Testing for Dormant Malaria

QUESTION

When malaria is dormant in the body can it be detected in a blood test?

ANSWER

Not directly, no. A normal malaria blood test consists of a thick or thin smear, which is often stained and then looked at under a microscope; with these tests, you would not be able to see any sign of the malaria which is lying dormant in the liver. However, there is another type of blood test, known as serology, which looks for the body’s antibodies against malaria. These are proteins produced by the immune system when the patient becomes infected with malaria. These antibodies are specific to the type of malaria the person was infected with, and can persist for many months and even years. As such, if a patient was infected with one of the types of malaria which can become dormant (i.e. P. vivax and P. ovale), a serology test might be able to tell whether the patient had ever been infected with one of these two types, and then suggest that they might continue to have a dormant infection.