Plasmodium circumflexum is a parasite of the genus Plasmodium

Plasmodium

Plasmodium is a genus of parasitic protists. Infection by these organisms is known as malaria. The genus Plasmodium was described in 1885 by Ettore Marchiafava and Angelo Celli. Currently over 200 species of this genus are recognized and new species continue to be described.Of the over 200 known...

subgenus Giovannolaia

Giovannolaia

Giovanolaia is a subgenus of the genus Plasmodium created by Corradetti et al. in 1963. The parasites within this subgenus infect birds.- Diagnostic features :Species in the subgenus Giovanolaia have the following characteristics:...

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Like all Plasmodium species P. circumflexum has both vertebrate

Vertebrate

Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...

 and insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

 hosts. The vertebrate hosts for this parasite are bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s.

Description

The parasite was first described by Kikuth in 1931 in a juniper thrush. It may have been the same species previous described by Labbe in 1894 who thought it was a species of Haemoproteus

Haemoproteus

Haemoproteus is a genus of protozoa that are parasitic in birds, reptiles and amphibians. Its name is derived from Greek: Haima - blood and Proteus - a sea god who had the power of assuming different shapes. The name Haemoproteus was first used in the description of Haemoproteus columbae in the...

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Schizonts: these are large and when mature may entirely encircle the erythrocyte nucleus.

Merozoites: each schizont gives rise to 13-30 merozoites (mean 19.8: standard deviation 5).

Gametocytes: these are large and when mature may entirely encircle the erythrocyte nucleus.

Geographical occurrence

This parasite is found in Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

, Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

, Malaysia, Morocco

Morocco

Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

, South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, Sri Lanka

Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

 and the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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Vectors

Culiseta morsitans

Mansonia crassipes

Theobaldia annulata

Sporogeny but not transmission has been recorded in Mansonia perturbans.

Clinical features and host pathology

P. circumflexum infects the sharp-shinned hawk (Accipiter striatus), red-winged blackbird (Agelaius phoeniceus), wood duck (Aix sponsa), canvasbacks (Aythya valisineria), blue jay (Cyanocitta cristata), Cape May warbler (Dendroica tigrina), gray cat bird (Dumella carolinensis), slate colour junicao (Junico hymenalis), song sparrow (Melospiza melodia), common merganser (Mergus merganser), cowbird (Molothrus ater ater), finch (Richmondena cardinalis cardinalis), trumpeter swan (Olor buccinator), chestnut-tailed starling (Sturnus malabaricus), brown thrasher (Toxostomar ufum), white throated sparrow (Tromotrichio albicolis), American robin (Turdus migratorius), juniper thrush (Turdus pilaris), wild guineafowl (Numida meleagris) and white-throated sparrow (Zonotrichia albicollis).
In wild guinea fowl the pathological features in acute cases include anaemia, jaundice and splenomegaly; in the subacute cases severe splenomegaly, right ventricular hypertrophy and multifocal interstitial myocarditis.

External links

• Picture of eythroctic forms - http://workforce.cup.edu/Buckelew/Plasmodium%20circumflexum.htm