A malaria diagnosis should be considered in anyone with a fever who lives in or has travelled to a malaria endemic region.

Malaria diagnosis is usually made by examination of blood samples under the microscope to look for parasites. This method remains both more specific and sensitive than more sophisticated polymerase chain reaction (PCR)-based tests and other techniques.

In settings where laboratory facilities or capacity is limited, malaria diagnosis is often made simply on the basis of a patient having fever, and testing whether treatment resolves it.

Rapid diagnostic tests, such as dipstick antigen detection methods, are increasingly becoming available. Currently, these are more expensive than microscopy, but they could improve the ability to confirm a malaria diagnosis within 15 minutes in difficult field settings.