There is no shortage of hospital workers in and around Greater Boston, and seeing them about town got Jamaica Plain listener Mia Snow to wondering.

"Why do healthcare professionals wear scrubs outside of the workplace? I've seen people in scrubs walking down the street, on the subway, in coffee shops. Whether they're going to work or coming home, it just seems to me that people should not be bringing germs in or taking them out of the hospital."

Whether we realize it or not, we all spend a lot of time with germs. Right now, there are germs on our bodies, on our clothes, and all around us. But few of us spend as much time thinking about germs as Dr. David Hooper, chief of Massachusetts General Hospital’s Infection Control unit.

"The bugs are clever," Hooper said. "So we never can let our guard down, declare victory, and go home."

So what — if any — role do the scrubs Mia sees all over play in the battle against germs in hospitals? Actually, not a big one. For starters, Hooper points out that just because you see a person in scrubs, it doesn’t mean they work in a hospital. And even if they do, they might not have any interactions with patients.

"Many hospital personnel find them just very convenient working garb," he explained. "Uniforms of sorts."

In areas where germs are of particular concern, like operating rooms, scrubs certainly are worn. But they’re not the ones you see folks walking around in outside the hospital.

"We provide, in fact, for O.R. personnel — scrubs," said Hooper. "Then there’s a changing room where people then change into their scrubs."

These scrubs are laundered at higher temperatures and with disinfectants, ensuring a level of cleanliness beyond what would be achieved at home. And there are even further safeguards in place for interactions with patients with certain communicable viruses or antibiotic-resistant bacteria.

"We have healthcare workers don disposable gowns and gloves," said Hooper. "There’s a specific sequence for putting them on and taking them off, and then after patient encounter, they are removed."

Hooper said that policies like these and others that promote safety around higher risk interactions like contact with body fluids, catheters, and IVs are common across hospitals. So, in the end, does he worry about rogue germs hopping a ride into the hospital on healthcare workers' scrubs and infecting patients?

"No, I would say that’s generally a very low-risk circumstance," Hooper said.

How about germs making their way out into the wider world when workers go on a shift break or head home?

"The risk of the public getting something from somebody being out in the community from scrubs is exquisitely low," he said.

Of more concern is the spread of germs from one patient to another inside the hospital. What role might scrubs play here?

"We know that clothes can be contaminated, but we’re really struggling to figure out how much of an impact it really has in the transmission of infections or organisms within a hospital," said Dr. Dev Anderson, an infectious disease physician at Duke University.

Notice that Anderson said "clothes." Scrubs are comfortable and easy to launder, but they are no more germ-resistant than any other clothing. Anderson has run studies on nurses that show germs can accumulate on their scrubs over the course of a shift, though not at dangerous levels.

But what if the germs couldn't attach to clothing at all?

"We’d sure like to find something like that, just because it seems like a good idea," Anderson said. "But we haven’t really found it."

There are, however, companies working on it. There are “next gen” scrubs on the market that include things like copper and silver threading, or embedded antiseptics. But Anderson said they’ve yet to prove significantly more germ-resistant than regular scrubs. And even if technology could produce a completely sterile set of scrubs, Mass General’s Dr. Hooper said there is a far greater issue at hand: Health care worker’s hands.

"That’s where the action is — literally and figuratively, in this case," he said.

Skin is a far more hospitable environment for most germs than any clothing. So while it might not be sexy, Hooper said that the front line of defense against those nefarious bugs is... good old-fashioned hand washing.

"We emphasize the concept of hand hygiene before and after every patient contact," he said. "We think it’s extremely important."

So, it turns out, when it comes to health care workers and fighting the spread of infection, it’s not so much the scrubs they are wearing as it is the scrubbing they are doing.

My thanks to Mia Snow of Jamaica Plain for her question that led to this story. What's yours? Let us know what has piqued your curiosity lately at curiositydesk@wgbh.org.