''Plasmodium silvaticum'' is a parasite of the genus ''
Plasmodium
''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a blood-feeding insect host which then injects parasites into a vert ...
'' subgenus ''
Plasmodium
''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a blood-feeding insect host which then injects parasites into a vert ...
''.
Like all ''Plasmodium'' species, ''P. silvaticum'' has both
vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
and
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
hosts. The vertebrate hosts for this parasite are
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s.
Description
The parasite was first described by Garnham ''et al'' in 1972.
[Garnham PCC, Rajapaksa N, Peters W, Killick-Kendrick R (1972) Malaria parasites of the orang-utan ('']Pongo pygmaeus
The Bornean orangutan (''Pongo pygmaeus'') is a species of orangutan endemic to the island of Borneo. Together with the Sumatran orangutan (''Pongo abelii'') and Tapanuli orangutan (''Pongo tapanuliensis''), it belongs to the only genus of grea ...
''). Ann. Trop. Med. Parasitol. 66:287–94
It is a member of the vivax group and closely resembles the other members of this group.
Geographical occurrence
This species is found in
Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
.
Vectors
Vectors are ''
Anopheles balabacensis
''Anopheles balabacensis'' is a species of mosquito in the Culicidae
Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning "gnat"). The word "mosq ...
'', ''
Anopheles maculatus
''Anopheles'' () is a genus of mosquito first described and named by J. W. Meigen in 1818. About 460 species are recognised; while over 100 can transmit human malaria, only 30–40 commonly transmit parasites of the genus ''Plasmodium'', which c ...
'' and ''
Anopheles sundaicus''.
Clinical features and host pathology
The parasite has an approximately 48-hour life cycle and gives rise to a tertian fever. The disease itself appears to be mild with little overt pathology.
Its prevalence varies considerably: Wolfe ''et al''
[Wolfe ND, Escalante AA, Karesh WB, Kilbourn A, Spielman A, Lal AA. (1998) Wild primate populations in emerging infectious disease research: the missing link. Emerg. Infect. Dis. 4:14958.] found the highest ''Plasmodium'' spp. prevalence to be 93.5% (29/31) in captive animals but 11.6% (5/43) in wild orangutans. Despite the apparent lack of pathology, a study of the population genetics of the alpha 2 haemoglobin suggested that this parasite (or others like it) has had a significant selective effect on the orangutan genome.
[Steiper ME, Wolfe ND, Karesh WB, Kilbourn AM, Bosi EJ, Ruvolo M. (2005) The population genetics of the alpha-2 globin locus of orangutans (''Pongo pygmaeus'') J. Mol. Evol. 60(3):400-408]
It can be transmitted both by blood inoculation and by
sporozoite inoculation into splenectomized
chimpanzee
The chimpanzee (''Pan troglodytes''), also known as simply the chimp, is a species of great ape native to the forest and savannah of tropical Africa. It has four confirmed subspecies and a fifth proposed subspecies. When its close relative th ...
s.
References
silvaticum
{{plasmodium-stub