Plasmodium Multiple Choice Question & Answers

Plasmodium

Question 1. True about peripheral blood smear of malaria are all except:

1. Single ring form P. vivax
2. Multiple ring from in P. falciparum
3. Enlarged erythrocytes in P. vivax
4. Enlarged erythrocytes in P. falciparum

Answer. (4) (Enlarged erythrocytes in P. falciparum)

• In P. falciparum infection, RBC is normal in size and shape.

Read And Learn More: Micro Biology And Immunology Multiple Choice Question And Answers

Question 2. True about peripheral blood smear of plasmodium vivax:

1. Single ring with cytoplasm condensed around in each erythrocyte
2. Mature/old erythrocytes are affected
3. Parasitized erythrocytes of the same size as normal erythrocytes
4. Only ring and gametocytes are seen

Answer. (1) (Single ring with cytoplasm condensed around in each erythrocyte)

• Single ring with cytoplasm condensed around in each erythrocyte- for P. vivax
• Mature/old erythrocytes affected- for P. malariae
• Parasitized erythrocytes of the same size as normal erythrocytes- for P. falciparum and P.malariae
• Only ring and gametocytes are seen- for P. falciparum

Question 3. Which is gametocidal for all species:

1. Quinine
2. Chloroquine
3. Primaquine
4. None

Answer. (3) (Primaquine)

• Primaquine is gametocidal to all species of Plasmodium, while artemisinin has weak lethal action to early stage but not to mature gametes.
• Proguanil or pyrimethamine inhibits the gamete in mosquitoes.

Question 4. A patient from northeastern states was diagnosed to have an infection with P. falciparum malaria is the most appropriate drug for this patient?

1. Artemether plus lumefantrine
2. Sulfadoxine plus pyrimethamine
3. Chloroquine
4. Mefloquine

Answer. (1) (Artemether plus lumefantrine)

• Treatment of falciparum malaria (NVBDCP guideline):,
• North-Eastern States: ACT-AL, i.e. co-formulated tablet of artemether and lumefantrine; plus Primaquine-aiming to kill gametocytes of P. falciparum.
• Other states: ACT-SP, i.e. artesunate plus sulfadoxine/pyrimethamine, plus Primaquine.

Question 5. The Plasmodium species known for relapse in malaria is:

1. P. falciparum and P. vivax
2. P. vivax and P. malaria
3. P. vivax and P. ovale
4. P. malariae and P. ovale

Answer. (3) (P. vivax and P. ovale)

Relapse is seen in P.vivax and P.ovale; whereas recrudescence is seen in P. falciparum and P. malariae.

Question 6. Ziemann dots:

1. Plasmodium vivax
2. Plasmodium falciparum
3. Plasmodium malariae
4. Plasmodium ovale

Answer. (3) (P. malariae)

• RBC Stippling: They are pink to red colored dots on the membrane of RBCs infected with
• Plasmodium help in protein transport from the parasite to the erythrocyte surface.
• These are called by various names.
• Plasmodium vivax- Schuffner’s dots
• Plasmodium falciparum- Maurer’s cleft
• Plasmodium malariae- Ziemann’s dots
• Plasmodium ovale- James’s dots.

Question 7. True about malaria is/are:

1. Gametocytes are infective to mosquito
2. Relapse can occur in P. vivax
3. Chloroquine-resistant malaria is prevalent in eastern India
4. Vector: female Culex mosquito
5. P. malariae has the largest distribution in the world

Answer. (1, 2, 3) (Gametocytes are infective to mosquitoes, Relapse can occur in P. vivax, and Chloroquine-resistant malaria is prevalent in eastern India)

• Gametocytes are an infective form to mosquito
• Relapse can occur in P. vivax and P. ovale
• Chloroquine-resistant malaria is prevalent in eastern Indian states such as Odisha, Chhattisgarh, Bihar, Jharkhand, and West Bengal.
• Vector: female Anopheles mosquito
• P. vivax has the largest distribution in the world, whereas in India P. falciparum and P.vivax are equally prevalent.

Question 8. Which of the following is a new Plasmodium falciparum vaccine strain?

1. PPV23
2. RTS, S/AS01
3. R14-4
4. NYVAC-PF01

Answer. (2) (RTS, S/AS01)

• RTS, S/AS01 is a recent malaria trial started in 2005 in AfricVaccine candidate consists of the repeat and T-cell epitope in the PfCSP (circumsporozoite protein of P. falciparum), hepatitis B surface antigen (HBsAg) and a chemical adjuvant (AS01) to boost the immune system response.

Question 9. A 15-year-old boy presented with fever and chills for 3 days. On examination he was found to have delayed skin pinch time and dry oral mucosa peripheral blood smear revealed the following picture. Identify the pathogen involved:

1. Plasmodium falciparum
2. Babesia
3. Plasmodium vivax
4. Plasmodium ovale

Answer. (1) (P. falciparum)

History of fever with and chills, along with peripheral blood smear showing multiple ring forms and double dot ring forms inside RBCs- Suggestive of falciparum malaria.

Question 10. Plasmodium knowlesi all true except:

1. Endemic in Africa
2. Transmitted by anopheles
3. Does not cause recurrent malaria
4. Mostly affects children

Answer. (1) (Endemic in Africa)

• Plasmodium knowlesi is absent in Africa may be because there are neither longtailed nor pig-tailed macaques (the reservoir hosts of P. knowlesi) in Africa, and many
• West Africans lack the Duffy antigen – a protein on the surface of the red blood cell that the parasite uses to invade.
• This parasite causes non-relapsing malaria due to a lack of hypnozoites in its exoerythrocytic stage.

Question 11. The characteristic morphological forms associated with P. falciparum is/are:

• RBC enlarged
• Ring-shaped gametocytes
• Crescent shape gametocytes
• Multiple rings trophozoite
• All developmental stages are not seen in peripheral smears

Answer. (3, 4, 5) (Crescent-shaped gametocytes, Multiple rings trophozoite, All developmental stages are not seen in peripheral smears)

• P. falciparum—RBC normal size, 3 types of ring forms are seen such as multiple ring forms, accolade form and double dot ring forms. Gametocytes are crescent-shaped.
• Most of the RBC cycle of P. falciparum occurs in deep vessels.

Question 12. The schematic image of peripheral blood smear belongs to which of the following Plasmodium species?

1. Plasmodium vivax
2. Plasmodium falciparum
3. Plasmodium ovale
4. Plasmodium malariae

Answer. (1) (Plasmodium vivax)

Features in favor of P. vivax include Enlarged RBC, enlarged ring form which turns amoeboid shape in the late trophozoite stage, and schizont containing 12–24 merozoites.

Question 13. Duffy antigen associated with:

• Plasmodium falciparum
• Plasmodium ovale
• Plasmodium malariae
• Plasmodium vivax

Answer. (4) (P. vivax)

Question 14. Why are schizont and late trophozoite stages of Plasmodium falciparum not seen in peripheral blood smear?

1. They are sequestered in the spleen
2. Due to adherence to the capillary endothelium, they are not seen in peripheral blood
3. Due to antigen-antibody reaction and removal, antibody-dependent cytotoxic killing
4. They are seen in mosquito blood

Answer. (2) (Due to adherence to the…)

• P. falciparum gets sequestrated by adhering to the endothelium of deep vessels. After the ring forms are formed, the remaining part of the RBC cycle of P. falciparum occurs in deep vessels (not in peripheral blood).
• This is the reason why schizont and late trophozoite stages are not seen in peripheral blood smears.

Question 15. Transfusion-associated malaria, the infective form is:

1. Trophozoite
2. Sporozoites
3. Female gametocyte
4. Male gametocyte

Answer. (1) (Trophozoite)

Question 16. In patient with Malaria, if fever has a periodicity of 72 hours, which one of the following is likely to be the causative agent?

• P. falciparum
• P. vivax
• P. ovale
• P. malariae

Answer. (4) (P. malariae)

• In, P. malariae the febrile paroxysm occurs every 72 hrs, for others it occurs every 48 hrs.

Question 17. A patient is suffering from high-grade fever with chill and rigor. Which of the following complications he may develop?

1. Renal failure
2. Black water fever
3. Meningitis

Answer. (2) (Blackwater water fever)

• Black water fever is characterized by sudden intravascular hemolysis followed by fever, hemoglobinuria, and dark urine.
• It occurs following quinine treatment to subjects previously infected with P. falciparum.

Question 18. Malaria recrudescence is due to:

1. Resistant to treatment
2. Relapse of infection
3. Relapse in vivax and ovale
4. Reappearance of sexual stage parasitemia after treatment

Answer. (1) (Resistant to treatment)

• Recrudescence is seen in P. falciparum and P. malariae infections.
• In falciparum malaria, it is due to the persistence of drug-resistant parasites following the treatment course.
• In P. malariae infection, long-term recrudescences are seen for as long as for 60 years, this is due to the long-term survival of erythrocytic stages at a low undetectable level in blood, but the cause is NOT identified.

Question 19. People with HLA type __________are protected from Plasmodium falciparum:

1. HLA-Bw53
2. HLA B27
3. HLA B1

Answer. (1) (HLA-Bw53)

HLA-Bw53 and haplotypes bearing DRW13.02 antigen and R111 gene are protected from cerebral malaria.

Question 20. All are strategies for rolling back malaria except:

1. Strengthening the health system
2. Use of insecticide-treated mosquito nets
3. Training the healthcare workers

Answer. (2) (Development…)

• Roll back malaria (RBM): Launched in 2000. Aim to reduce malaria cases by 50% by the end of 2010 and 75% by the end of 2015.
• In Sept 2008, RBM launched the ‘Global Malaria Action Plan’ that defines the steps to achieve the target.

Malaria control strategies

• Surveillance and case management
• Integrated vector management: Such as indoor residual spray, insecticide-treated bed nets, antilarval measures
• Epidemic preparedness and early response
• Supportive interventions
• Capacity building
• Behavior change communication.

Question 21. The life cycle of the Malarial parasite was discovered in female Anopheles mosquitoes by:

1. Ronald Ross
2. Paul Muller
3. Laveran
4. Pampanga

Answer. (1) (Ronald Ross)

• French army surgeon Alphonse Laveran (1880) was the first to discover the causative agent Plasmodium, in the RBC of a patient in Algeria.
• Golgi described the asexual cycle of the parasite in RBC.
• Sir Ronald Ross, in 1897 had described the sexual cycle of the parasite in female
• Anopheles mosquito in Secunderabad, India.

Question 22. Which type of malaria is associated with nephrotic syndrome and renal failure?

1. Falciparum
2. Vivax
3. Malariae
4. Ovale

Answer. (3) (P. malariae)

P. malariae is associated with nephrotic syndrome and renal failure.

Question 23. Features of Severe malaria are:

1. Cerebral feature
2. ↑ LDH
3. Severe anemia
4. ↓ Platelet count
5. Metabolic acidosis

Answer. (1, 3, 4, 5) (Cerebral feature, Severe anemia, Low Platelet count, Metabolic acidosis)

Question 24. Which of the following acts as an intermediate host of the malaria parasite?

1. Culex
2. Female anopheles
3. Thromboculid mite
4. Human

Answer. (4) (Human)

1. Definite host (sexual cycle) of Plasmodium- Female anopheles mosquito,
2. Intermediate host (asexual cycle) of Plasmodium – man

Question 25. Schizonts are not seen in peripheral smears in which type of malaria?

1. P. vivax
2. P. falciparum
3. P. ovale
4. P. malariae

Answer. (2) (P. falciparum)

1. After the ring form is formed in the peripheral blood, the remaining of RBC cycle of P.falciparum occurs in the capillaries of brain and internal organiser.
   Hence, only the ring forms are found in the peripheral blood by microscopic examination but not late trophozoites and schizonts.
2. However, for other Plasmodium species, all erythrocytic stages occur in peripheral blood vessels.

Question 26. Cerebral malaria is caused by:

1. Plasmodium falciparum
2. Plasmodium ovale
3. Plasmodium vivax
4. Plasmodium malariae

Answer. (1) (Plasmodium falciparum)

• Cerebral malaria: Occurs due to plugging of brain capillaries by sequestration of parasitized RBCs leading to vascular occlusion and cerebral anoxia.
• Sequestration: i.e. holding back of the parasite in the blood vessels of deep visceral organs like brain, kidney, etleads to vascular occlusion.
• Cytoadherence is mediated by a protein PfEmp (P. falciparum erythrocytic membrane protein) which is only expressed by P. falciparum not by any other speices.

Question 27. True about malaria epidemiology?

1. Extrinsic IP -0–14 days
2. In India: common from Jan to June
3. Man- definitive host
4. Rare in urban
5. Mosquito-definitive host

Answer. (5) (Mosquito-definitive host)

Question 28. Which of the following is detected in peripheral blood smear?

1. Malaria
2. Toxoplasma
3. Babesia
4. Brucella
5. Filaria

Answer. (1, 2, 3, 4) (Malaria, Toxoplasma, Babesia and Filaria)

• Parasites detectable in blood smear
• Plasmodium spp in RBCs
• Toxoplasma- Tachyzoites
• Filarial microfilaria
• Trypanosoma spp.: Trypomastigotes
• Leishmania amastigotes in macrophages
• Babesia- in RBC

Question 29. All are factors for Resurgence of malaria except:

1. Vector resistance
2. Host resistance
3. Use of bed nets
4. Mutation in parasite

Answer. (3) (Use of bed nets)

• Multiple factors responsible for the resurgence of malaria:
• Development of resistance of vector to insecticides
• Development of drug resistance to malarial parasites due to mutation
• Multiple water-logging areas, lead to increased mosquito breeding
• Personal protective measures such as protective clothing, usage of mosquito bed nets or mosquito repellents are factors involved in the control of malaria outbreaks and not reasons for resurgence.

Question 30. Infective form of mosquito in Plasmodium falciparum is:

• Merozoites
• Sporozoites
• Gametocytes
• Trophozoites

Answer. (3) (Gametocytes)

• The infective form of the parasites to humans- Sporozoites.
• Mature gametocytes are infective form to the female Anopheline mosquitoes.

Question 31. Malarial parasite – which statement is false regarding communicability:

1. The gametocytes appear in blood 4–6 days after a sexual phase in P. vivax
2. The gametocytes appear in blood 10–12 days after a sexual phase in P. falciparum
3. The number of gametocytes increases in blood with time
4. The number of gametocytes increases by 1000 times

Answer. (3) (The number of gametocytes increases in blood with time)

• ‘Malaria is communicable as long as mature, viable gametocytes exist in the circulating blood in sufficient density to infect vector mosquitoes.’
• RG interval (time interval between appearance of ring form & gametocyte):
• In vivax infections, – 4–5 days, In falciparum infections -10-12 days
• In P. falciparum, sine the RBC cycle takes place in the vessels of internal organs, hence gametocyte takes time to come to the peripheral blood.
• Gametocytes are numerous during early stages (may exceed 1,000 per cubic mm of blood”) and do not increase in blood with time.

Question 32. Babesiosis is most commonly transmitted by:

1. Pigs
2. Rats
3. Sandfly
4. Ticks

Answer. (4) (ticks)

Babesiosis is most commonly transmitted by deer tick (hard tick) Ixodes scapularis.

Question 33. Identify the vector involved in the spread of the disease, whose peripheral smear is as given:

1. Ixodid tick
2. Anopheles
3. Louse
4. Sandfly

Answer. (1) (Ixodid tick)

• The figure shows the ring form in tetrad inside This form is called as Maltese cross form; a characteristic feature seen in infected RBCs for patients with Babesiosis. Babesia is transmitted by ticks (Ixodes scapularis).

Question 34. The gold standard test for Babesia:

1. Giemsa stain
2. Culture
3. PCR
4. Antibody detection

Answer. (1) (Giemsa stain)

• The gold standard test for most of all hemoparasites is stained peripheral smear. By this method, direct parasitological diagnosis can be done as well as parasite density and response to treatment can be monitored.
• Demonstration of 2 or 4 rings inside the RBCs (called as maltese cross forms) in the Geimsa stained thick and thin blood smear is the diagnostic feature.

Question 35. The Maltese cross is a characteristic feature of:

1. Cryptococcus neoformans
2. Babesia microtia
3. Blastomycosis
4. Penicillium Marini

Answer. (2) (Babesia microtia)

• Ring forms are arranged in tetrads – k/a Maltese cross appearance, Pathognomonic for babesiosis
• Sporozoites of Babesia enter into RBCs where they transform into trophozoites and then multiply asexually by budding giving rise to two or four daughter pear-shaped trophozoites (ring forms in tetrad called Maltese cross form) arranged inside RBCs.

Question 36. True about Babesiosis:

1. Caused by Babesia microtia
2. Resides in RBC
3. Resides in WBC
4. Chloroquine is the treatment of choice

Answer. (1, 2) (caused by Babesia microti and Resides in RBC)

• Intraerythrocytic protozoa
• Tick-borne malaria-like illness in animal
• Zoonotic: Opportunistic to human
• Species: microtia, bovis, versus
• Treatment of choice for Babesiosis: Clindamycin with oral quinine and atovaquone and azithromycin.