Saturday, September 24, 2016

For Survivalists: Maggot Infestation of Wounds: Myiasis

               
Photo: atlantablackstar.com




                 Most people who have an interest in survival and emergency nursing believe that maggot infestation of wounds is a problem only in the Third World.  Most correctly, maggot infestation of wounds can occur absolutely anywhere in the world.   There are a wide variety of flies including Old World and New World screw worms which can cause a fatal infestation in animals and also in people.   A soldier, a homeless person, a traveling migrant, or anyone else who frequents the out of doors or a tent living situation, can develop a wound and have flies lay larva in it.  The larvae then hatch and the insects feed on moist necrotic tissue.
                 The first time I ever saw this was the time I rescued a turtle with an compression fracture of its shell.  Flies had laid larva in the compression fracture area before I had encountered it. Once the infestation was established, not even the vet could not save the poor creature.    On a farm we see this occasionally with elderly dying animals. especially those who are no longer able to swat flies or in those who are in in multi-system failure. Even though curing the issue might not save them in the long term, it will promote their comfort. Make no mistake, some animals and some humans can die from such infestations, even when whomever is treating them finally gets a handle on the primary cause for their health problem.Infection with fly larvae can be an important cause of mortality for some.

                  Occasionally, nursing homes are fined when maggots are detected in bedsores. This is the reason that restaurants as well as nursing homes often use a blue wall device which electrocutes flies.

                    There are some harrowing accounts of soldiers from the first world war who were caught in no man's land for several days with open fractures. By the time the men were retrieved, their wounds were filled with maggots.  Such men had a 75% chance of mortality when discovered in this manner.  The Civil War also had its share of deaths from this issue.

                       In later years physicians used sterile maggots bred in labs to clean wounds with large amounts of necrotic tissue, however these are specially bred and fairly innocuous  types and the entire process is watched very carefully.

                    Myiasis is the medical term for such infestations. It is pronounced as if written my-eye-a-sis.


There are a variety of different classes of infections of this type:

1. The first one is a nosocomial myiasis.   Nosocomial always means hospital acquired or acquired during the course of receiving medical care.  (An example of this would be the bedsore with myiasis encountered by the nursing home patient as I mentioned earlier.)    Hospitals take great steps to avoid flies for this reason.

2.  A cutaneous myiasis is also possible.   This is an infection of this kind within the skin. This is far more common in tropical regions, but it can occur almost anywhere in the world.
3. Infections of the eye, or Opthalmomyiasis can also occur.
4. Such infections may also occur in other body orifices, such as nose, ears and occasionally mouths. The urinary tract and the intestine may also be infected, particularly when someone ingested larva in food or drink.
5. In animals, injections of Ivermectin and Dectomax can be used to kill the invading agent.  Although this is done in animals often, Ivermectin can cause liver enzyme increases and is rarely used in human beings, although it is known to work, particularly in Africa where it has often been used in those with helminthic eye infections.  In human beings, a 1% topical solution may be used, particularly when the wound is near the eye. Stromectol is one of the brand names of this drug when used in human beings.
6. Improved personal hygiene and better handling of trash can also improve the likelihood of not contracting such an infection.
7. Occasionally antibiotics of certain types may help with secondary bacterial infection, but will not help against the invasion of these larvae. 
8. It is possible simply to cover the wound with generous amounts of vaseline, choking off the larvae. They will slough off when dead by themselves in about 5-8 weeks.  Rarely, a physician will surgically remove them, but this is often not the best course, and leaving them to slough off may be the safest course after thick vaseline application.    Theoretically, vegetable oil or thick mayonnaise could be used, although I would be concerned that food substances may attract other flies.


How such an infection progresses depends largely upon the species of fly and worm that invades the wound.  There are some as mentioned in the cutaneous version above that afflict intact skin.
Infections of all these types may lead to septicemia and to death.


Of course, the most prudent course with regard to Myiasis is PREVENTION.

When someone in your party is injured, wounds should be bandaged when possible. They should stay indoors until the wound has almost healed.   Badly injured people in wilderness situations should be in the most solid and clean structure you have, away from food which might attract flies.  Building this patient a "net bubble" as is often done with children sleeping in parts of Africa in order to avoid malaria, may also be beneficial.
In the cutaneous versions of this disease, the insect often creates an air hole for itself.  You may be able to get the insect to come to the surface for removal by covering the open hole with a thick glob of vaseline, cutting off its air.

I am well aware that this is a difficult topic for many to read about and that the mental images of such are particularly unpleasant.  However, during a migration, a protracted disaster with or without injuries, this can be an issue. Proper management can make a difference in the survival of the infected.

    The pictures of such were so disturbing that I chose not to include them so that our readers were more likely to read and learn from this article.  They certainly can be googled.





 Preparedness Implications:
 In view of this, please purchase extra vaseline, extra gauze for application to wounds and extra amounts of clean roller gauze in order to secure the gauze to such wounds.   Consider buying mosquito netting for your emergency medical kits.   A bug zapper might be a good idea also.