The microscopic parasite Toxoplasma gondii affects sperm quality and has been linked to the global 80 percent rise in male infertility between 1990 and 2019. The parasite is known to directly damage human sperm by decapitating them and indirectly by inducing chronic inflammation.
A significant number of people are permanently infected with T. gondii, mainly through contact with contaminated food or infected animal waste, and the parasite can potentially remain in the body for life.
Bill Sullivan, professor of microbiology and immunology from Indiana University, writes more in The Conversation.