A report on Malaria and Anopheles

Malaria parasite connecting to a red blood cell

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.

Anopheles larva from southern Germany, about 8 mm long

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.

Feeding position of an Anopheles larva (A), compared to that of a nonanopheline mosquito (B)

Electron micrograph of a Plasmodium falciparum-infected red blood cell (center), illustrating adhesion protein "knobs"

Resting positions of adult Anopheles (A, B), compared to a nonanopheline mosquito (C)

The blood film is the gold standard for malaria diagnosis.

Key to the morphology of female Anopheles

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.

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

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

About 460 species are recognised; while over 100 can transmit human malaria, only 30–40 commonly transmit parasites of the genus Plasmodium, which cause malaria in humans in endemic areas.

- Anopheles

It is spread exclusively through bites of infected Anopheles mosquitoes.

- Malaria

5 related topics with Alpha

Mosquito

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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").

Image of pitcher plant mosquito Wyeomyia smithii, showing segmentation and partial anatomy of circulatory system

An egg raft of a Culex species, partly broken, showing individual egg shapes

Adult yellow fever mosquito Aedes aegypti, typical of subfamily Culicinae. Note bushy antennae and longer palps of male on left vs. females at right.

Aedes aegypti, a common vector of dengue fever and yellow fever

$Here an Anopheles stephensi female is engorged with blood and beginning to pass unwanted liquid fractions of the blood to make room in its gut for more of the solid nutrients.$

Female Ochlerotatus notoscriptus feeding on a human arm, Tasmania, Australia

Anopheles albimanus mosquito feeding on a human arm – this mosquito is the sole vector of malaria, and mosquito control is a very effective way of reducing the incidence of malaria.

Mosquitofish Gambusia affinis, a natural mosquito predator

A warning sign about mosquitoes in Sodankylä, Finland

A still from Winsor McCay's pioneering 1912 animated film How a Mosquito Operates

In this way, mosquitoes are important vectors of parasitic diseases such as malaria and filariasis, and arboviral diseases such as yellow fever, Chikungunya, West Nile, dengue fever, and Zika.

Anopheles

Plasmodium falciparum

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Laveran's drawing of various stages of P. falciparum as seen on fresh blood (1880).

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)

Plasmodium falciparum is a unicellular protozoan parasite of humans, and the deadliest species of Plasmodium that causes malaria in humans.

The parasite is transmitted through the bite of a female Anopheles mosquito and causes the disease's most dangerous form, falciparum malaria.

Plasmodium

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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.

The ensuing destruction of host red blood cells can result in malaria.

Insect hosts are most frequently mosquitoes of the genera Culex and Anopheles.

A fish parasite, the isopod Cymothoa exigua, replacing the tongue of a Lithognathus

Parasitism

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Close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life.

Head (scolex) of tapeworm Taenia solium, an intestinal parasite, has hooks and suckers to attach to its host

The parasitic castrator Sacculina carcini (highlighted) attached to its crab host

Human head-lice are directly transmitted obligate ectoparasites

Clonorchis sinensis, the Chinese liver fluke, is trophically transmitted

The vector-transmitted protozoan endoparasite Trypanosoma among human red blood cells

Mosquitoes are micropredators, and important vectors of disease

Life cycle of Entamoeba histolytica, an anaerobic parasitic protozoan transmitted by the fecal–oral route

Cuscuta (a dodder), a stem holoparasite, on an acacia tree

The honey fungus, Armillaria mellea, is a parasite of trees, and a saprophyte feeding on the trees it has killed.

Borrelia burgdorferi, the bacterium that causes Lyme disease, is transmitted by Ixodes ticks.

Enterobacteria phage T4 is a bacteriophage virus. It infects its host, Escherichia coli, by injecting its DNA through its tail, which attaches to the bacterium's surface.

Restoration of a Tyrannosaurus with holes possibly caused by a Trichomonas-like parasite

Wolbachia bacteria within an insect cell

Biologists long suspected cospeciation of flamingos and ducks with their parasitic lice, which were similar in the two families. Cospeciation did occur, but it led to flamingos and grebes, with a later host switch of flamingo lice to ducks.

The protozoan Toxoplasma gondii facilitates its transmission by inducing behavioral changes in rats through infection of neurons in their central nervous system.

Trait loss: bedbug Cimex lectularius is flightless, like many insect ectoparasites.

The dry skin of vertebrates such as the short-horned lizard prevents the entry of many parasites.

Leaf spot on oak. The spread of the parasitic fungus is limited by defensive chemicals produced by the tree, resulting in circular patches of damaged tissue.

The rescuing from extinction of the California condor was a successful if very expensive project, but its ectoparasite, the louse Colpocephalum californici, was made extinct.

Parasites are distributed very unevenly among their hosts, most hosts having no parasites, and a few hosts harbouring most of the parasite population. This distribution makes sampling difficult and requires careful use of statistics.

A plate from Francesco Redi's Osservazioni intorno agli animali viventi che si trovano negli animali viventi (Observations on living animals found inside living animals), 1684

Ronald Ross won the 1902 Nobel Prize for showing that the malaria parasite is transmitted by mosquitoes. This 1897 notebook page records his first observations of the parasite in mosquitoes.

"An Old Parasite in a New Form": an 1881 Punch cartoon by Edward Linley Sambourne compares a crinoletta bustle to a parasitic insect's exoskeleton

Fictional parasitism: oil painting Parasites by Katrin Alvarez, 2011

Idiobiont parasitoid wasps immediately paralyse their hosts for their larvae (Pimplinae, pictured) to eat.

Koinobiont parasitoid wasps like this braconid lay their eggs inside their hosts, which continue to grow and moult.

Phorid fly (centre left) is laying eggs in the abdomen of a worker honey-bee, altering its behaviour.

A hyperparasitoid pteromalid wasp on the cocoons of its host, itself a parasitoid braconid wasp

The large blue butterfly is an ant mimic and social parasite.

In brood parasitism, the host raises the young of another species, here a cowbird's egg, that has been laid in its nest.

The great skua is a powerful kleptoparasite, relentlessly pursuing other seabirds until they disgorge their catches of food.

The male anglerfish Ceratias holboelli lives as a tiny sexual parasite permanently attached below the female's body.

Encarsia perplexa (centre), a parasitoid of citrus blackfly (lower left), is also an adelphoparasite, laying eggs in larvae of its own species

Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes.

At the same time, Giovanni Battista Grassi and others described the malaria parasite's life cycle stages in Anopheles mosquitoes.

Sterile insect technique

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Method of biological insect control, whereby overwhelming numbers of sterile insects are released into the wild.

The map shows the current (orange) and former (yellow) distribution area and the approximate seasonal spread of the screw-worm fly.

Anopheles mosquito – malaria vector, example Anopheles arabiensis.