Malaria Test

To detect the parasite and diagnose malaria, your healthcare provider would take a thorough medical history to rule out the other diseases with similar sign and symptoms.

Some common signs and symptoms that are seen in malaria patients are as follows:

• Fever with chills
• Sweating
• Headache
• Malaise
• Nausea
• Vomiting
• Diarrhoea
• Muscle pain

The clinical findings in malaria caused by P. falciparum are more severe and striking. It includes mental confusion, seizures, severe anaemia, respiratory difficulties and coma. In addition to malaria test, your doctor will also suggest a blood count.

No special preparation is needed for this test.

For this test, smears are prepared using a very small quantity of blood. Typically, a technician will prick your middle or forefinger with a lancet. The first drop of blood is wiped away, and the next drop is collected on a clean slide. The slides are further subjected to analysis.

Two types of blood smears based on thickness are prepared – thick and thin smears. This is the ‘gold standard’ test for detection and identification of malaria and gives the number of malaria parasites present in the blood smear. It is also used to calculate the number of infected RBCs and determine the extent of infection (parasite load). Thick smears give better results than thin smears.

Another blood sample is collected for additional tests mentioned below:

• Rapid diagnostic test: In this test, malarial antigens are detected in a person’s blood, which is usually taken with the help of a finger stick. It is also known as dipstick tests. They allow faster diagnosis and treatment.
• Molecular test: A polymerase chain reaction (PCR) is used to detect parasite DNA, which is amplified using a PCR machine. It is used in cases where different species are causing the infection and helps confirm the diagnosis where there is a lack of training and experience in the identification of malaria using other tests.
• Serology test: This test detects the antibodies produced in body against malaria parasite. It does not detect an acute infection but can detect a previous exposure.
• Susceptibility test: Since some malarial parasites have become resistant to anti-malarial drugs in the course of time, this test is used to determine the vulnerability of the parasite to a drug in an infected person. It is done by allowing the blood samples to grow in the presence of varying amounts of a drug and then observing the effect of the said drug on the growth of the parasite.

• Thick and thin blood smears: A smear with several infected RBCs indicates the presence of malaria parasite.
• Rapid diagnostic tests (antigen testing): A colour change in the testing strip is indicative of infection.
• Molecular tests: A positive PCR result indicates the presence of the parasite in blood.
• Antibody tests (serology): A positive antibody test signifies active response of the body against malarial infection.
• Susceptibility testing: If the growth of the parasite is visualised using a PCR test it indicates susceptibility to drugs.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational perspective and is in no way a substitute for medical advice from a qualified doctor.