Plasmodium vivax
Mature P. vivax trophozoite
Scientific classification
Kingdom: Protista Phylum: Apicomplexa Class: Aconoidasida Order: Haemosporida Family: Plasmodiidae Genus: Plasmodium Species: P. vivax
Binomial name
Plasmodium vivax Grassi & Feletti 1890

The parasite Plasmodium vivax is the most frequent and widely distributed cause of benign, but recurring (tertian), malaria. It is one of four species of parasite that commonly cause malaria infection in humans. It is less virulent than Plasmodium falciparum, the deadliest of the four, and seldom fatal. P. vivax is passed on by the female Anopheles mosquito, since it is the only gender that bites. Image File history File links Plasmodium_vivax_01. ... The activated, feeding stage in the life cycle of protozoan parasites. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Typical phyla Rhodophyta (red algae) Chromista Heterokontophyta (heterokonts) Haptophyta Cryptophyta (cryptomonads) Alveolates Pyrrhophyta (dinoflagellates) Apicomplexa Ciliophora (ciliates) Excavates Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Amoebozoa Choanozoa Many others; classification varies The Kingdom Protista or Protoctista is one of the commonly recognized biological kingdoms, including all the eukaryotes except for... Classes & Subclasses Aconoidasida Haemosporasina Piroplasmasina Blastocystea Conoidasida Coccidiasina Gregarinasina The Apicomplexa are a large group of protozoa, characterized by the presence of a unique organelle called an apical complex. ... Orders Haemosporida Piroplasmida The Aconoidasida are a class of Apicomplexan parasites. ... The Haemosporida are an order of the class Aconoidasida and include the protozoa responsible for the disease malaria. ... The Plasmodiidae are a family of apicomplexan parasites, including the genus Plasmodium, which is responsible for malaria. ... Red blood cell infected with malaria A plasmodium[[1]] is also the macroscopic form of the unusual protist known as slime moulds. ... In biology, binomial nomenclature is the formal method of naming species. ... Giovanni Battista Grassi (1854-1925) was an Italian zoologist, known for work demonstrating that mosquitos carry the malaria plasmodium in their digestive tract, on the embryological development of honey bees, on parasites, particularly the vine parasite phylloxera, migrations and metamorphosis in eels, and on termites. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... Malaria is a vector-borne infectious disease that is widespread in tropical and subtropical regions. ... Binomial name Plasmodium falciparum Welch, 1897 Plasmodium falciparum is a protozoan parasite, one of the species of Plasmodium that cause malaria in humans. ... Some Species Anopheles atroparvus Anopheles beklemishevi Anopheles coustani Anopheles crypticus Anopheles culicifacies Anopheles farauti Anopheles fluviatilis Anopheles forattinii Anopheles funestus Anopheles gambiae Anopheles grabhamii Anopheles hailarensis Anopheles halophylus Anopheles hyrcanus Anopheles introlatus Anopheles kosiensis Anopheles latens Anopheles maculipennis Anopheles minimus Anopheles moucheti Anopheles nili Anopheles ovengensis Anopheles pampanae Anopheles peytoni...

Asexual forms:

• Immature trophozoites (Ring or signet-ring shaped), about 1/3 of the diameter of a RBC.
• Mature trophozoites: Very irregular and delicate (described as amoeboid); many pseudopodial processes seen. Presence of fine grains of brown pigment (malarial pigment) or hematin probably derived from the haemoglobin of the infected red blood cell.
• Schizonts (also called meronts): As large as a normal red cell; thus the parasitized corpuslce becomes distended and larger than normal. there are about sixteen merozoites.

Sexual forms: Gametocytes: Round. The gametocytes of P. vivax are commonly found in the peripheral blood at about the end of the first week of parasitemia.

Microscopically, the parasitised red blood cell is up to twice as large as a normal cell and fine pink Schüffner's stippling are seen on the cell's surface. The parasite within it is often wildly irregular in shape (described as "amoeboid"). Schizonts of P. vivax have up to twenty merozoites within them. It is rare to see cells with more than one parasite within them. Merozoites will only attach to immature blood cell (reticulocytes) and therefore it is unusual to see more than 3% of all circulating erythrocytes parasitised. Human red blood cells Red blood cells are the most common type of blood cell and the vertebrate bodys principal means of delivering oxygen from the lungs or gills to body tissues via the blood. ... A merozoite is a daughter cell of protozoan parasites. ...

P. vivax and P. ovale that has been sitting in EDTA for more than half-an-hour before the blood film is made will look very similar in appearance to P. malariae, which is an important reason to warn the laboratory immediately when the blood sample is drawn so they can process the sample as soon as it arrives. Blood films are preferably must be made within half-an-hour of the blood being drawn and must certainly be made within an hour of the blood being drawn. Binomial name Plasmodium ovale , Plasmodium ovale is a species of parasitic protozoa that causes benign tertian malaria in humans. ... EDTA is a popular acronym for the chemical compound ethylenediaminetetraacetic acid. ... Binomial name Plasmodium malariae Feletti & Grassi, 1889 Plasmodium malariae is a parasitic protozoa that causes malaria in dogs. ...

The incubation period for the infection usually ranges from ten to seventeen days and sometimes up to a year. Persistent liver stages allow relapse up to five years after elimination of red blood cell stages and clinical cure. The word incubation (from the Latin incubare, to lie upon) can mean the following: In chemistry or biochemistry, incubation refers to maintaining a system under specific conditions in order to promote a particular reaction. ...

Treatment

Chloroquine remains the treatment of choice for vivax malaria, except in Indonesia's Irian Jaya (Western New Guinea) region and the geographically contiguous Papua New Guinea, where chloroquine resistance is common (up to 20% resistance). When chloroquine resistance is common or when chloroquine is contraindicated, then artesunate is the drug of choice;^[1] mefloquine is a good alternative and in some countries is more readily available.^[2] Quinine may be used to treat vivax malaria but is associated with inferior outcomes. Eradication of the liver stages is performed by primaquine administration, after checking the patients G6PD status to reduce the risk of haemolysis. Chloroquine is a 4-aminoquinoline drug long used in the treatment or prevention of malaria. ... Map showing West New Guinea region. ... Artemisinin is a drug used to treat multi-drug resistant strains of falciparum malaria. ... Mefloquine is an orally administered antimalarial drug used as a prophylaxis against and treatment for malaria. ... Quinine is a natural white crystalline alkaloid having antipyretic, anti-malarial with analgesic and anti-inflammatory properties and a bitter taste. ...

References

1. ^ Pukrittayakamee S, et al. (2000). "Therapeutic responses to different antimalarial drugs in vivax malaria". Antimicrob Agents Chemother 44 (6): 1680–5. 
2. ^ Maguire JD, Krisin, Marwoto H, Richie TL, Fryauff DJ, Baird JK (2006). "Mefloquine is highly efficacious against chloroquine-resistant Plasmodium vivax malaria and Plasmodium falciparum malaria in Papua, Indonesia". Clin Infect Dis 42 (8): 1067–72.