to that is that correlation is does not imply causation. There are lot's of reasons that out of a group of 90 people, one trait may correlate with another for an a reason that has nothing to do with causation. Maybe the positive people were more likely to have been stupid and poor and drink contaminated water containing the green algae hosts.

Second, a sample size of 90 is wholly inadequate for a study with these implications.

I can't believe the PANS published this crap. But I can see how reporters picked it up.