Malaria is not passed directly from person to person. It is transmitted by the bite of an infected female Anopheles mosquito, which needs a blood meal to develop her eggs. Male mosquitoes feed on nectar and do not transmit malaria.Infection of the human
1. When an infected mosquito bites, it injects saliva containing sporozoites into the blood.
2. Within about 30 minutes the sporozoites reach the liver and enter liver cells.
3. In each liver cell a sporozoite divides asexually many times, producing thousands of merozoites. After one to two weeks the liver cell bursts, releasing them into the blood.
4. Merozoites invade red blood cells, feed on haemoglobin and divide asexually again. The red blood cells burst, releasing more merozoites that infect new red blood cells. In P. falciparum and P. vivax this cycle takes about 48 hours.
5. Some merozoites develop into male and female gametocytes.Infection of the mosquito
6. A mosquito biting an infected person takes up gametocytes. In the mosquito's gut they form gametes, which fuse to form a zygote.
7. The zygote burrows into the gut wall and forms an oocyst, which releases sporozoites. These migrate to the salivary glands, ready to be injected at the next bite.
Less commonly, malaria is spread by blood transfusions, shared needles, or from mother to baby across the placenta, because these transfer infected red blood cells.
1. When an infected mosquito bites, it injects saliva containing sporozoites into the blood.
2. Within about 30 minutes the sporozoites reach the liver and enter liver cells.
3. In each liver cell a sporozoite divides asexually many times, producing thousands of merozoites. After one to two weeks the liver cell bursts, releasing them into the blood.
4. Merozoites invade red blood cells, feed on haemoglobin and divide asexually again. The red blood cells burst, releasing more merozoites that infect new red blood cells. In P. falciparum and P. vivax this cycle takes about 48 hours.
5. Some merozoites develop into male and female gametocytes.Infection of the mosquito
6. A mosquito biting an infected person takes up gametocytes. In the mosquito's gut they form gametes, which fuse to form a zygote.
7. The zygote burrows into the gut wall and forms an oocyst, which releases sporozoites. These migrate to the salivary glands, ready to be injected at the next bite.
Less commonly, malaria is spread by blood transfusions, shared needles, or from mother to baby across the placenta, because these transfer infected red blood cells.