BOULDER, Colorado — There’s not much appeal, if any at all, to coming down with a parasitic infection. But would you believe that one such condition could actually play a role in your career choice?

A recent study found that an infection by the cat-borne parasite Toxoplasma gondii may increase an individual’s likelihood of engaging in business-related or entrepreneurial activities.

According to previous research, 2 billion people worldwide are infected with T. gondii, which causes the disease toxoplasmosis, and has been shown to increase impulsive behaviors, along with the risk of car accidents, road rage, mental illness, neuroses, suicide, and drug abuse. According to the CDC, more than 40 million people in the U.S. may be infected with the parasite.

Researchers from the University of Colorado in Boulder tested 1,495 undergraduate students and found that those infected with T. gondii were 1.4 times more likely to major in business and 1.7 times more likely to enter a management or entrepreneurial emphasis. The researchers also conducted a survey of 197 professionals attending entrepreneurship events and found that those infected were 1.8 times more likely to have started their own business than other attendees.

The authors also took their research global, compiling national statistics from 42 countries around the world. The infection rate in the countries analyzed ranged from nine percent in Norway to 60 percent in Brazil. The researchers found that a T. gondii infection was a consistent, positive predictor of entrepreneurial activities, even when controlling for national wealth and opportunity.

“As humans, we like to think that we are in control of our actions,” says co-lead study author Pieter Johnson, professor in CU’s Department of Ecology and Evolutionary Biology, in a statement. “But emerging research shows that the microorganisms we encounter in our daily lives have the potential to influence their hosts in significant ways.”

Economic research often hinges on analyzing which decisions people make are logical, based on them weighing the benefits and drawbacks of a business action. But T. gondii might steer some people into making more high-risk, high-reward decisions than they otherwise would.

The study also found that higher infection rates strongly correlated with fewer subjects responding with “fear of failure” as the reason they didn’t pursue a new business venture. It could be because the parasite lessens the natural concern of a new business opportunity failing since a high percentage struggle to succeed.

“Infectious diseases have strongly shaped human history and culture over millions of years,” says Johnson. “Today, we like to believe our decisions and destiny are ours alone, but the contributing roles of our microscopic companions are increasingly apparent.”

The authors say that the study did not show whether or not business ventures started by those infected with the parasite were more likely to succeed or fail.

The study was published in the journal Proceedings of the Royal Society B.

About Ben Renner

Writer, editor, curator, and social media manager based in Denver, Colorado. View my writing at

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