14. Manual Processes

What is malaria caused by?

Plasmodium parasite.

How is malaria transmitted?

Through bites by the female Anopheles mosquito.

When should blood be collected for malaria testing?

During a fever spike.

What must be done to properly identify malaria species?

Ask pertinent information on travel to malarial hotspots.

Which anticoagulant is used for malaria blood samples?

EDTA.

What types of blood smears are made for malaria identification?

Thick and thin blood smears.

What is the purpose of thick blood smears?

Used for parasitemia count.

What is the purpose of thin blood smears?

Used for species identification and morphology.

What calculation is used to determine parasitemia?

%parasitemia = (parasitized RBC / total RBC) × 100.

What is the formula for calculating parasitemia level?

Example: 15 parasitized RBCs seen: (15 x 100) / 1000 = 1.5%.

What is the most deadly malaria species?

Plasmodium falciparum.

Name a non-deadly malaria species.

Plasmodium vivax.

What do rapid diagnostic tests detect?

Antigens from the malarial parasite.

What is a limitation of rapid diagnostic tests?

May not detect low parasitemia levels.

What type of blood cells is preferred by malaria parasites?

Young red blood cells (RBCs).

How are trophozoites characterized in P. falciparum?

Amoeboid in shape.

How do trophozoites appear in P. vivax?

Slightly enlarged, oval shape with tufted ends.

How do trophozoites of P. malariae present?

Pigment spreads inside the cytoplasm; band form may be seen.

What hematocrit technique uses a capillary tube?

Microhematocrit.

What is needed for the microhematocrit procedure?

Capillary tube, microcentrifuge, capillary sealant.

How long should the microhematocrit be spun in the centrifuge?

5 minutes.

Where is the RBC line positioned in microhematocrit readings?

At the bottom of the card.

What is one benefit of the microhematocrit technique?

It is a compact technique for measuring hematocrit.

What does PCR testing help detect in malaria?

Low parasitemia levels or mixed infections.

What is the advantage of PCR testing over other methods?

Highly sensitive.

What is the calculation to find total % parasitemia if 15 out of 1000 RBCs are infected?

1.5% parasitemia.

How many malaria species are listed in the document?

Five.

What does the term 'schizont' refer to in malaria?

A stage in the life cycle of the malaria parasite.

What characterizes the 'gametocyte' stage in malaria?

It is the stage that can infect mosquitoes.

How does P. ovale differ in its effect on RBCs compared to other species?

RBCs are slightly enlarged.

What type of malaria testing provides quick results to physicians?

Rapid diagnostic tests.

What are the key factors in diagnosing malaria?

Travel history, symptoms, and blood test results.

What do 'ring' structures indicate in malaria diagnosis?

An early stage of the malarial life cycle.

What should be included when collecting blood samples for malaria?

Patient travel history and symptoms.

What is the clinical significance of identifying P. falciparum?

It is the most deadly malaria species.

What happens to parasitized red cells in P. vivax?

They may show enlargement.

How are the stages of malarial invasion characterized?

By the type of red blood cells they invade.

What defines thick blood smears in malaria diagnostics?

Higher sensitivity for parasitemia.

What materials are needed for microhematocrit testing?

Capillary tubes, microcentrifuge, blood samples.

To perform a thick smear, what is essential about the blood sample?

It requires a higher volume of blood.

What does the term 'parasitized RBCs' signify?

Red blood cells that contain malaria parasites.