The Conversation

You’ve possibly heard of parasites that can swim through your blood, chew through your intestines and lay eggs in pretty much every scrumptious organ in your body.

Well, here’s another one to add to your microbial fun house of horrors: parasites that decapitate sperm.

Bill Sullivan, a microbiologist at Indiana University, runs a lab that studies Toxoplasma gondii. He’s well acquainted with the various eyebrow-raising quirks and talents of this parasite, such as its ability to change your personality and behavior; cause miscarriage, birth defects or even death; and establish a lifelong infection. It’s squatting in the bodies of about 30% to 50% of the world’s population.

When he came across a study on how Toxoplasma can directly damage sperm – by beheading them, drilling holes in them, or otherwise twisting them into submission – even his eyebrows were raised. The researchers who authored the study speculated that this parasite might be contributing to declining male fertility rates worldwide.

You can catch Toxoplasma through cat feces, raw meat and raw shellfish, and fruits and vegetables that aren’t well washed. Sullivan explains how the latest study adds to the bad rap of this parasite and what people can do to evade infection.

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Toxoplasma can infiltrate the reproductive system. wildpixel/iStock via Getty Images Plus

A common parasite can decapitate human sperm − with implications for male fertility

Bill Sullivan, Indiana University

If you’ve handled cat litter or eaten raw meat or unwashed produce, there’s a chance you might have a permanent toxoplasmosis infection spread throughout your body.
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