Cordylobia anthropophaga
Encyclopedia
Cordylobia anthropophaga, the mango fly, tumbu fly, tumba fly, putzi fly or skin maggot fly is a species of blow-fly
common in East
and Central Africa
. It is a parasite of large mammal
s (including human
s) during its larva
l stage .C. anthropophaga has been endemic in the subtropics of Africa for more than 135 years and is a common cause of myiasis
in humans in the region.
Its specific epithet anthropophaga derives from the Greek
word anthropophagus, "eater of men".
"The Mode of infection by the Cayor Worm. Doctors Rodhain and Bequaert conclude, from their observations in the Congo Free State
, that Cordylobia anthropophaga (Grunberg) lays its eggs on the ground. The larvae, known generally as Cayor worms, crawl over the soil until they come in contact with man or a mammal, penetrate the skin and lie in the subcutaneous tissue, causing the formation of tumors. On reaching full growth, the larvae leave the host, fall to the ground, bury themselves and there pupate. This fly is said to be the most common cause of human or animal myiasis
in tropical Africa, from Senegal
to Natal
. In the region of Bas-Katanga
where these investigations were made, dogs appeared to be the principal hosts, although
Cordylobia larvae were found also in guinea-pigs, a monkey and two white men. The larvae are always localized on those parts of the hosts which come in immediate contact with the soil." (Ann. Soc. Entom. de Belgique, Iv, pp. 192–197, 1911) summary translation in Entomological News. 1911 Vol. xxii:467.
.
, typically on the backs of arms or about the waist, lower back, or buttocks.
C. anthropophaga rarely causes severe problems, and mainly causes cutaneous myiasis. Geary et al. describe the presentation of cutaneous myiasis caused by the tumbu fly: "At the site of penetration, a red papule forms and gradually enlarges. At first the host may experience only intermittent, slight itching, but pain develops and increases in frequency and intensity as the lesions develop into a furuncle. The furuncle's aperture opens, permitting fluids containing blood and waste products of the maggot to drain."
is defined as an organism that can harbor a pathogen indefinitely with no ill effects. Although C. anthropophaga larvae can cause ill effects for animal hosts, because we are talking about myiasis
in humans, we will consider any animal hosts as reservoirs.
Many animals are hosts of C. anthropophaga. The dog is the most common domestic host and several species of wild rats are the preferred field hosts. Domestic fowl are dead-end hosts, meaning that the larvae cannot develop when they enter the tissue of fowl.
Humans are in fact accidental hosts, which means that tumbu fly larvae do not usually infect humans and we are not necessary for the transmission cycle of the fly.
A vector is an organism that carries the parasites (the larvae) from one host to another. The tumbu fly itself is the vector in a loose sense, because the female deposits the eggs in soil or on damp cloth, where the larvae can hatch and attach to human or animal skin.
to the skin blocks the breathing hole and cuts off the larva’s air supply. This will force the maggot to the surface of the skin as it searches for air. The larvae can then easily be extracted from the skin. If this does not work, local anesthetic can be administered and an incision is made to extract the maggot.
Patients should be monitored for additional and subsequent lesions as development does not occur all at once and some larvae may take longer to reach the prepupal stage. To prevent bacterial infection after removal of the larvae, antibiotics can be administered.
The tumbu fly is endemic to the tropical regions of Africa, south of the Sahara desert. Myiasis caused by C. anthropophaga is the most common cause of myiasis in Africa but can be seen worldwide because of air travel, as human movements carry infestation outside endemic areas.
Blow-fly
Calliphoridae are insects in the Order Diptera, family Calliphoridae...
common in East
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
and Central Africa
Central Africa
Central Africa is a core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, and Rwanda....
. It is a parasite of large mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s (including human
Human
Humans are the only living species in the Homo genus...
s) during its larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
l stage .C. anthropophaga has been endemic in the subtropics of Africa for more than 135 years and is a common cause of myiasis
Myiasis
Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
in humans in the region.
Its specific epithet anthropophaga derives from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
word anthropophagus, "eater of men".
"The Mode of infection by the Cayor Worm. Doctors Rodhain and Bequaert conclude, from their observations in the Congo Free State
Congo Free State
The Congo Free State was a large area in Central Africa which was privately controlled by Leopold II, King of the Belgians. Its origins lay in Leopold's attracting scientific, and humanitarian backing for a non-governmental organization, the Association internationale africaine...
, that Cordylobia anthropophaga (Grunberg) lays its eggs on the ground. The larvae, known generally as Cayor worms, crawl over the soil until they come in contact with man or a mammal, penetrate the skin and lie in the subcutaneous tissue, causing the formation of tumors. On reaching full growth, the larvae leave the host, fall to the ground, bury themselves and there pupate. This fly is said to be the most common cause of human or animal myiasis
Myiasis
Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
in tropical Africa, from Senegal
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
to Natal
Natal, South Africa
Natal is a region in South Africa. It stretches between the Indian Ocean in the south and east, the Drakensberg in the west, and the Lebombo Mountains in the north. The main cities are Pietermaritzburg and Durban...
. In the region of Bas-Katanga
Katanga Province
Katanga Province is one of the provinces of the Democratic Republic of the Congo. Between 1971 and 1997, its official name was Shaba Province. Under the new constitution, the province was to be replaced by four smaller provinces by February 2009; this did not actually take place.Katanga's regional...
where these investigations were made, dogs appeared to be the principal hosts, although
Cordylobia larvae were found also in guinea-pigs, a monkey and two white men. The larvae are always localized on those parts of the hosts which come in immediate contact with the soil." (Ann. Soc. Entom. de Belgique, Iv, pp. 192–197, 1911) summary translation in Entomological News. 1911 Vol. xxii:467.
History of Discovery
The larvae of the tumbu fly, Cordylobia anthropophaga, were first described in Senegal in 1862, and Blanchard first described the adult and gave it its name in 1893. In 1903, Grunbert placed the tumbu fly in a new genus, CordylobiaCordylobia
Cordylobia is a genus of fly from the family Calliphoridae. The larvae of Cordylobia are parasitic on mammals, especially rodents. Two species, C. anthropophaga and C. rodhaini , also are known as parasites of humans. The adult flies feed on rotting fruits, vegetables and animal faeces, and are...
.
Life cycle
Female tumbu flies deposit 100-300 eggs in sandy soil often contaminated with animal feces. The hatched larvae can remain viable in the soil for 9–15 days until they need to find a host for development. If a larva finds a host, it will penetrate the skin and take 8–12 days developing through three larval stages before it reaches the prepupal stage. It will then leave the host, drop to the ground, bury itself, and pupate. It then becomes an adult fly able to reproduce and begin the cycle all over again.Clinical Presentation in Humans
Successful penetrations in humans will result in furuncular (boil-like) myiasisMyiasis
Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
, typically on the backs of arms or about the waist, lower back, or buttocks.
C. anthropophaga rarely causes severe problems, and mainly causes cutaneous myiasis. Geary et al. describe the presentation of cutaneous myiasis caused by the tumbu fly: "At the site of penetration, a red papule forms and gradually enlarges. At first the host may experience only intermittent, slight itching, but pain develops and increases in frequency and intensity as the lesions develop into a furuncle. The furuncle's aperture opens, permitting fluids containing blood and waste products of the maggot to drain."
Transmission
Female tumbu flies lay their eggs in soil contaminated with feces or urine or on damp clothing or bed linens. Damp clothing hanging to dry makes for a perfect spot. The larvae hatch in 2–3 days and attach to unbroken skin and penetrate the skin, producing swelling. If the larvae hatch in soil, any disturbance of the soil causes them to wiggle to the surface to penetrate the skin of the host.Reservoir and Vector
A reservoirReservoir
A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...
is defined as an organism that can harbor a pathogen indefinitely with no ill effects. Although C. anthropophaga larvae can cause ill effects for animal hosts, because we are talking about myiasis
Myiasis
Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
in humans, we will consider any animal hosts as reservoirs.
Many animals are hosts of C. anthropophaga. The dog is the most common domestic host and several species of wild rats are the preferred field hosts. Domestic fowl are dead-end hosts, meaning that the larvae cannot develop when they enter the tissue of fowl.
Humans are in fact accidental hosts, which means that tumbu fly larvae do not usually infect humans and we are not necessary for the transmission cycle of the fly.
A vector is an organism that carries the parasites (the larvae) from one host to another. The tumbu fly itself is the vector in a loose sense, because the female deposits the eggs in soil or on damp cloth, where the larvae can hatch and attach to human or animal skin.
Diagnostics
Cutaneous myiasis caused by the tumbu fly should be suspected when a patient who has just spent time in Africa presents with ulcers or boil-like sores. A definitive diagnose can only be made when the larvae are found. They should be removed and allowed to develop into adult flies for identification purposes.Treatment
In cases of cutaneous myiasis, the larvae are most often removed without an incision. Applying VaselineVaseline
Vaseline is a brand of petroleum jelly based products owned by Anglo-Dutch company Unilever. Products include plain petroleum jelly and a selection of skin creams, soaps, lotions, cleansers, deodorants and personal lubricants....
to the skin blocks the breathing hole and cuts off the larva’s air supply. This will force the maggot to the surface of the skin as it searches for air. The larvae can then easily be extracted from the skin. If this does not work, local anesthetic can be administered and an incision is made to extract the maggot.
Patients should be monitored for additional and subsequent lesions as development does not occur all at once and some larvae may take longer to reach the prepupal stage. To prevent bacterial infection after removal of the larvae, antibiotics can be administered.
Epidemiology
C. anthropophaga is the most common causes of myiasis in Africa (WHO).The tumbu fly is endemic to the tropical regions of Africa, south of the Sahara desert. Myiasis caused by C. anthropophaga is the most common cause of myiasis in Africa but can be seen worldwide because of air travel, as human movements carry infestation outside endemic areas.