Table 1 Advantages and disadvantages of parasitological diagnosis

Diagnosis based on clinical features alone has very low specificity and results in over-treatment

Parasitological diagnosis has low specificity

Improved patient care in parasite-positive patients

In a patient with fever, the presence of parasites neither reliably confirms malaria as the cause of the fever, nor excludes the possibility of other diseases

Identification of parasite-negative patients in whom another diagnosis must be sought

Other diagnoses should be sought in all patients, irrespective of the presence of malaria parasites

Prevention of unnecessary use of anti-malarials, reducing frequency of adverse effects especially in those who do not need the medicines, and drug pressure selecting for resistant parasites

Clinicians often prescribe anti-malarials even for patients with a negative test. Prescribing anti-malarials to parasite-negative patients will not increase selection pressure for new drug resistant mutations.

Improved malaria case detection and reporting

Some "cases" detected in high-transmission areas are incidental carriers of malaria parasites, presenting with another disease

Confirmation of treatment failures

RDTs cannot confirm treatment failures. It is only possible to do this with microscopy.