Forensic entomology involves the use of insects and other arthropods to estimate the minimum time elapsed since death, referred to as minimum postmortem interval (min PMI). This is based on the assemblage of insects found in association with remains, and most often, the time required for development of the first colonizing insects to develop to their size/ life stage at time of collection. This process involves the accumulation of appropriate data for the development of the species of insect at a variety of relevant temperatures and consideration of the other biotic and abiotic factors that may affect developmental rate. This review considers the approaches to the estimation of min PMI, focusing largely on the age estimation of specimens collected from remains and the limitations that accompany entomology-based PMI estimations. Recent advances and newly developed techniques in the field are reviewed in regard to future potential.

Maggot debridement therapy (MDT) refers to the use of blowfly larvae to clean or debride an infected wound. Most commonly, larvae of Lucilia sericata (Meigen) (Diptera: Calliphoridae) are used, and are sterilized prior to use to ensure no further bacterial infections are introduced during treatment. Current methods sterilize eggs from laboratory-reared blowfly colonies, after which sterile early second instar maggots can be provided to hospitals for use in treatment. Maggots not required for treatment are used for colony regeneration, in which sterility is not maintained. The ability to maintain sterility beyond this would allow further research into fly-bacteria interactions and the effects of different bacteria on the blowfly lifecycle. This study aimed to produce a colony of sterile adults, using current egg sterilization practice, but maintaining sterility through to pupation and emergence. The production of a sterile colony allows further research into the impact of bacteria on fly development and survival. Eggs were placed on a sterile food source within autoclaved plant tissue culture containers to allow growth under sterile conditions. Nutrient agar plating of sterilized and non-sterilized eggs, larvae and adults (post-emergence), as well as the pupation medium and feed source in nutrient broth confirmed the aerobic sterility of all samples involved. The lifecycle of L. sericata was successfully completed through pupation to emergence with no effects on lifespan or oviposition by the newly emerged, sterile adult colony.

Blowfly larvae of Lucilia sericata (Meigen) (Diptera: Calliphoridae) are well established as debridement agents in nonhealing wounds. Maggot therapy (MT) experienced reduced application following adoption of Penicillin and other antibiotics, but the advent of antibiotic resistance and the growing global wound burden have boosted demand for new therapies. The mechanisms of action are well accepted, with debridement, disinfection, biofilm destruction, and inhibition, as well as the stimulation of tissue growth uniformly acknowledged as a remarkable biotherapy. The mechanisms of action, while well-recognized, are still being examined. The efforts to understand isolated aspects of a complex system, have resulted in a tendency to approach the field from simplified viewpoints that remove the holistic system of the larvae. Furthermore, clinical studies have conflated wound debridement and healing in definitions of ‘success’. Thus, both in vitro and clinical studies have reported mixed results, presenting some uncertainty regarding the utility of MT that prohibits routine clinical adoption. This review builds from the generally accepted basic mechanisms to justify a future for MT that encompasses larval-bacterial symbioses as the basis to a holistic system. Symbioses are well documented in the Insecta, and literature in MT supports the existence of established symbiotic associations that provide enhanced debridement action. The future of MT requires consideration of a biological system that confers enhanced antimicrobial action on larvae when selective pre-exposure to carefully selected symbionts is adopted. In treating contemporary infections, there is much to be gained from reflecting on the natural biology of the organism, as MT was used with success long before we sterilized the system.

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Monitoring and collection of fly taxa (Diptera: Calliphoridae; Muscidae; Sarcophagidae) of medical, veterinary, and agricultural importance is often routine practice, providing data on target species presence, distribution and abundance. Collection practices currently involve baited trapping and while an inherent bias accompanying the choice of bait is acknowledged, there is little consistency in bait choice between studies and insufficient assessment of trapping success rates for bait types in current use. This study aimed to examine the effect of bait choice on trapping results for six commonly used bait types; a commercial bait (Envirosafe Fly Attractant, Envirosafe Products) and a combination of mixtures of liver, horse manure and 5% sodium sulfide (Na2S). Trapping success was compared under different seasonal conditions (Summer, Autumn, and Spring) to determine the most attractive bait for calliphorid species, with a secondary comparison of kangaroo versus ox liver occurring under summer conditions. Baits containing Na2S were the most successful in captures of all target taxa, with the addition of manure desirable, yielding increased diversity of taxa. Kangaroo liver baits attracted high numbers of Chrysomya spp. (Robineau-Desvoidy, Diptera: Calliphoridae), while Lucilia spp. (Robineau-Desvoidy, Diptera: Calliphoridae) were comparatively underrepresented in traps using liver alone. The use of a combined ox liver/manure/Na2S bait is recommended as the gold standard for generic screening of necrophagous flies. Where more specific target fly taxa are desired, such as Chrysomya spp. or Lucilia spp. only, alternate baits such as kangaroo or lamb may prove more attractive/successful.