Imagine that a thousand people—randomly selected from the U.S. population—had unprotected sex yesterday. How many of them will eventually die from contracting HIV from that single sexual encounter?
Now, imagine a different thousand people. These people will drive from Detroit to Chicago tomorrow—about 300 miles. How many will die on the trip as a result of a car crash?…
If you’re anything like the participants in a new study led by Terri D. Conley of the University of Michigan, the HIV estimate should be bigger—a lot bigger. In fact, the average guess for the HIV case was a little over 71 people per thousand, while the average guess for the car-crash scenario was about 4 people per thousand.
In other words, participants thought that you are roughly 17 times more likely to die from HIV contracted from a single unprotected sexual encounter than you are to die from a car crash on a 300-mile trip.
But here’s the deal: Those estimates aren’t just wrong, they’re completely backward.
According to statistics from the U.S. Centers for Disease Control and Prevention and the United States National Highway Traffic Safety Administration, you are actually 20 times more likely to die from the car trip than from HIV contracted during an act of unprotected sex.
While the rest of this article goes on to talk about perceptions of sex in the United States, these findings are consistent with others that suggest Americans don’t see driving as a threat to their safety. Driving is one of the riskier behaviors Americans regularly engage in: more than 30,000 Americans are killed each year in vehicle accidents. (It should be noted that this figure has dropped from the low 50,000s from the late 1960s and early 1970s. Driving today is safer than in the past.) Yet, Americans tend to like driving (or at least what it enables) and find it necessary in their daily lives (by social and political choices we have made) so those deaths and car accidents are acceptable losses.
Of course, it may not be long before even having to acknowledge our difficulties in weighing risks is no longer a problem due to driverless cars that eliminate all vehicle deaths.