Gametocyte

Development

Main article: Gametogenesis

The development of gametogonia to primary gametocytes is called gametocytogenesis. The further development of primary gametocytes to secondary gametocytes is a part of gametidogenesis. Gametogenesis is the formation or production of gametes (taking place during meiosis). The development and maturation of sex cells also takes place during meiosis. Gametogenesis is also the process of formation in male and female gametes that occur in the gonads (ovary and testis). Both male and female produce gametes. Male gametocytes are called spermatocytes and female gametocytes are called oocytes. The term gametocyte is also used, for example, when talking about gametocytes of species like Plasmodium falciparum or Plasmodium vivax, which transmit malaria.

Malaria

Main article: Plasmodium#Life cycle, Apicomplexan life cycle

Male and female gametocytes are the components of the malaria parasite life cycle which are taken up from an infected host bloodstream by mosquitoes and thus mediate disease transmission. These gamete precursors are quite distinct from their asexual blood stage counterparts and this is reflected in their distinct patterns of gene expression, cellular development, and metabolism.

''Plasmodium falciparum''

Main article: Plasmodium falciparum

Mature macrogametocytes are female and mature microgametocytes are male. In P. falciparum, gametocytes are produced from asexual stages. All the gametocytes produced from one sexually committed schizont are of the same sex, suggesting that sex is determined at the very beginning of sexual development. However, gametocyte sex can only be microscopically differentiated from stage III and onward. They are crescent- or sausage- shaped.

''Plasmodium vivax''

Main article: Plasmodium vivax

Plasmodium vivax is a protozoal parasite transmitted to humans through the bite of infected mosquitoes, and is the cause of one of the most common[[File:Plasmodium vivax 01.png|thumb|Plasmodium vivax]] forms of malaria. Gametocyte carriage is essential for malaria transmission and endemicity of disease; thereby it is a target for malaria control strategies. Malaria-infected individuals may harbour gametocytes below the microscopic detection threshold that can be detected by reverse transcription polymerase chain reaction targeting gametocyte-specific mRNA. Although it is not one of the most dangerous forms, it affects many people annually, and can be somewhat resistant to drugs that are typically used to treat malaria. Once contracted, it can remain in the liver for years if left untreated with the appropriate medications. Given that the condition often occurs in poorer parts of the world, these medications are not always available, and some people continue to experience the effects of Plasmodium vivax for years. These infections take their toll on poor countries in other ways because many hospitalizations are due to initial symptoms of malaria and are costly. When people are first affected by Plasmodium vivax, they frequently show symptoms of high fever, chills, fatigue and profuse sweating. These symptoms often last for a period of about two to three days, but the process may be complicated if a person has additional illnesses. Other symptoms include vomiting, muscle aches, dizziness or a fever that comes and goes. After this primary infection, the disease can go dormant, but the symptoms may return regularly and other conditions like jaundice can develop because Plasmodium vivax establishes itself in the liver. There is no vaccine for Plasmodium vivax, though people who travel to areas with high malaria incidence may receive treatment for it, which is administration of a 14-day course of the drugs chloroquine and primaquine.

References

References

1. (10 June 2012). "Simultaneous detection of Plasmodium vivax and Plasmodium falciparum gametocytes in clinical isolates by multiplex-nested RT-PCR". Malaria Journal.
2. (February 2004). "Gametocitos de Plasmodium vivax y Plasmodium falciparum: etapas relegadas en el desarrollo de vacunas". Salud Pública de México.
3. "Plasmodium falciparum".
4. http://www.dpd.cdc.gov/dpdx/HTML/Frames/M-R/Malaria/falciparum/body_malariadffalcgame.htm {{Webarchive. link. (2013-03-09 {{full citation needed). (November 2020)
5. (14 January 2024). "What is Plasmodium Vivax? (With pictures)".