Malaria is a disease transmitted through mosquito bites in nature. Symptoms include chills, fever, sweating, and anemia. Severe cerebral malaria can be fatal. The four common strains of malarial parasites that infect humans are Plasmodium vivax, Plasmodium falciparum, Plasmodium ovale, and Plasmodium malariae. What are the commonly used diagnostic methods for malaria? Below are three common diagnostic methods for malaria.
Blood smear examination is the most commonly used method for malaria testing in the laboratory, and is also the “gold standard” recommended by the World Health Organization. Clinically, an anticoagulant tube (used for testing blood routine) is commonly used. 2-5 mL of blood is extracted from the peripheral vein of the patient, and a standard malaria blood smear is made. When the film is dry, it is stained with Giemsa and allowed to air-dry before microscopic examination for the presence of malarial parasites. The Malaria test strip is simple and intuitive to use, low-cost, and can be completed within 1 hour from film production to result reporting. It has high sensitivity, can distinguish the species and stages of the parasites, calculate parasite density, and can be used to guide treatment and prognosis, as well as for the diagnosis of other diseases such as hematological diseases or other blood parasitic pathogens.
The rapid diagnosis test of the Malaria test kit is an immunochromatographic gold method for detecting malarial parasite-specific antigens in whole blood samples. Its principle is based on the specificity of Plasmodium falciparum HRP2 (histidine-rich protein 2) and species-specific pLDH (parasitic lactate dehydrogenase) or pan-specific aldolase. It has a commercially available test kit that can detect the four common strains of malarial parasites. The operation is simple and convenient, similar to a clinical early pregnancy test, and does not require power, instruments, and other equipment. The entire process takes only 5-20 minutes to produce results.
The routine nucleic acid diagnostic detection methods for malaria mainly include Nest-PCR and real-time fluorescence quantitative PCR. The Nest-PCR method targets Plasmodium 18ssrRNA gene using species-specific primers for amplification and electrophoresis, which takes about 4 hours. The real-time fluorescence quantitative PCR method takes less time than Nest-PCR, and can produce results in about 2 hours, and can also dynamically record the entire amplification process.
The nucleic acid detection method is the basis for confirming and typing malaria diagnosis, but traditional blood smear examination and rapid diagnosis tests have irreplaceable advantages. All three methods also have their own limitations. Therefore, it is generally recommended that clinical laboratories with conditions should simultaneously use all three methods.
After learning about the common diagnostic methods for malaria, if you encounter friends who have traveled to malaria-endemic areas in Africa or Southeast Asia and have developed a fever due to mosquito bites, remember to remind them to go to the hospital or disease control center for malaria screening and testing!