QUESTION

Is malaria infectious?

ANSWER

Yes, malaria is considered an infectious disease, though it is very rarely transmitted directly between people, and virtually all of the time must be transmitted via the bite of a mosquito (of the genus Anopheles).

Because part of the life cycle of malaria occurs in red blood cells in the human host, if sufficient amounts of blood are shared between people, for example during a blood transfusion, malaria can also pass between them this way, though screening measures reduce the likelihood of this occurring. Similarly, an earlier part of the life cycle occurs in the liver, so transplant of this organ can also result in transmission.

Finally, malaria is able to pass through the placenta, and so can be transmitted from a mother to her unborn child in this way, or also via blood during childbirth. When a baby contracts malaria from each mother, either via the placenta or during childbirth, it is known as “congenital” malaria.