Kenyan scientists use maggots to clean, cure chronic wounds

KARI Director of Trypanosomiasis Research Centre Dr Phoebe Mukiria explains ‘maggot therapy’ during Kenya Science Journalists Congress held at Kenya Medical Research Institute, Nairobi, last week. [PHOTO: PHILIP MUASYA/STANDARD]

By PHILIP MUASYA

KENYA: The green toilet fly is an unwanted guest in many people’s homes.

Owing to its living environments, which include latrines, toilets and hovering over dead rotting carcasses, many people swat it off immediately it perches.

Its sight is enough to make one lose appetite.

But for Kenyan scientists, the fly is a valuable insect, whose larvae (maggots) would soon be used for cleaning and cure of chronic wounds that are resistant to antibiotics.

Such festering wounds may be caused by grisly road accidents or diseases such as diabetes and cancer and take inordinate time to cure.

Dr Phoebe Mukiria, Director of Trypanosomiasis Research Centre at Kenya Agricultural Research Institute (KARI), says the larvae stage (maggots) of the fly scientifically known as Lucilia sericata has been shown to be effective in cleaning chronic wounds.

Cleaning process

According to Dr Mukiria, the maggots feed only on dead, rotting tissue of the wound, in a cleaning process called debridement (removal of dead tissue).

She says the maggots have modified mandibles (mouth hooks) and also have rough bumps on their bodies which poke and scratch the dead milky tissue of the wound, one of essential mechanisms that debrides the wound.

“The maggots’ secretions dissolve dead tissue and suck it up hence cleaning the wound. The results so far are very encouraging and doctors are very happy,” says Dr Mukiria who, jointly with other doctors, is conducting trials at Kenyatta National Hospital (KNH).

It is this nature of maggots that is being used to advance the treatment of wounds in what is called maggot therapy. Dr Mukiria says this method of cleaning wounds reduces time for hospitalisation and re-infection of the wound.

The maggots are being grown in Petri dishes at KARI where they are kept in a special diet of liver.

After two days they are sterilised and washed with distilled water then packaged in a maggot sac, ready for use. After it is applied on the wound, the maggot sac is changed after every two to three days since the maggots are ferocious ‘eaters’.

Dr Mukiria notes that maggot therapy does not hurt because they do not bite neither do they reproduce in the wound.

Allaying fears that the maggots might burrow themselves in the wound, Mukiria says: “Once done feeding on the dead tissue, they just pull out. They can’t burrow themselves in the wound since they only feed on dead tissue.”

The maggot movement within the wound improves blood circulation which accelerates the healing process of the wound, she explains, noting that maggot therapy to wounds that are not responsive to antibiotics is dramatic.

The medic explains that after the maggot therapy, some wounds resolve themselves while others might need more medical interventions like grafting.

“After the cleaning exercise, health professionals will be able to determine which wounds are suitable for grafting,” she says.

Dr Kimani Wanjeri who is also involved in the research trials at KNH says the method would substantially reduce the period patients stay in hospitals.

Reaction to antibiotics

“Wounds such as those caused by diabetes and cancer may not react to antibiotics and need periodic cleaning and dressing to prevent them from worsening.

Maggot therapy has proven to be very effective in cleaning them,” explains Dr Wanjeri.

He says that through maggot therapy, even the worst wounds would be cleaned in 10 days and hopes that this method would be added to the available treatment methods such as surgical removal of rotten tissue which usually prolongs treatment.

The Ethical Review Committee of KNH will review the results for potential approval once trials are complete.

According to a study, maggots were widely used during the 18th and 19th century wars as well as during World War I before the advent of antibiotics.

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