How is malaria transmitted?

I. Transmission through the bites of Anopheles mosquitoes

1. Transmission mechanism
   • The primary vector of malaria is the female Anopheles mosquito. When a female Anopheles mosquito bites a malaria – infected patient, it sucks the Plasmodium in the patient’s blood into its body. The Plasmodium undergoes a series of development and reproduction processes inside the mosquito, including gametogony and sporogony, etc., and forms infectious sporozoites.
   • When this Plasmodium – infected Anopheles mosquito bites a healthy person again, the sporozoites will enter the human body along with the mosquito’s saliva, resulting in the healthy person being infected with malaria.
2. Species and distribution of Anopheles mosquitoes
   • Different species of Anopheles mosquitoes transmit malaria in different regions. For example, in sub – Saharan Africa, Anopheles gambiae is one of the main vectors; in many malaria – endemic regions in Asia, Anopheles sinensis and Anopheles minimus play important roles in malaria transmission. These Anopheles mosquitoes usually inhabit near rice paddies, ponds, streams, and stagnant water around human – living environments.

II. Mother – to – child transmission

1. Congenital malaria
   • A pregnant woman with malaria can transmit Plasmodium to the fetus through the placenta, resulting in the fetus being born with malaria, a situation known as congenital malaria. In highly malaria – endemic areas, the incidence of congenital malaria is relatively high.
   • Plasmodium can pass through the placental barrier and enter the fetal blood – circulation system, infecting the fetus. After being infected with malaria, the fetus may experience a series of adverse consequences such as premature birth, low birth weight, and anemia, which seriously affect the growth, development, and health of the fetus.

III. Transmission through blood transfusion

1. Plasmodium in blood
   • Malaria can also be contracted if blood containing Plasmodium is transfused. Although this situation is relatively rare, it is a transmission route that needs to be taken seriously in malaria – endemic areas or areas at risk of imported malaria.
   • Plasmodium can survive in human blood for a period of time. When blood with Plasmodium is transfused into a healthy person, the Plasmodium will start to reproduce in the new host’s body and trigger malaria symptoms. In some cases such as accidents and surgeries that require large – volume blood transfusions, if the screening for Plasmodium in blood is not strict, malaria transmission through blood transfusion may occur.