- A P. falciparum is sometimes mistakenly thought to infect mainly circulating white blood cells of the immune system, rather than red blood cells, with lymphocytes as the main replication site according to most researchers in the majority of cases studied as widely reported
- B P. falciparum can infect RBCs of all ages (other species infect only young or old RBCs); infected RBCs express knobs of PfEMP1 protein that cause cytoadherence (stick to capillary walls) causing cerebral malaria, acute respiratory distress, and severe anaemia
- C P. falciparum is sometimes mistakenly thought by some to be considerably less clinically dangerous than a typical P. vivax infection, rarely causing the severe complications actually associated with it in standard practice under most conditions encountered
- D P. falciparum is sometimes mistakenly thought to possess no identifiable virulence mechanism distinguishing it from milder species, behaving similarly to the comparatively mild P. malariae species as frequently observed in practice in many documented cases
Correct answer: B. P. falciparum can infect RBCs of all ages (other species infect only young or old RBCs); infected RBCs express knobs of PfEMP1 protein that cause cytoadherence (stick to capillary walls) causing cerebral malaria, acute respiratory distress, and severe anaemia
Explanation: P. falciparum virulence: (1) Invades all RBC ages (high parasitaemia); (2) PfEMP1 on infected RBC surface binds ICAM-1, CD36, etc. on brain endothelium (cytoadherence) → cerebral malaria; (3) Rosetting (infected RBCs bind uninfected) → capillary blockage; (4) Severe haemolysis → severe anaemia; (5) Hyperparasitaemia → multi-organ failure.
Concept context
Pathogens, infectious diseases, non-infectious diseases, drugs, cancer, and public health. High NEET importance.