Charles Louis Alphonse
Laveran, Patrick Manson,
Ronald Ross
parasitology
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Malarial parasite
- Ronald Ross found the eggs of the parasite
- in the stomach wall of a specific species of mosquito
- and showed that they got there by feeding on the blood
- of a man with malaria.
- Alphonse Laveran had already, in 1880,
- discovered the malarial parasite,
- and Patrick Manson had suggested, in 1894,
- that malaria was transmitted by mosquitoes.
Life cycle
- A female mosquito of the species Anopheles,
- to get protein to produce her eggs,
- sucks human blood.
- To reduce clotting and constriction of your blood vessels,
- the mosquito injects her saliva,
- infected with sporozoites, beneath your skin,
- from where the sporozoites migrate into your bloodstream.
- The sporozoites collect in your liver
- where they invade cells and set up homes,
- transform into a rounded form,
- and mature into schizonts containing many merozoites.
- Merosomes bud off the infected liver cells
- and these lodge in capillaries of the lungs
- where they disintegrate, releasing thousands of merozoites,
- which invade red blood cells.
- In red blood cells, the merozoites
- transform into ring-shaped and trophozoite forms
- and they divide several times into new merozoites
- that escape and invade other red blood cells.
- Some merozoites get into your bone marrow,
- change into male or female gametocytes,
- then freely circulate in your blood,
- which the female mosquito sucks up.
- In the mosquito’s midgut,
- the gametocytes change into gametes,
- fertilize each oher, become diploid zygotes,
- and transform into invasive ookinetes that escape the gut.
- Outside the gut, they invade cells and set up homes
- where they divide and produce thousands of sporozoites.
- The sporozoites migrate to the salivary glands
- from where they are injected into their next host.
A bad thing happens
- Mosquitoes suck
- as if there were good and bad.
- You do not like the parasite
- and neither does the mosquito.
- It is unfortunate that humans
- make such good hosts for this worm.
Ronald Ross studied malaria at a hospital in Calcutta India from 1882 to 1899. In 1897, he contracted malaria, was transferred to a medical school in Secunderabad, and there he discovered the plasmodium parasite in Anopheles mosquitoes.
See also in The book of science:
Readings on wikipedia: