A dynamic germ-fighting duo is helping people who live on the streets win the battle of recovering from wounds, illnesses and hospitalizations with the efficacy and empathy of having been there themselves.

Because they have.

“I’ve got one word for them — phenomenal,” growled John Burchfield, a former Marine who said he went “a little crazy” when his wife died three years ago and spiraled into homelessness.

“They’re kick-a–,” he said with admiration, after Greg Morris and Codi Natelli got done with him last Wednesday.

Morris, a physician assistant, and Natelli, an emergency medical technician, tended to an angry-looking red strip on Burchfield’s forearm where doctors had done surgery a few weeks ago.

It’s easy for bodies not to mend like they should when they spend their days and nights outside and are subjected to malnutrition, substance use and temperature extremes.

“Being on the street ages you in dog years,” Natelli said, apologizing for the analogy.

But it’s the best one she knows to describe how fast the harsh living conditions take a toll on human bodies. Dogs age at an accelerated rate compared to humans, according to the American Kennel Club. Depending on its size, a 10-year-old dog is equivalent to a human’s age of 56 to 79 years old.

“We’re seeing advanced-age diseases in their 30s, 40s and 50s that we would usually see in people in their 70s and 80s,” she said. “Most (street people) don’t live that long.”

It’s not uncommon for chronically homeless people — those who have a mental or physical disability and have been without stable housing for one year or more — to develop serious conditions like chronic obstructive pulmonary disease or congestive heart failure in their mid-30s, Natelli said.

Morris and Natelli work hard to extend the expected shortened life span.