With so many antibiotic-resistant bacterial strains floating around hospitals, why do I see so many hospital and nursing home workers in their scrubs commuting on TriMet? What do their infection control officers think about this? —Antibiotic-Laced Chicken Little

Here's a vocabulary word sure to net you an irritated glare from your doctor: "iatrogenic," the adjective for illnesses or injuries caused by medical treatment.

This concept had its real heyday back when "medical treatment" meant a trip to the barber for a brisk round of bloodletting, but tenacious, hospital-acquired infections like the ones you describe are making it handy once again.

If it's any consolation, the American medical establishment seems to be getting a handle on the problem—hospital-acquired C. difficile infections, for example, dropped 13 percent between 2016 and 2017, according to the CDC.

There are still plenty of treatment-resistant superbugs around, but there are any number of reasons not to leap to the conclusion that anyone in scrubs is a walking MRSA bomb.

For starters, tons of people wear scrubs at work. The lady who photocopies insurance cards at my dentist's office wears them, for example. So does the guy who hands me my prescription at Walgreens—just because someone wears scrubs doesn't mean they spent the day wallowing in infected mucus.

And even if they did, the scrubs themselves should be clean! As Occupational Safety and Health Administration guidelines put it, scrubs "are usually worn in a manner similar to street clothing, and should be covered by appropriate gowns, aprons or laboratory coats when splashes to skin or clothes are reasonably anticipated."

What about OR scrubs? Gotta be some fluids on those, right? Well, as it turns out, OR scrubs are a totally different animal. They're designed differently, washed differently (and never at home), and only worn in the OR itself. (American College of Surgeons guidelines specifically forbid wearing OR garb outside the hospital perimeter.)

Having said all that, it is true that some studies have detected traces of pathogenic bacteria on nurses' scrubs. Of course, the same bacteria show up on nurses' street clothes as well. At least the ones in scrubs give you a clear focus for your paranoia.