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Malaria
or the symptoms of malaria have been noted for more than 4,000 yrs. The
name is derived from the Italian for bad air- mal’aria. By the 4th century BCE
malaria was widely recognized in Greece
and can be attributed to the decline of many rural and city-state
populations. The malaria parasite was discovered in 1880 and in 1897
Ronald Ross was first to demonstrate that mosquitoes could become infected with
malaria after feeding on an infected patient. This required that the
parasite have a sporogonic cycle. Shortly thereafter in 1899 the mode of
transmission was demonstrated when scientists showed that a mosquito that fed
on a patient positive for malaria could transmit the disease to a healthy
volunteer by feeding on them.
It is a vector borne disease, which is transmitted by
mosquitoes. This occurs when a mosquito feeds on an infected patient,
acquiring the parasite, which it can then transfer to another human. The
infected person will then test positive for malaria and will show signs of the
disease when the parasite has infected the liver and caused the cells to burst,
resulting in parasite throughout the bloodstream. It is during one of these
fever spells when the parasite can be easily found in the blood that another
mosquito can feed, acquire the parasite and then repeat the cycle.
Malaria can either be prevented, by not allowing the mosquito to infect the
human in the first place, or it can be treated once the person is already
infected, thus targeting the parasite.
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Outbreaks of malaria
are closely aligned with the breeding grounds of the vector, the Anopheles
mosquito. The Anopheles mosquito is a passive carrier of the
disease. It allows the detrimental parasite, Plasmodium, to undergo its
full life cycle and enter into the blood of the mosquito. Malaria can
only be transmitted in regions where the parasite can complete its life-cycle
before the mosquito dies of natural causes. Thus, malaria is not a
disease that can be transmitted directly from person to person, but requires
the mosquito intermediate.
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