When used in infected wounds, the surgical maggots are able to hasten disinfection. A study has been made of the means by which the destruction of bacteria has been brought about. Maggots ingest bacteria in large numbers in feeding upon the necrotic tissues of the wound. Cultures of aseptic dissections of the alimentary tract of maggots showed an abundance of bacteria in the fore-stomach, decreasing numbers in the hind-stomach, and apparently a total disappearance of the bacteria in the intestine. This indicates that ingested bacteria are destroyed in passing through the alimentary tract.

To determine whether or not destruction is caused by digestion, tests were made of the action of digestive enzymes of maggots upon streptococcus hemolyticus and staphylococcus aureus. The enzymes were obtained by maceration of sterile maggot tissue. Results were negative in all cases. This is probably due to death of enzyme-secreting cells during maceration. Livingston and Prince report positive results and state that applications of maggot extract were effective as a curative agent. The data, however, do not make clear how the healing effect obtained was due to maggot extract. Repetition of our tests confirm our negative results.

Maggots feed upon the necrotic and purulent materials within the wound. They thus aid in cleaning up the wound and making its condition less suitable for bacterial growth.

Drainage from the wound is stimulated under maggot treatment. The excessive discharge, which is heavily contaminated with bacteria, assists in wound disinfection.

This investigation indicates that the effects obtained in the maggot treatment of infected wounds are due to the action of living maggots in the wound, and that living maggots can not be eliminated in treatment.

The increased growth of granulation tissue within the wound and its relation to maggot activities is discussed.