Maggots: Thumbs Up or Down?
The weather is starting to heat up here in Colorado, which means that any day now I’ll see my first case of maggots for the year. I hate dealing with maggots. I could come up with all sorts of profound reasons why, but the truth of the matter is they are just gross.
Today I’m going to try to overcome my bias against fly larvae and discuss the good that maggots can do in a medical setting — specifically maggot debridement therapy.
Maggots have been used for hundreds of years to aid in wound healing. They can clean up and stimulate the healing of dirty, infected wounds that are not responding to other therapies. Modern treatment involves what are known as medical-grade maggots (I love that term. I can’t help but picture maggots in white lab coats with stethoscopes around their "necks"). These are a specific species of maggot (Lucilia sericata, or the common green bottle fly or blowfly) that very selectively break down and eat only unhealthy tissues. Other maggots are not so discerning in their tastes and can therefore do more harm than good.
Medical-grade maggots are purchased from a licensed laboratory where the fly eggs are disinfected and hatched in a sterile container. That is where they undergo their first few molts, growing to be between one and one and one-half centimeters long. They are shipped to clinics in sterile, temperature controlled containers and should be used within a day or two of their arrival.
Wounds must be surgically debrided (i.e., as much dead tissue and debris is removed as possible) and cleaned before the maggots are put in place. Antiseptics and other products that could adversely affect the maggots’ well-being should not be used within the wound. Once the maggots are in place, the area is covered with materials that keep the maggots from wandering away, allow air to flow to and from the wound (maggots gotta breathe, you know), and absorb the large amount of fluid that maggots generate. These bandages need to be changed at least twice a day to prevent moisture from damaging the surrounding tissues.
Maggots are generally removed after a couple of days (longer than this and they tend to want to escape and head for greener pastures) at which time the wound is reassessed. Sometimes, multiple applications of maggots are necessary before the area is clean enough and has developed enough granulation tissue to heal on its own, or to be a good candidate for surgical repair.
I hear that maggot therapy is not painful, so analgesics are only necessary if the initial wound requires such intervention.
What do you think? Are maggots cool? My brain may accept that they can be beneficial, but I have to confess that my subconscious still isn’t on board. Those little buggers still give me the heebie-jeebies.
Dr. Jennifer Coates
Image: Dr. Maggot