FInal: Malaria Flashcards
What is the etymology of “malaria”?
Italian- malo: bad; aria: air
What % of the world is at risk of Malaria?
3.3 billion people (half the world’s population)
What % of worldwide deaths from Malaria occur in Africa?
90%
What population group experiences the most severe mortality rate and what % of deaths can be attributed to them?
90% of deaths occurred mostly among children under five years of age
Who was Charles Laveran?
- French Military Physician
- Observed Parasites in blood smear
- Discovered protozoa as cause of Malaria (1880)
- First time protozoa identified as disease agents
- Nobel Prize 1907
Who was Camillo Golgi?
Italian neurophysiologist
-Credited for having determined three forms of the parasite and the three types of fever. After prolonged studies he found a way of photographing the most characteristic phases in 1890
Who was Ronald Ross?
- Mosquitoes Transmit Malaria via Parasites (1897-1898)
- Malaria parasites transmitted from patients to mosquitoes (Anopheles)
- Parasites in body of female
- Infected Mosquito bites a healthy person
- inoculated - disease develops
What are the species of malaria parasite that can infect humans?
1) Plasmodium vivax (tertian)
2) Plasmodium ovale (tertian)
3) Plasmodium malariae (quartan)
4) Plasmodium knowlesi (?)
5) Plasmodium falciparum (tertian)
What is the most widespread form of malaria?
Plasmodium vivax
What is the most virulent form of malaria?
Plasmodium falciparum
What is the animal origin of malaria?
Chipanzee (Pan troglodytes schweinfurthii subspecies)
What is the vector for malaria?
Female Anopheline mosquito
Explain the life cycle of malaria:
1) A female Anopheles mosquito carrying malaria-causing parasites feeds on a human and injects the parasites in the form of sporozoites into the bloodstream
2) The sporozoites travel to the liver and invade liver cells
3) Over 5-16 days, the sporozoites grow, divide, and produce tens of thousands of haploid forms, called merozoites, per liver cell
4) The merozoites exit the liver cells and re-enter the bloodstream, beginning a cycle of invasion of red blood cells, asexual replication, and release of newly formed merozoites from the red blood cells repeatedly over 1-3 days
5) Some of the merozoite-infected blood cells leave the cycle of asexual multiplication. Instead of replicating, the merozoites in these cells develop into sexual forms of the parasite, called male and female gametocytes, that circulate in the bloodstream.
6) When a mosquito bites an infected human, it ingests the gametocytes. In the mosquito gut, the infected human blood cells burst, releasing the gametocytes, which develop further into mature sex cells called gametes. Male and female gametes fuse to form diploid zygotes, which develop into actively moving ookinetes that burrow into the mosquito midgut wall and form oocysts.
7) Growth and division of each oocyst produces thousands of active haploid forms called sporozoites. After 8-15 days, the oocyst bursts, releasing sporozoites into the body cavity of the mosquito, from which they travel to and invade the mosquito salivary glands
What are some possible complications of Plasmodium falciparum infection?
Brain infection (cerebritis), destruction of blood cells (hemolytic anemia), kidney failure, liver failure, meningitis, respiratory failure from fluid in lungs ( pulmonary edema), rupture of the spleen (hemorrhage)
What events lead to the first attempt to eradicate malaria?
- Early successes in mosquito control (Panama Canal)
- Effective interventions, chloroquine (prevents development of parasites in blood) and dichlorodiphenyltrichloroethane (DDT) available after WWII
- Availability of good diagnosis with microscopy
- 8th World Health Assembly launches Global Eradication Campaign (1955)
