A new mutation allows Plasmodium falciparum to exit the liver without maturing into merozoites. What would be the immediate consequence?

Correct option is A

The correct answer is (a) Absence of RBC rupture and reduced clinical symptoms

Explanation:

• Plasmodium falciparum is the parasite responsible for the most severe form of malaria in humans. Normally, after being transmitted via the bite of an infected mosquito, the parasite enters the liver where it matures into merozoites, which are then released into the bloodstream to infect red blood cells (RBCs).
• If a mutation causes Plasmodium falciparum to exit the liver without maturing into merozoites, it would prevent the typical cycle of RBC rupture (which causes malaria symptoms such as fever, chills, and anemia).
• As a result, absence of RBC rupture would lead to reduced clinical symptoms, as the parasite would not reach the stage where it destroys RBCs, which is typically responsible for the primary symptoms of malaria.

Information Booster:

• The liver stage of the Plasmodium life cycle is crucial for the parasite's development before it moves into the erythrocytic stage (where it infects RBCs).
• The merozoites that mature in the liver are released into the bloodstream and invade RBCs, where they grow, divide, and ultimately cause the rupture of the RBCs, leading to the symptoms of malaria.
• A mutation that prevents the parasite from completing this cycle would likely result in a less severe or asymptomatic form of infection, reducing the typical clinical manifestations of malaria.

Additional Knowledge:
(b) Direct infection of alveoli: This is not a typical consequence for Plasmodium falciparum. The primary infection route is via RBCs, not the alveoli.
(c) Increased severity of disease: The mutation described would likely result in reduced disease severity, as it disrupts the typical RBC rupture cycle responsible for the symptoms of malaria.
(d) Immediate immune response and clearance: While the immune system would still respond to the parasite, the lack of RBC invasion and rupture would likely result in a less robust immune response since the usual symptoms that trigger immune reactions (e.g., RBC lysis) would be absent.