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A 58-year-old man called 911 because his 54-year-old brother fell in their apartment. When emergency medical services (EMS) arrived at the apartment, they found it to be infested with insects and covered with animal feces. The EMS personnel deemed the apartment unfit for human habitation and were

The larvae of the common green bottle fly ( Lucilia sericata ) produce antibacterial secretions that have a therapeutic effect on chronic and nonhealing wounds. Recent developments in insect biotechnology have made it possible to use these larvae as a source of novel anti-infectives. Here, we report the application of next-generation RNA sequencing (RNA-Seq) to characterize the transcriptomes of the larval glands, crop, and gut, which contribute to the synthesis of antimicrobial peptides (AMPs) and proteins secreted into wounds. Our data confirm that L. sericata larvae have adapted in order to colonize microbially contaminated habitats, such as carrion and necrotic wounds, and are protected against infection by a diverse spectrum of AMPs. L. sericata AMPs include not only lucifensin and lucimycin but also novel attacins, cecropins, diptericins, proline-rich peptides, and sarcotoxins. We identified 47 genes encoding putative AMPs and produced 23 as synthetic analogs, among which some displayed activities against a broad spectrum of microbial pathogens, including Pseudomonas aeruginosa , Proteus vulgaris , and Enterococcus faecalis . Against Escherichia coli (Gram negative) and Micrococcus luteus (Gram positive), we found mostly additive effects but also synergistic activity when selected AMPs were tested in combination. The AMPs that are easy to synthesize are currently being produced in bulk to allow their evaluation as novel anti-infectives that can be formulated in hydrogels to produce therapeutic wound dressings and adhesive bandages.

We report three cases of infection due to the Gram-negative rod Ignatzschineria ( Schineria ) indica involving bacteremia and the urinary tract. Two cases were clearly associated with maggot infestation, and the third could conceivably have had unrecognized maggot infestation of the urinary tract. We believe these cases to be the first I. indica infections reported in association with maggot infestation and myiasis.

Staphylococcus aureus and Staphylococcus epidermidis biofilms cause chronic infections due to their ability to form biofilms. The excretions/secretions of Lucilia sericata larvae (maggots) have effective activity for debridement and disruption of bacterial biofilms. In this paper, we demonstrate how chymotrypsin derived from maggot excretions/secretions disrupts protein-dependent bacterial biofilm formation mechanisms.

Already well known for their wound-healing powers, maggots and their by-products also can disrupt biofilms formed by pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa, according to Mariena van der Plas of Leiden University Medical Center in Leiden, the Netherlands, and her colleagues. “The bioactive components of maggot excretions and secretions (ES) may be very promising candidates for the development of a new treatment for chronic, infected wounds,” she noted during a poster session at the 2007 ASM Conference on Biofilms, convened in Quebec City, Canada, last March. Although disruptive but not themselves lethal to biofilms, ES components might prove a useful treatment if they render pathogens released from those biofilms again susceptible to conventional antibiotics.

Groups of immobilized gnotobiotic houseflies, Musca domestica L., were mono-contaminated with graded doses of Salmonella typhimurium , bicontaminated with S. typhimurium and Proteus mirabilis , and multicontaminated with S. typhimurium and a mouse fecal flora. Of 45 flies fed an average of 22 Salmonella cells alone, 26 showed bacterial multiplication, up to 1.4 × 10 7 in one case. There was a fairly consistent increase in percentage of Salmonella excreters with increasing input, so that all flies given 10 4 and 10 5 cells shed Salmonella some time during an observation period of 8 to 13 days. Multiplication, however, reached higher levels in flies given 10 2 or 10 3 organisms. A high input was not necessary to produce a high proportion of Salmonella excreters. Among 22 flies given an average of 90 Salmonella cells, multiplication occurred in 17 and 18 became excreters. Antagonism between P. mirabilis and S. typhimurium , which was previously described in the blowfly maggot tract, also occurred in the gut of the adult housefly. With an input of 10 3 cells each of Salmonella and Proteus , there was a reduction of Salmonella excreters to 27% on the first day and elimination by the second day. With a normal fecal flora which contained no demonstrable P. mirabilis , 37% of the flies were still excreting Salmonella on the fourth day, but not by day 6; among flies fed Salmonella alone at the same input, the organism was excreted by 87% on the first day and 62% on the second day, and outputs continued for at least 8 days. Salmonella was lodged mainly in the mid- and hindgut 3 days after the infective meal, minimizing transmission through vomit. Comparison studies with the common green bottle fly, Phaenicia sericata Mg., showed it to be more resistant than the housefly to establishment and multiplication of S. typhimurium .

Survivorship of Salmonella typhimurium, Streptococcus faecalis, Proteus mirabilis , and Pseudomonas aeruginosa was studied in dibiotic and tribiotic interactions in vitro and in various regions of the digestive tract of the blow fly, Calliphora vicina . In dibiotic interactions, Salmonella typhimurium dominated Streptococcus faecalis and was dominated by P. mirabilis , but in neither case was it eliminated from the larval gut. In tribiotic interactions, there was synergic suppression and a definite trend toward elimination of Salmonella typhimurium from the gut. This trend approaches but does not match the total exclusion of S. typhimurium from the gut of maggots with a normal flora. Bacterial survival in the gut of the fly is discussed in relation to doubling time, sweep-out rate of the maggot and prepupal gut, and the midgut bactericide.