Explainer: How maggots can live inside a human being

A screengrab of a live maggot pressed out of a child's leg [Facebook Naitwa Faiza]

A few weeks ago, a woman going by the name Naitwa Faiza Karaz on Facebook shared how worms had crawled out of her son's body.

In the description, the mother said her son had boils and when she pressed them, live maggots crawled out.

“I noticed my son had four boils, one on his head, his chest, his leg and his fingers. They were so small I assumed they are slight infections and would go. His doctor recommended an antibiotic cream…. Sometimes my son will be shouting “his head, his head” or “his leg”, I assumed it was aches that the boil was giving him (sic) and I gave him just (sic) paracetamol. His teachers also claimed that he usually shouts “my head, my head” in school. On the third day, as I got from work, I checked the hand and saw that the boil had opened (sic). I saw something like pus. Lo and behold when I pressed it, a live maggot came out!

“I wanted to faint. I called my husband and also called the doctor. It was already about 6pm, we couldn’t go to the hospital. So the doctor advised I pressed (sic) all of them which I did. 4 live maggots in all. I cleaned the wound with spirit. And the doctor placed him on antibiotics, my son was able to have a restful sleep compared to the past 4 days. The doctor eventually told me about the tumbu fly…” read her post.

The Standard Explainer desk decided to check the claim that maggots can live in a human who is alive. We spoke to Dr Syama Sinuff, a Consultant Paediatrician at the Aga Khan University Hospital, who explained how live maggots can end up inside a human being.

The tumbu fly is also commonly known as the mango, putsi or skin maggot fly. The larvae of the tumbu fly are parasitic and when they get under the skin of mammals – including humans – they can live there until they hatch into maggots. This parasitic infestation is called cutaneous myiasis.

Dr Sinuff breaks down what causes this parasitic infestation, how to avoid the tumbu fly and what to do when you get infested.

Q: What would be the simplest way to explain tumbu fly?

The tumbu fly is endemic to sub-Saharan Africa. It is a large, brownish-yellow fly with black abdominal spots and brown wings.

Which season is the tumbu fly infestation common?

Infestation may increase after periods of heavy rainfall.

How do the maggots end up under a human being’s skin?

In Kenya and Africa, the type of mango fly causing symptoms is called C. anthropophaga.

The female tumbu fly prefers to lay eggs on urine/faecal scented dirt or sand. They may also lay their eggs in the seams of clothing, bedding, towels, and other soft materials that have been left outdoors.

People are likely to get exposed when they spread their clothes outside to dry. The flies lay their eggs on these clothes and the hatched larvae can survive on the clothes for up to 15 days.

Once the clothes are worn, the body heat activates the larvae which penetrate the skin with their sharp tentacles.

The tumbu fly larvae can survive without a host for up to two weeks. Once the larvae make contact with a mammalian host like a dog, rodent, or a human, they painlessly burrow under the skin where the larvae feed on subcutaneous living tissue for two to three weeks as they continue to grow. During this time, a red, solid boil with a hole or tiny black dot on top will form and grow.

The boil is what contains the maggot worm.

What are the symptoms of tumbu fly infestation?

As the larvae continues to mature into adult maggots, the boil starts to fill with pus. It may be possible to see or feel the larvae wiggling under the skin during this time.

Once the larvae have penetrated the skin it may take several days for symptoms to appear.

Symptoms may include itching. It may either be mild or intense. Some people may only experience a vague sense of discomfort in the initial stage.

The level of itchiness will be determined by the number of larvae which have infested the skin and as time goes by, intense pain and discomfort may develop.

Blister-like lesions may then appear which look like pimples within a few days of infestation. The lesions look like mosquito bites and within two to six days, turn into boils.

The boils increase in size to about one inch as the larvae grows. The area surrounding the boil may appear to be inflamed and red. Larvae may be seen wiggling in each boil.

Other symptoms which may be experienced include fever and a high heart rate.

How do you treat the boil?

The larvae may be suffocated by applying petroleum jelly, liquid paraffin, or sticking adhesive tape. This is less invasive and may lead to the larvae being forced to wriggle out in search of oxygen.

The tip of the boil will have a tiny air hole or black dot on top. This dot is the top of a tube through which the larvae breathe. Application of the jelly also leads to loosening of the grip of the larvae to the wall of the cavity, hence, making mechanical extraction of the larvae easier.

The lack of oxygen to the larvae and suffocating them with the agents mentioned above may force the larvae out and aid the doctor to remove the rest of the body of the larvae using forceps.

How does one prevent getting infested with the tumbu fly?

Clothing and beddings that have been dried outside must be carefully ironed and close attention should be paid to the seams. Avoid walking barefoot outdoors and practice good hygiene habits at all times.

Dogs and rodents are hosts as well to the larvae. It would be advisable to dry clothes off the ground and in full sunlight and preferably in a ventilated area under a mosquito net. If you are travelling to an endemic area, avoid sleeping or sunbathing on the ground.

Also try and wear long pants and long sleeves. The tumbu fly can also be eliminated by using insecticides. Get your pet checked by your vet if you suspect that it is infected. 

Is it necessary to visit a doctor?

Seek a doctor’s opinion as soon as you can. This will help reduce the risk of infection spreading and will also relieve discomfort. The doctor can also examine the whole body for other sites of infestation as it is possible to have multiple sites of infestation present on your body.

A doctor will be able to extract the larvae and reduce the risk of complications from occurring which may happen if you attempt to remove the larvae yourself at home.