How is malaria primarily transmitted?

Malaria is an infectious disease transmitted by mosquitoes. Malaria is transmitted by mosquitoes sucking the blood of patients, which carries the virus. When the mosquitoes suck the blood of other people, they can transmit the virus to others. Therefore, everyone should pay attention to the environmental hygiene of their living spaces and reduce the presence of mosquitoes. Malaria can also be transmitted through blood transfusion, mother-to-child transmission, and contact with clothing contaminated with malaria.

1. Mosquito Transmission: Malaria is mainly transmitted through the bites of mosquitoes, specifically female mosquitoes. There are different species of mosquitoes, but only Anopheles mosquitoes can transmit malaria. The most important species for malaria transmission is Anopheles sinensis, which is the main vector for the transmission of tertian malaria in plain areas. In mountainous areas, malaria is mainly transmitted by Anopheles minimus. In hilly areas, Anopheles lesteri subsp. anthropophagus is an important vector. In the mountainous areas of Hainan Island, Anopheles dirus has been found to be the main vector for malaria transmission.

2. Blood Transmission: If the blood of a malaria patient is transfused to another person, it can also lead to transmission through blood transfusion.

3. Mother-to-Child Transmission: Mothers with malaria can also transmit the disease to their children through the placenta. This type of malaria acquired by the child is known as congenital malaria.

4. Susceptibility of the Population: The population is generally susceptible to malaria. Although there is a certain degree of immunity after infection, it is not long-lasting. There is no cross-immunity between different types of malaria. After repeated infections, symptoms may be lighter or even asymptomatic upon reinfection. However, individuals from non-endemic areas are often more susceptible to infection and may experience more severe symptoms.

5. Malaria Patients and Carriers: Malaria patients and carriers are the sources of malaria transmission. They are only infectious when there are mature male and female gametocytes in their peripheral blood. The emergence time, duration, and carrier rate of gametocytes in the peripheral blood vary depending on the species of Plasmodium. Relapse patients have mature gametocytes in their blood when symptoms appear. Mild patients and carriers in malaria-endemic areas may not have obvious clinical symptoms, but they still have gametocytes in their blood and can become sources of infection.