Maggots in wounds

Life cycle of a fly

First it’s important to understand the life cycle of a maggot. They hatch from eggs laid by flies who have an immense sense of smell and seek out food sources for their offspring. This will usually be animal cadavers but the malodour of a wound can also attract them. When the eggs hatch the maggots can wriggle through to the wound even if bandages are in the way. It’s unlikely you will find them under a sealed dressing such as Mepilex border.

Read up on Myiasis: Maggot infestation

Concerns

Often the concern about maggots is the risk of causing infection. Also the feeling they reflect badly on our clinical practice (what did we do wrong?) with an idea that flies are associated with “dirtiness”.

So let’s deal with these:

Risk of infection

According to The Nursing Times article on maggots in the UK will want to feed on devitalised tissue only. However, if your patient has returned from tropical travel then do consider the fly source might be different and they may feed on healthy tissue.

Risk of infection from the maggots is going to be low. In fact they will clean the wound of dead tissue and bacteria as well as stimulating granulation tissue growth. Maggots will be an unlikely source of infection. Contamination may occur from the fly’s feet as we don’t know where they have previously been.

Clinical practice

Please do not blame yourself or your colleagues if maggots are found in the wound. It’s an act of nature and not a reflection on your dressing technique or even necessarily the environment. Even our skilled leg ulcer nurses have reported a patient with maggots who had compression bandages applied in a clean, fly free clinic only to return one week later with an infestation.

Dirtiness

In warm weather when doors and windows are open flies will enter uninvited despite the cleanliness of the home.

Advice to patients

Patients may be concerned and upset when maggots are discovered. They may not know they are there and they can be a shock to patients, relatives and staff. The benefit of maggots in wound care is well documented. Educate them on the above and reassure them it has nothing to do with the clinician’s technique on dressing change or anything they have done.

Advise them to use fly deterrents and be vigilant in warm weather.

What to do when an infestation of maggots is found in a wound

1. Advise, educate and reassure the patient.
2. Remove the maggots as best as you are able, using tap water or a shower. Contain them in a plastic bag and seal so that it can be disposed of.
3. Review the patient and complete a full wound assessment on SystmOne. Assess the exudate levels, has it increased? Strikethrough may be what attracted the fly, therefore, consider daily dressing changes if you are concerned this may re-occur. For leg ulcers it wound be a good opportunity to encourage those avoiding compression to reconsider!
4. Re-dress the wound as usual according to the care plan.
5. Document that maggots have been found and discuss this at handover.
6. Antibiotics will not support getting rid of the maggots but maggots will support ingesting bacteria and killing them in their gut. Follow the Wound Infection Framework if you suspect the wound has become infected.
7. Unless the patient is unwell and showing signs of infection or sepsis, hospital admission is not necessary for an infestation of maggots alone.