A virus that makes people more stupid
Scientists have discovered a virus that makes people more stupid.
The algae virus - called chlorovirus ATCV-1 - was previously only known to appear in green algae in freshwater lakes.
But scientists at Johns Hopkins Medical School and the University of Nebraska made the surprise find of the algae in the throats of 44 per cent of the people they were testing in an unrelated experiment, the Independent reported.
It was found to infect the human brain and then affect cognitive functions, including visual processing and spatial awareness.
Dr Robert Yolken, a virologist who led the original study, said the finding showed how seemingly harmless organisms could actually change how people behaved.
"This is a striking example showing that the 'innocuous' microorganisms we carry can affect behaviour and cognition.
"Many physiological differences between person A and person B are encoded in the set of genes each inherits from parents, yet some of these differences are fuelled by the various microorganisms we harbour and the way they interact with our genes."
There were 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. Human bodies contain trillions of bacteria, viruses and fungi.
Most are harmless, but the findings of this research show there were some microbes that can have a detrimental impact on cognitive functions, while leaving individuals healthy.
The researchers then tested the virus on mice and confirmed the effects it caused,
The virus broke through the barrier between blood and tissue, altering the activity of genes in the brains of the mice.
In a human context, this means that at this early stage of discovery of the algae, people who have it in their system will not be able to get rid of it because it will have already altered the activity of their genes.
The study's findings were published in the Proceedings of the National Academy of Sciences.