A report on Plasmodium falciparum and Artemisinin

Figure 1. Biosynthesis of Artemisinin
Laveran's drawing of various stages of P. falciparum as seen on fresh blood (1880).
Artemisia annua
Blood smear from a P. falciparum culture (K1 strain - asexual forms) - several red blood cells have ring stages inside them. Close to the center is a schizont and on the left a trophozoite.
Ring forms in red blood cells (Giemsa stain)
Life cycle of Plasmodium

Artemisinin and its semisynthetic derivatives are a group of drugs used in the treatment of malaria due to Plasmodium falciparum.

- Artemisinin

Tu Youyou discovered artemisinin in the 1970s from sweet wormwood (Artemisia annua).

- Plasmodium falciparum

6 related topics with Alpha

Overall
Malaria parasite connecting to a red blood cell

Malaria

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Mosquito-borne infectious disease that affects humans and other animals.

Mosquito-borne infectious disease that affects humans and other animals.

Malaria parasite connecting to a red blood cell
Main symptoms of malaria
The life cycle of malaria parasites. Sporozoites are introduced by a mosquito bite. They migrate to the liver, where they multiply into thousands of merozoites. The merozoites infect red blood cells and replicate, infecting more and more red blood cells. Some parasites form gametocytes, which are taken up by a mosquito, continuing the life cycle.
Micrograph of a placenta from a stillbirth due to maternal malaria. H&E stain. Red blood cells are anuclear; blue/black staining in bright red structures (red blood cells) indicate foreign nuclei from the parasites.
Electron micrograph of a Plasmodium falciparum-infected red blood cell (center), illustrating adhesion protein "knobs"
The blood film is the gold standard for malaria diagnosis.
Ring-forms and gametocytes of Plasmodium falciparum in human blood
An Anopheles stephensi mosquito shortly after obtaining blood from a human (the droplet of blood is expelled as a surplus). This mosquito is a vector of malaria, and mosquito control is an effective way of reducing its incidence.
Man spraying kerosene oil in standing water, Panama Canal Zone, 1912
Walls where indoor residual spraying of DDT has been applied. The mosquitoes remain on the wall until they fall down dead on the floor.
A mosquito net in use.
An advertisement for quinine as a malaria treatment from 1927.
Deaths due to malaria per million persons in 2012
Past and current malaria prevalence in 2009
Ancient malaria oocysts preserved in Dominican amber
British doctor Ronald Ross received the Nobel Prize for Physiology or Medicine in 1902 for his work on malaria.
Chinese medical researcher Tu Youyou received the Nobel Prize for Physiology or Medicine in 2015 for her work on the antimalarial drug artemisinin.
Artemisia annua, source of the antimalarial drug artemisinin
U.S. Marines with malaria in a field hospital on Guadalcanal, October 1942
Members of the Malaria Commission of the League of Nations collecting larvae on the Danube delta, 1929
1962 Pakistani postage stamp promoting malaria eradication program
Malaria clinic in Tanzania
Child with malaria in Ethiopia
World War II poster
Disability-adjusted life year for malaria per 100,000 inhabitants in 2004 no data <10 0–100 100–500 500–1000 1000–1500 1500–2000 2000–2500 2500–2750 2750–3000 3000–3250 3250–3500 ≥3500

Most deaths are caused by P. falciparum, whereas P. vivax, P. ovale, and P. malariae generally cause a milder form of malaria.

The recommended treatment for malaria is a combination of antimalarial medications that includes artemisinin.

Antimalarial medication

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Antimalarial medications or simply antimalarials are a type of antiparasitic chemical agent, often naturally derived, that can be used to treat or to prevent malaria, in the latter case, most often aiming at two susceptible target groups, young children and pregnant women.

Antimalarial medications or simply antimalarials are a type of antiparasitic chemical agent, often naturally derived, that can be used to treat or to prevent malaria, in the latter case, most often aiming at two susceptible target groups, young children and pregnant women.

Incidence and distribution of the disease ("malaria burden") is expected to remain high, globally, for many years to come; moreover, known antimalarial drugs have repeatedly been observed to elicit resistance in the malaria parasite—including for combination therapies featuring artemisinin, a drug of last resort, where resistance has now been observed in Southeast Asia.

Practice in treating cases of malaria is most often based on the concept of combination therapy (e.g., using agents such as artemether and lumefantrine against chloroquine-resistant Plasmodium falciparum infection), since this offers advantages including reduced risk of treatment failure, reduced risk of developed resistance, as well as the possibility of reduced side-effects.

Plasmodium

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Genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects.

Genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects.

Plasmodium is a eukaryote but with unusual features.
Life cycle of a species that infects humans
Ring forms of Plasmodium inside human red blood cells (Giemsa stain)
Sporozoites, one of several different forms of the parasite, from a mosquito
Oldest mosquito fossil with Plasmodium dominicana, 15-20 million year old
Many birds, from raptors to passerines like the red-whiskered bulbul (Pycnonotus jocosus), can carry malaria.
A clinic for treating human malaria in Tanzania
Over 3000 species of lizard, including the Carolina anole (Anolis carolinensis), carry some 90 kinds of malaria.
The mosquito Anopheles stephensi is among the blood-feeding insects that can be infected by a species of Plasmodium.

Over the course of the 20th century, many other species were discovered in various hosts and classified, including five species that regularly infect humans: P. vivax, P. falciparum, P. malariae, P. ovale, and P. knowlesi.

Resistance to quinine spurred the development of a broad array of antimalarial medications through the 20th century including chloroquine, proguanil, atovaquone, sulfadoxine/pyrimethamine, mefloquine, and artemisinin.

Artemisia annua

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Common type of wormwood native to temperate Asia, but naturalized in many countries including scattered parts of North America.

Common type of wormwood native to temperate Asia, but naturalized in many countries including scattered parts of North America.

Artemisia annua
Seeds

An extract of A. annua, called artemisinin (or artesunate), is a medication used to treat malaria.

Malaria is caused by apicomplexans, primarily Plasmodium falciparum, which largely reside in red blood cells and contain iron-rich heme-groups (in the form of hemozoin).

Quinine

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Medication used to treat malaria and babesiosis.

Medication used to treat malaria and babesiosis.

Tonic water, in normal light and ultraviolet "black light". The quinine content of tonic water causes it to fluoresce under black light.
Quinine biosynthesis
19th-century illustration of Cinchona calisaya

This includes the treatment of malaria due to Plasmodium falciparum that is resistant to chloroquine when artesunate is not available.

They recommend that it be used only when artemisinins are not available.

Artemether/lumefantrine

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Combination of the two medications artemether and lumefantrine.

Combination of the two medications artemether and lumefantrine.

It is used to treat malaria caused by Plasmodium falciparum that is not treatable with chloroquine.

In 2001, the first fixed dose artemisinin-based combination therapy to meet the World Health Organization's (WHO) pre-qualification criteria for efficacy, safety and quality was created.