The lowly maggot gets a bad rap, mostly known for feeding on corpses and rotting meat.

But modern medicine is giving its reputation new life — as a tiny surgeon.

Polly Cleveland, of New York City, turned to so-called maggot therapy when she was caring for her late husband, Tom, in 2023.

“After a stay in the hospital, he came back with this terrible sore on his left heel,” Cleveland said. Later, he developed a bedsore on his buttocks. “These kinds of wounds really smell foul.”

The doctors and nurses treating her husband had never heard of using maggots for wound cleaning. Cleveland, who has a lifelong interest in bugs, found a lab established by Dr. Ronald Sherman, a pioneer of modern maggot therapy, and was able to order a shipment of maggots overnight.

Medicinal maggots are considered FDA-cleared medical devices, which are specially raised in laboratories to be germ-free. Maggots are the larvae of flies.

“You get this little vial with these teeny, tiny little maggots on a piece of gauze,” Cleveland said. (The maggots can also be sold in a sachet resembling a tea bag, so they can’t wander freely.) “I stuck the maggots in, and by golly, they did their thing.”

The wounds, she said, had been “so icky,” with “pus and other nasty stuff coming out of them.” Once the maggots were finished, “it was sort of a dimpled, pink tissue, really nicely cleaned up.”

Flesh is food

The thinking behind maggot therapy is straightforward: Diseased and dying tissue must be removed from wounds in order to prevent infection. To maggots, this dead tissue is food.

Using maggots is painless. “The maggots remove dead tissue by dissolving it,” said Sherman, a retired assistant professor of medicine at the University of California, Irvine, who is now the medical and scientific director at Cuprina, a biotech company that sells medicinal maggots. “They do not have teeth. They do not bite pieces from the tissue. They secrete their digestive enzymes which dissolve the dead infected tissue in the wound, and so only that tissue melts away. The healthy tissue stays behind.”

In severe cases, so-called wound debridement is done surgically.

“Surgery tends to be a bit coarse,” Sherman said. “The scalpel is straight, and the border between healthy tissue and dead tissue is not straight. The surgeon’s vision is limited to a macroscopic level, not a cellular level, not a microscopic level.”

That’s not a problem for maggots, which can remove dead flesh with a degree of precision surgeons can’t achieve.

Maggot therapy can be used in people who might not do well in surgery.

“You don’t need anesthesia, which is the greatest risk for people who are deemed poor surgical candidates,” Sherman said.

Lisa Baxter, the clinical director of the inpatient wound and ostomy care team at Tufts Medical Center in Boston, said her team uses maggot therapy once or twice a year, usually for patients who can’t have surgery.

“We’ve had a couple patients awaiting heart transplant that had wounds that needed to be healed before they could get their transplant, so this is sort of a simple way to expedite the process,” Baxter said.

She added that, curiously, maggots don’t like the bacteria Pseudomonas, a common cause of infection in hospitals. If using maggot therapy, she said, “We have to make sure that the wound does not have Pseudomonas in it.”

Dr. David Armstrong, the director of the University of Southern California Limb Preservation Program, turned to maggots during the pandemic.

He recalled one of his patients whose surgery for a gangrenous foot wound had been canceled because of Covid. The patient had heart failure, diabetes and peripheral artery disease.

“His feet were going to kill him,” Armstrong said. To forestall further infection, he recommended home maggot therapy. Nurses, with maggots on hand, visited the patient at home and Armstrong guided the process over a video call. He said the approach saved the man from losing more of his foot.

The ick factor

If maggots can be so beneficial, why aren’t they used more frequently?

For one, there’s the issue of insurance. “Maggot therapy is not adequately reimbursed by our system of medicine,” Sherman said.

Sherman said maggots are cheaper than a type of ointment commonly used to clean wounds, called an enzymatic debrider. “You can probably buy enough maggots to treat one or two wounds for $400,” he said. The ointment, which is covered by insurance, costs around $450 for a week’s supply and can take more than 12 weeks to fully clean a wound.

Not everyone sees a use for maggot therapy.

Dr. Sameer Patel, chief of plastic and reconstructive surgery at Temple University Hospital and Fox Chase Cancer Center in Philadelphia, said there are already plenty of options available for wound management.

“This is not what one would consider by any means standard of care,” Patel said. “The case reports and the things that we see in the literature [on maggot therapy] are very unique situations.”

He said there isn’t enough high-quality data to support wider use of maggot therapy. “Do I think it’s ever going to become a widespread modality? No, I don’t think that’ll happen,” he said.

Then, of course, there is the “yuck factor.”

Sherman said that he’s “been seeing patients who would get a prescription for the maggots, but the doctor wouldn’t do it. In those cases, it’s usually because they’re maybe grossed out by it.”

Larry Way, 71, of Malden, Massachusetts, got over the grossness after he was hospitalized at Tufts Medical Center for a severely infected wound in 2021.

“He failed anything that we tried and was quite ill, and was actually probably going to go to hospice and die within a couple of weeks because we couldn’t fix this wound,” said Baxter, who treated Way.

“We’ve tried A, B, C, D, E,” she said. “The only thing that’s left is maggots.”

Way said that although he was “maybe a little concerned,” he decided that it was worth braving the ick factor to try to save his life. It worked.

The treatment, he said, was painless.