Copyright EMAP Publishing 2021 This article is not for distribution except for journal club use Clinical Practice Keywords Maggot therapy/Wound care/Wound healing Review This article has been Wound care double-blind peer reviewed In this article... ● Evidence supporting maggot therapy in wound care ● Indications for use and how the process works ● Patient perception of the treatment The principles of maggot therapy and its role in contemporary wound care Key points Author Yamni Nigam is professor (anatomy and physiology), College of Human and Maggot therapy has Health Sciences, Swansea University. been available on NHS prescription Abstract Maggot therapy is becoming increasingly established as an option for the since 2004 debridement and treatment of sloughy, necrotic wounds. Although used tentatively NT SELF- over the previous few decades, it became more widespread following its availability ASSESSMENT Maggots are on NHS prescription in 2004. Since then, the scientific and clinical evidence for the Test your clinically effective efficacy of maggot therapy has mounted considerably, and it has been shown to be knowledge. for the debridement effective, not only for wound debridement but also in reducing the bacterial burden After reading this of sloughy, necrotic of a wound and accelerating wound healing. This article reviews current evidence, article go to chronic wounds and discusses the clinical indications for use, and the rearing and clinical application nursingtimes.net/ of maggots, as well as patient and health provider perceptions of maggot therapy. NTSAMaggots If you score 80% Secondary benefits or more, you will of maggot therapy Citation Nigam Y (2021) The principles of maggot therapy and its role in receive a certificate include reduction of contemporary wound care. Nursing Times [online]; 117: 9, 39-44. that you can use wound bacterial as revalidation evidence. load and an acceleration of ll health professionals are History of maggot therapy wound healing acutely aware of the mounting Knowledge of the improvement in the burden and cost of wound wound state as a consequence of maggot Maggots can be Amanagement. The develop- infestation dates back centuries, but docu- applied clinically ment of non-healing wounds is often an mented evidence is mainly through mili- directly to the unfortunate and inevitable consequence of tary records. It was Dr William Baer who wound or in bagged the presence of certain chronic conditions, wrote about the positive effects and out- form and are usually such as chronic obstructive pulmonary comes of unintentional maggot infesta- left on a wound for disease, cardiovascular disease and dia- tion on open battlefield wounds inflicted four days before betes. The underlying pathology of on soldiers in the First World War (Man- removal certain conditions, including diabetes, ring and Calhoun, 2011). After the war, in makes it highly probable that the resulting his role as professor of orthopaedic sur- For some patients, wounds may become necrotic, infected gery at John Hopkins School of Medicine, there may be and indolent. in the US, he initiated the use of sterile associated side- Such wounds can cause severe discom- maggots as a reputable method of wound effects of bleeding fort and distress to patients. They are often therapy. His pioneering work meant the and pain, and nurses notoriously difficult to treat and tend to use of maggot therapy began to flourish in are advised to harbour antibiotic-resistant strains of bac- the 1930s and early 1940s, and was widely monitor such teria or bacterial biofilm, which can drasti- used in hospitals in the US and Canada. patients closely cally impede healing. Effective wound By the mid-1940s, following the first debridement and a reduction in bacterial clinical use of penicillin, the industrial burden are an essential part of wound man- antibiotic era commenced in earnest; this agement and, in the search for more effec- ended the use of maggots as the steady and tive clinical management, numerous new consistent overuse of antibiotics pro- chronic wound treatment modalities have gressed. Over time, several species and been introduced over the past two decades. strains of bacteria emerged that were Nursing Times [online] September 2021 / Vol 117 Issue 9 39 www.nursingtimes.net Copyright EMAP Publishing 2021 This article is not for distribution except for journal club use Clinical Practice Review Fig 1. Life cycle of the medicinal maggot, Lucilia sericata slowly becoming more and more resistant For clinical use, disinfected eggs hatch ● Disinfection (reducing bacterial to almost any antibiotic therapy. We now under sterile conditions. Upon emerging, infection and biofilm burden); face a global public-health crisis, with a and just prior to being packaged for ● Helping to accelerate wound healing. worldwide rise in patients with antibiotic- delivery, hungry first-stage (L1) larvae are Advances in our understanding of resistant wound infections (Alfadli et al, fed once on a high-protein cereal-based maggot therapy and its treatment stem 2018). Consequently, maggot therapy is diet, so they can survive for up to 24 hours from clinical reports and the results of lab- being revisited and advocated for debride- in transit. Once placed on a wound, the oratory investigations in these three areas. ment, disinfection and the ultimate larvae can feed and grow to their final third healing of necrotic tissue. stage (L3); they usually remain on the Wound debridement Currently, there are several specialist wound for four days before being removed. The primary goal of maggot therapy is to laboratories worldwide that are licensed to Used larvae are treated as infectious clin- carry out the process of wound debride- aseptically produce clinical-grade mag- ical waste. ment. The ability of L sericata larvae to gots. ‘Medicinal maggots’ can be ordered If a wound is assessed as suitable for achieve speedy and effective debridement through these companies and supplied treatment with maggots, the therapy can is attributed to their highly necrophagous directly to hospitals and clinical centres progress under clinical guidance. Suitable nature (ability to rapidly consume and for the treatment of all sorts of wounds, wounds include any type of chronic wound ingest dead tissue). including leg ulcers, pressure ulcers, and that has moist slough or necrotic tissue on diabetic and necrotic ulcers, as well as its floor (Naik and Harding, 2017). The Clinical evidence base infected surgical wounds, burns and application of maggots requires appropri- The efficacy of maggot therapy in wound trauma injuries. ately trained clinicians to place a number debridement is proven. Since its resur- of tiny larvae onto a wound, either as free- gence in the US and UK in the 1990s, clin- What is maggot therapy? range or bagged maggots. ical studies have assessed the success of Maggot therapy, also known as larval Over the next few days, the larvae not larval therapy compared with conven- therapy, is one option available for treating only clear away the dead, sloughy or tional treatment methods for debriding chronic, infected, necrotic and sloughy necrotic tissue in the wound, but also chronic wounds (Dumville et al, 2009a; wounds. The maggots used are special eliminate infection. Once the larvae are Opletalová et al, 2012). clinical-grade, aseptically reared larvae of removed, the wound is reassessed for fur- Sun et al’s (2014) systematic review of the common greenbottle fly (Lucilia seri- ther therapy. Maggots are now thought to clinical studies from 2000-2014 incorpo- cata). Fig 1 outlines the life cycle of this benefit wounds in three ways: rated 12 comparative studies, including six FRANCES THORNTON, SWANSEA UNIVERSITY SWANSEA THORNTON, FRANCES medicinal maggot. ● Debridement (getting rid of dead tissue); randomised controlled trials. Based on an Nursing Times [online] September 2021 / Vol 117 Issue 9 40 www.nursingtimes.net Copyright EMAP Publishing 2021 This article is not for distribution except for journal club use Clinical Practice For more articles on tissue viability, go to Review nursingtimes.net/tissue-viability analysis of these 12 studies, the authors secretions being caused by a complex mix also received maggot therapy. A swab cul- concluded that larval therapy was more of enzymes. ture was collected before and after each effective and more efficient in the debride- maggot application and analysed for the ment of chronic ulcers compared with Bacterial burden presence of Staphylococcus aureus and Pseu- conventional treatments (Sun et al, 2014). While debridement is often the primary domonas aeruginosa. In the maggot treat- As an example, one randomised controlled aim in the clinical use of maggot therapy, ment group, cases of S aureus infection trial compared the clinical effectiveness of evidence is accumulating that the therapy reduced after 48 hours of treatment, with a a larval therapy dressing with a standard contributes to other aspects of wound further reduction after a second applica- debridement technique (hydrogel) on treatment (Pritchard and Nigam, 2013). In tion of larvae. Cases of P aeruginosa reduced venous or mixed arterial/venous leg ulcers. particular, larvae have been shown to have too, but only after a second maggot treat- The analysis revealed that 96.9% of ulcers a significant antibacterial effect on the ment. In the control group, which had no were debrided in the larvae arm compared wound surface, not only by the removal of maggot therapy, no reduction in cases