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When an infected anopheles mosquito bites someone, plasmodia enter the human's blood system along with the insect's saliva. At this stage, the parasites are known as sporozoites. They are the start of the asexual reproduction. |
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Reproduction in the Liver |
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It takes only 30-60 minutes for the sporozoites to travel to the liver and penetrate the cells there. At this point, the immune system can intervene by forming antibodies. |
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The sporozoites reproduce and change their form in the liver cells. Thousands of merozoites are formed. After one to two weeks, the liver cell bursts and washes the merozoites into the blood. |
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The sporozoites reproduce and change their form in the liver cells. Thousands of merozoites are formed. After one to two weeks, the liver cell bursts and washes the merozoites into the blood. |
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Reproduction in the Blood (1) |
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| The merozoites penetrate red blood cells to reproduce. |
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| Some 20 merozoites
grow in a red blood cell, which ultimately bursts under the pressure
of the parasites. The released merozoites can infect more blood cells. Infection and reproduction repeat a number of times, generally every two to three days. The immune defence can also react to merozoites. |
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Some 20 merozoites grow in a
red blood cell, which ultimately bursts under the pressure of the
parasites.
The released merozoites can infect more blood cells. Infection and reproduction repeat a number of times, generally every two to three days. The immune defence can also react to merozoites. |
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Reproduction in the Blood (2) |
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A part of the merozoites which infest red blood cells transform themselves there into female or male gametocytes. These are precursors of germ cells. This concludes the asexual reproduction of the plasmodia in humans. |
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Development in the Mosquito |
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The malaria parasites can develop further only if a female anopheles mosquito ingests female and male gametocytes together with the feast of blood. |
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The sexual reproduction begins with the fertilization. |
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A zygote forms which penetrates the intestinal wall. |
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A zygote forms which penetrates the intestinal wall. |
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After a number of intermediate stages, an oocyst filled with sporozoites is formed. When it breaks open, the sporozoites move to the saliva glands of the anopheles mosquito. |
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After a number of intermediate stages, an oocyst filled with sporozoites is formed. When it breaks open, the sporozoites move to the saliva glands of the anopheles mosquito. |
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This concludes the sexual reproduction. The malaria cycle begins anew at the next bite. |
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