The Return of the Puppet Masters
In a post from a few years ago titled, Do you love cats?, I wrote this:
Toxoplasma gondii is a favorite parasite of evolutionary biologists because it has an incredible property. The parasite lives in the guts of cats where it sheds eggs in cat feces that are often eaten by rats. Now how to get back from the rat to the cat? Amazingly, Toxoplasma gondii infects the brains of rats making them change their behavior in a subtle way that increases the genetic fitness of the parasite. Toxoplasma makes the infected rats less scared of cats and so more likely to be eaten!
Now here is the kicker. Toxoplasma gondii also infects a lot of humans.
Now here is the latest research finding;
Toxoplasma gondii infects 20–60% of the population in most countries...We confirmed, using for the first time a prospective cohort study design, increased risk of traffic accidents in Toxoplasma-infected subjects...Our results show that ...subjects with high titers of anti-Toxoplasma antibodies had a probability of a traffic accident of about 16.7%, i.e. a more than six times higher rate than Toxoplasma-free... subjects.
People with RhD blood factor have some protection - see the article for more. No word yet on whether this increases the probability of being eaten by cats although I suppose it would have to.