Survey of patients of the Tver region of Russia regarding maggots and maggot therapy

Abstract

The 21st century is seeing a resurgence in the use of maggot therapy—using the physical and biochemical benefits of fly larvae to debride and heal chronic, problematic wounds. Maggots are repulsive to many people, and this could interfere with the acceptance of this modality. Before instituting a maggot therapy programme at our institution, we sought to better understand the psychological barriers that may exist among patients in the Tver region of Russia. Between 2014 and 2016, all patients with arterial insufficiency and trophic ulcers at City Clinical Hospital No. 7 in Tver were administered a survey consisting of six images. Subjects were asked to rank the images in the order of least to most repulsive or disgusting. A total of 576 subjects were recruited for this study: 414 (72%) women and 162 (28%) men. Nearly 60% of subjects considered the images of maggots to be more repulsive than images of gangrenous wounds. This finding is significant because it indicates that much education and support will need to be conducted to address patient fears and anxiety if patients are to be comfortable with a maggot therapy programme.

1. INTRODUCTION

Wound infections develop in as many as 35% to 45% of hospitalised surgical patients.1, 2, 3, 4, 5 Despite recent technological advances and a wealth of antibiotics, purulent wounds and their treatment continue to take a significant economic and social toll. To further complicate matters, the cavalier use of antibiotics without regard for microbial identity, susceptibility, or pathogenicity has contributed to the development of antimicrobial resistance.6, 7, 8, 9, 10, 11, 12

Maggot debridement therapy (MDT, also known as maggot therapy, larval therapy, and biosurgical debridement) is the treatment of wounds using live fly larvae.13 The physical and biochemical properties of the larvae dissolve necrotic tissue, dislodge debris, kill many types of microbes, and reportedly stimulate wound healing.14

The history of maggot therapy goes back hundreds, if not thousands, of years. There is evidence that the larvae were used by the aboriginal Ngemba tribe of New South Wales, Australia;15 by tribal peoples of northern Burma;16 and by Mayan healers in Central America.17

The 21st century is seeing a resurgence in the use of maggot therapy, owing to the growing prevalence of chronic wounds, the growing populations of multi‐resistant bacteria, and the growing literature supporting the benefits of MDT. With this renaissance in maggot therapy, there is also a growing concern about the negative psychological impact of maggots, which may hinder its acceptance. The present study was undertaken in order to explore the extent and prevalence of psychological barriers to maggot therapy in the Tver region of Russia.

2. METHODS

To evaluate patients' feelings towards the idea of maggots and maggot therapy, a survey was designed by the primary author while he was a member of the Student Scientific Society of the Department of General Surgery (Tver State Medical University). The use of physical photographs to identify and associate feelings of disgust was based on the author's exposure to cognitive cards used to probe emotions and associations in children. It was decided to limit the number of photographs to six. The specific photographs used in the study were selected by consensus among 100 student volunteers; the volunteers were themselves selected by the university faculty. The students who selected the photographs did not have wounds.

The survey was administered between 2014 and 2016 to all patients at City Clinical Hospital No. 7 in Tver with arterial and/or neuropathic ulcers. This group of patients was believed to be an appropriate population for maggot therapy should such a programme be implemented.

Subjects were presented with the six photos (Figure 1) in the following manner: the photos were randomly shuffled by the study proctor, the photos were then placed on a desktop, and the study subject was asked to arrange the photos in the order of increasing repulsiveness or disgust. Surveys were completed in private, without additional communication with, or influence by, the proctors or other subjects. The “order of disgust” was recorded for each patient. The percentages of subjects who rated each photo as the most disgusting of the group were calculated with the assistance of Statistica 9.0 (TIBCO Software, Palo Alto, California). Randomness and male: female differences were further evaluated using a chi squared analysis (Excel 2013; Microsoft, Redmond, Washington). Statistically significant differences were defined as having a probability of ≤5% of a type 1 error (P ≤ 0.05).

Figure 1.

Subjects were presented with this set of six images and asked to arrange them in the order that caused them the least to the greatest distress: (1) adult Lucilia sericata; (2) trophic ulcer; (3) sacral ulcer; (4) diabetic foot wound; (5) maggot mass; and (6) mature larvae on an otherwise clean wound

3. RESULTS

A total of 576 subjects were recruited for this study: 414 (72%) women and 162 (28%) men. The majority of respondents—345 people (59.9%)—found the photograph of mature larvae on an otherwise clean wound (Figure 1F) to be the most repulsive of the group. Most other subjects believed that the most objectionable images were the diabetic foot wound (Figure 1D; 16% of respondents); the sacral ulcer (Figure 1C; 11%); or the maggot mass, no wound (Figure 1E; 9% of respondents). Less than 4% of respondents considered the images of either the adult fly (Figure 1A) or the trophic ulcer (Figure 1B) to be the most repulsive of the set. Men and women showed similar patterns in their choices (Figure 2), although a 1.5 times larger percentage of women than men were repulsed by Figure 2F (P < 0.001). Raw data were unavailable for rank order analyses, but by analysing the actual versus “expected” (assuming no difference in probability) results for each photo, only the results of Figure 2C could be attributed to a random ordering of photos (P > 0.05); results for all other photos indicated that the frequency of attitudes were far from random (P < 0.01). Similarly, comparing the difference in frequencies of disgust between women versus men for each image, the differences were statistically significant for each photo (P < 0.01) except in the case of Figure 2C.

Figure 2.

Frequency of negative assessments among male and female respondents. The difference between male and female responses was significant (P < 0.01) in each case, except image (C), based on chi squared analysis. The images shown were: (1) adult Lucilia sericata; (2) trophic ulcer; (3) sacral ulcer; (4) diabetic foot wound; (5) maggot mass; and (6) mature larvae on an otherwise clean wound

4. DISCUSSION

This study suggests that over 50% of our chronic wound patients are repulsed by the idea and image of maggot therapy. Images of maggots and maggot‐infested wounds tended to be identified as more disgusting than images of chronic necrotic (“gangrenous”) wounds. All of the subjects surveyed had chronic wounds that failed to heal despite conventional medical and surgical therapy. As maggot therapy is often very effective for such wounds and has prevented amputations in multiple studies,18, 19, 20, 21 MDT would be a logical treatment choice for many of these patients. However, based on these results, it will be necessary to pay special attention to patients' attitudes towards maggots before proceeding with treatment.

The fact that maggots evoke revulsion and disgust in many of us comes as no surprise; it has been well documented over the years.22 After all, most people associate maggots with death and decomposition. For those of us who have actually come across maggots, it has often been in the context of rotting, stinking rubbish; animal faeces; or a corpse. These are often the images and odours that first come to mind when people think of maggots. Anxiety and disgust towards maggots and maggot therapy in the general public, then, is to be expected.

This study does not examine the prevalence of fear and disgust in the general community, but such a study—better yet, a comparison study—would be valuable. Evaluating the attitudes of people without wounds is important because it is the population to which most health care providers belong, and it is the health care providers who are responsible for considering the option of maggot therapy and presenting that option to their patients. If a therapist is repulsed by the idea of maggot therapy, then he or she may not easily or objectively be able to communicate the options, risks, and benefits to their patients.

One would imagine and hope that patients with chronic wounds would be more open to maggot therapy than people who do not suffer from chronic wounds. At the very least, we can expect them to be less repulsed by the sight and thought of chronic wounds. It may be for this reason that these subjects—all with arterial or neuropathic ulcers—were more disgusted by images of maggots than they were by images of arterial and neuropathic wounds.

This point brings up an important limitation of this study: we have assessed only relative degrees of disgust within the limited context of wounds and maggots, but we have not quantified that disgust in any significant degree nor mapped it out relative to the larger landscape of wound‐related attitudes and fears about pain, body image, social relationships, professional responsibilities, and emotional health.23, 24 We have not identified where “disgust of maggots” lies on the spectrum that includes subjects' attitudes towards other medical and surgical interventions or potential disabilities and disfigurements.25 In short, we have not really determined whether or not these attitudes of relative disgust are sufficient to prevent these or other patients from consenting to maggot therapy should the need for such therapy arise.

Besides the limited subject population (only arterial and neuropathic ulcer patients) and the limited scope of photos (only ulcers, maggots, and flies), some may consider this investigation to be limited by the fact that only “disgust” was evaluated, and that was evaluated only with images. Decisional conflicts have been studied in much greater depth using detailed questionnaires or in‐person subject‐centred interviews.23, 25, 26 Such studies are valuable because they can identify the breadth of attitudes and the factors associated with them. But this was not the intent of the present study. The intent of this study was to identify and crudely quantify an attitude barrier among appropriate candidates for maggot therapy. It is precisely the simplicity—the ease of delivery and interpretation—that makes the present study so useful, if not elegant. Now that the problem of disgust has been clearly documented in our patient population, more detailed analyses (including detailed questionnaires and loosely structured interviews) can be designed, financially supported, and implemented. Perhaps the next studies will even be combined with assessments of the effectiveness of various efforts to overcome these emotional barriers.

What interventions will work best to overcome disgust of maggots? While research can help answer this question, we can already begin with efforts that have proven useful for other fears and prejudices: education, training, and desensitisation for both patients and clinicians. A variety of education aids already exists in English (BTER Foundation) and is being translated into other languages. Another approach is to create dressings that hide the maggots from view. Placing the maggots within a net dressing27 can minimise anxiety according one case report.28 One way to evaluate the effect of such “containment dressings”29 on attitudes would have been to include a photo of contained maggots within the set of photos shown to our subjects, but this was not carried out.

Ultimately, the question that must be asked is whether such attitudes of disgust are enough to prevent patients from undergoing maggot therapy when deemed necessary by their health care team. Indeed, we would argue that, whether or not such emotions turn out to be significant barriers, they should be addressed, and fears should be calmed. Health care providers should always strive to comfort our patients—physically and emotionally. Prior studies suggest that patients usually do not allow their disgust for maggots to prevent them from trying the therapy. This is likely because they are more fearful of other interventions or the prospects of no intervention—again pointing to the need for evaluating attitudes towards maggots within the wider spectrum of patients' attitudes in general.

According to Fear and co‐researchers,30 maggot therapy was expected to be a hard sell to patients, but it was not, especially because most had already heard about the efficacy of MDT. It was harder to convince therapists (doctors and nurses) to use maggot therapy than it was to convince patients. Only after seeing the results first hand did the medical staff become more enthusiastic, eventually resulting in MDT becoming a standard therapy at the facility.

Spilsbury and colleagues31 interviewed 35 patients with at least one venous leg ulcer to understand their thoughts about maggot therapy, compared with hydrogel therapy. Nearly 80% were just as comfortable with the idea of receiving maggot therapy, regardless of how the maggots would be applied or contained. Prior history of other wound treatments or discussions with patients previously treated with maggot therapy were positive influences on decisions to accept maggot therapy. Visual imagery played a significant role among those who were not comfortable with the prospect of maggot therapy. Not surprisingly, the survey also demonstrated that patients can also be affected by the way in which maggot therapy is discussed. As one study subject put it, “the nurses said they put [the maggots] on to eat tissue. I didn't want to hear anymore.”

Prior researchers25, 32 have also looked at the issue of repulsion from a different perspective: how did the actual experience of maggot therapy (not the perception of maggot therapy) affect patients' opinions about the treatment? Kitting25 found that most patients were willing to undergo maggot therapy if they were comfortable with their health care provider and if they believed they were given an informed choice. Even when subjects were initially repelled by the idea, fear soon subsided once maggot therapy began. Steenvoorde32 discovered that 95% of 37 respondents were satisfied enough to recommend maggot therapy to others, even though four patients (11%) said that they, themselves, would not undergo maggot therapy again (three of those four had failed to respond to treatment and ultimately required amputation). Even adverse events (odour, pain, itching) did not discourage patients. All of the patients who suffered these adverse events said that they would undergo MDT again if they had another wound. Indeed, several studies28, 33, 34 have discovered that fear and disgust did not inhibit patients as much as they inhibited health care providers from using maggot therapy.

One of the surprising findings of the study reported herein was the gender difference: 1.5 times as many women, compared with men, were repulsed by Figure 2F (P < 0.001). Differences may be the result of prior desensitisation of men, brought about by greater exposures to maggots in the wild or in the kitchen, or because of greater desensitisation of the women to wounds. Perhaps this discrepancy is because of cultural differences that lead men to have a greater exposure to maggots or simply a cultural pressure to suppress feelings of disgust. It is well accepted that cultural upbringing plays a major role in what we consider frightening and disgusting.35, 36, 37, 38 The whole idea of cultural pressures or experiences playing a role in the differences observed between our male and female subjects should prompt future researchers to attempt to associate differences in attitudes with individual demographic and experiential histories. Such personal data were not collected within this study but could be quite enlightening.

If designing a similar study of photo‐prompted responses, one additional improvement we would recommend is to track the order or placement of images presented to patients. We attempted to control the effect of order by having the proctors randomly shuffling the images before laying them out on a table, but that order may not have been as random as we had intended. If not adequately randomised, the order may very well have had an effect on subjects' ranking of the disgusting images as it does on other study outcomes.39, 40, 41 The only way to sort that out is to both randomise and record the order or arrangement of those images and then correlate those patterns with subjects' responses.

Morozov AM, Sherman RA. Survey of patients of the Tver region of Russia regarding maggots and maggot therapy. Int Wound J. 2019;16:401–405. 10.1111/iwj.13046