MALARIA Flashcards
1
Q
cause
A
- protoctistan, plasmodium
2
Q
basic transmission
A
- female mosquitoes act as vectors when they pierce the skin to drink blood
3
Q
vector
A
an animal/insect/person that carries a disease and transmits it into another organism
4
Q
pandemic/endemic/epidemic? (3)
A
- endemic in some sub-tropical regions
- can become epidemic in wet season
- can be regarded as pandemic
5
Q
detailed transmission (10)
A
- mosquitoes take in blood from an infected person they take in gametocytes
- gametocytes produce zygotes
- zygotes develop into infective sporozoites
- sporozoites move from the mosquito’s gut to salivary gland
- when mosquito takes a meal, sporozoites in saliva are injected into human
- travel to the liver and reproduce asexually in the liver cells producing merozoites
- merozoites released into the blood and infect ed blood cells where they continue to reproduce
- red blood cells burst and release more merozoites that infect more red blood cells
- cycle continues, fever occurring when blood cells burst
- some merozoites become gametocytes
6
Q
treatment (2)
A
- drugs do not effect plasmodium when inside cells so only effective in blood
- current treatment is a combination of drugs as simultaneous mass-resistance is unlikely
7
Q
prevention
A
- no vaccine available bc it mutates frequently producing many antigenic types
- preventing mosquito bites
- controlling mosquitoes
8
Q
preventing mosquito bites (5)
A
- sleeping under nets, bc. mosquitoes feed between dusk/dawn
- nets treated with insecticide, to kill mosquitoes
- spray indoor walls with insecticide to kill mosquitoes when they rest after feeding
- drain/cover stagnant water, to prevent egg-laying
- film of oil on water, reduces surface tension so larvae cannot pierce the surface to get oxygen
9
Q
biological control of mosquitoes
A
- fish introduced into water to eat larvae
- infecting mosquitoes with wolbachia bacterium, bc it blocks plasmodium development
- sterilise male mosquitoes with x-rays, preventing offspring
