DIAGNOSIS OF PLASMODIUM FALCIPARUM MALARIA

This method is based on the detection of a soluble P. falciparum antigen known as Histidine-Rich Protein 2 (HRP-2), which is found circulating in the blood in-patients with falciparum malaria.

The technique involves the use of a test strip, which contains antibodies to HRP-2. When a small quantity of blood (2-3 drops) is added to the test strip, followed by a detector reagent, if the patient is infected with P. falciparum, the HRP-2 antigen binds with the antibodies, resulting in the appearance of a coloured line across the test strip (see attached diagrams).




Advantages
• Simple to use - does not require microscopes or skilled technical staff
• Fast - can be read in less than 15 minutes
• Sensitive - detects as few as 10 parasites / l ml of blood
• Specific for P. falciparum
• Reliable
• Storage - may be stored at temperature upto 37 C; refrigeration is not necessary.

Disadvantages
• Expensive - about Rs. 100.00 per test
• Doesn’t detect any other malaria species
• Takes up to 14 days for a patient to revert to negativity after successful treatment.