In 2004, the U.S. Food and Drug Administration (FDA) approved medical-grade maggots as a “medical device” to debride chronic or non-healing wounds. It gave Sherman’s maggots a level of legitimacy he needed to treat patients on a wider scale. It also meant that he needed to raise his maggots in a dedicated lab to create a better-quality product and stay within FDA guidelines. So in 2007, he founded Monarch Labs, the first modern American company devoted solely to the production of sterile therapeutic maggots.
In Europe, a competing company, BioMonde, was also gaining momentum. They used the same blowfly species, but they hoped that their 2005 invention of the BioBag would set them apart. Instead of selling their maggots loose, like Monarch Labs and others, BioMonde sold theirs in a white silk mesh bag that, to an outsider, looks like a large teabag containing miniature grains of rice.
“You don’t have to see the maggots, you don’t have to touch the maggots. Everything is contained in the bag. And when you’re done, you just pitch it and place a new bag on,” says Katy Nicell, a product manager at BioMonde’s new office in Gainesville, Florida.
Sherman maintains that loose larvae do a better job than the bagged ones, since their movement across the wound surface helps to remove dead cells. “The maggots are a little lumpy-bumpy on the outside, and as they crawl across the wound, they’re acting like a file, similar to how a toothbrush cleans teeth. The physical action is important—you don’t just use mouthwash on your teeth,” he says.
But the BioBag was perfect for Linda Cowan, a nurse investigator at the Malcom Randall Veterans Affairs Hospital in Gainesville. She wanted to start a trial of maggot therapy and the bagged larvae were just more convenient for patients and their caregivers. With loose larvae, you have to count them as you place them on the wound, and count them again as they’re removed, as part of a technique Cowan wryly refers to as “no maggot left behind.”
“The problem with that is when you put in 100 maggots, that’s a big, time-consuming thing,” she says. “And then if you bring out 90 maggots, there’s a huge concern, you can see on the face of the patient, where did the other 10 go? Did they climb in my ears at night? Did they escape? Where did they go?”
A bag avoids any such concerns. It’s also a bonus for patients in hospitals, where many physicians are reluctant to allow loose maggots into their facilities.
Whether you take your maggots loose or in a bag, they work on unhealed wound tissue in the same way. Although maggots do have a mouth, they don’t munch directly on a wound. Instead, enzymes in their saliva start to break down the bacteria and dead cells, a process called extracorporeal digestion. Laboratory studies have shown that these enzymes help to kill bacteria and also increase the production of immune-system chemicals that help the body fight infection and heal wounds. Once the cells have dissolved into a nutritious smoothie, the maggots slurp it up.