Para - Malaria Flashcards
Describe the vector for Plasmodium species responsible for malaria.
The vector for Plasmodium species is the Anopheles mosquito.
Define the role of the Anopheles mosquito in the life cycle of Plasmodium.
The Anopheles mosquito is the definitive host for Plasmodium because it contains the sexual cycle of the parasite.
How many species of Plasmodium are mentioned in the content, and what are they?
Four species of Plasmodium are mentioned: Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium falciparum.
Explain the difference between the definitive host and the intermediate host in the context of malaria.
The definitive host, Anopheles mosquito, supports the sexual cycle of Plasmodium, while the intermediate host, humans, undergoes asexual cycles.
Duration of paroxysmal attack of each species
Plasmodium vivax causes Benign Tertian Malaria, Plasmodium ovale causes Ovale Tertian Malaria, Plasmodium malariae causes Quartan Malaria, and Plasmodium falciparum causes Malignant Tertian Malaria.
How does the life cycle of Plasmodium begin in humans?
The life cycle of Plasmodium begins in humans when the Anopheles mosquito injects sporozoites into the bloodstream.
Describe the habitat of Plasmodium within the human host.
Plasmodium initially resides temporarily inside liver cells and then inside red blood cells (RBCs) during its life cycle.
What is the significance of the chimpanzee in the context of Plasmodium species?
Chimpanzees serve as a reservoir host (RH) for P. malariae.
Explain the term ‘paroxysm’ in relation to malaria.
Paroxysm refers to the sudden recurrence or intensification of symptoms, such as fever, associated with malaria.
How many asexual cycles occur in the human host during the Plasmodium life cycle?
There are two asexual cycles that occur in the human host during the Plasmodium life cycle.
Describe the Exoerythrocytic Schizogony Cycle.
It occurs inside the liver where sporozoites enter the body through the saliva of a mosquito during a bite, leading to the formation of liver schizonts that contain merozoites.
How do merozoites invade red blood cells (RBCs)?
Merozoites are liberated from ruptured liver schizonts and invade RBCs, initiating the Erythrocytic schizogony cycle.
Define the Erythrocytic schizogony cycle.
Merozoites liberated from ruptured liver invade RBCs to become a ring, to a trophozoite, to an erythrocytic schizont containing merozoites.
Erythorcytic schizont ruptures liberating merozoites.
What happens to most merozoites after they are released from erythrocytic schizonts?
Most merozoites reinvade other RBCs and continue the schizogony cycle, while some form male microgametocytes and female macrogametocytes.
Explain the process of gametogony in the mosquito.
In the mosquito, male microgametocytes undergo reduction division to form male microgametes, while female macrogametocytes mature into female macrogametes.
How is a zygote formed in the mosquito’s gut?
Male microgametes fertilize female macrogametes in the lumen of the mosquito’s gut, resulting in the formation of a zygote.
Describe the role of the ookinete in the mosquito’s life cycle.
The ookinete penetrates the wall of the mosquito’s gut after fertilization, leading to the formation of an oocyst.
What occurs within the oocyst in the mosquito?
The oocyst contains sporocysts that produce sporozoites, which eventually rupture and are released into the salivary glands of the mosquito.
How do sporozoites enter a new host?
Sporozoites are introduced into a new host’s blood when the mosquito feeds again.
Describe the modes of infection for blood-transmitted malaria.
The modes of infection include the bite of an infected female Anopheles mosquito, blood transfusion, congenital malaria, and the use of contaminated syringes.
Define the infective stage of malaria when transmitted through a mosquito bite.
The infective stage of malaria transmitted through a mosquito bite is the sporozoite.
How does congenital malaria occur?
Congenital malaria occurs due to placental infarctions or when the umbilical cord is cut.
List the infective stages of blood-transmitted malaria.
The infective stages of blood-transmitted malaria are Ring, Trophozoite, Schizont, and Merozoites.
What is the shape and size of the sporozoite in malaria?
The sporozoite is fusiform or banana-shaped and measures 5-15 micrometers.
Explain the term ‘Transfusion Malaria’.
Transfusion Malaria refers to malaria transmitted through blood transfusions from an infected donor.
Identify the infective stage of Plasmodium in mosquitoes.
The infective stage of Plasmodium in mosquitoes is the gametocyte.
Do blood transfusions pose a risk for malaria transmission?
Yes, blood transfusions can pose a risk for malaria transmission if the blood is from an infected donor.
Describe hypnozoites in relation to Plasmodium vivax and ovale.
Hypnozoites are latent sporozoites that remain dormant inside the liver for years, leading to potential relapse of malaria.
Define the significance of stippling in infected red blood cells (RBCs).
Stippling refers to fine or coarse granules that appear in infected RBCs due to cytoplasmic damage caused by the growing parasite.
How do malarial pigments form in infected RBCs?
Malarial pigments, such as haematin granules, form inside the cytoplasm of the parasites due to the digestion of hemoglobin.
Explain the role of Schuffner’s dots in Plasmodium vivax and ovale.
Schuffner’s dots are fine stippling observed in infected RBCs specifically in Plasmodium vivax and ovale.
Describe the shape of infected RBCs in Plasmodium ovale.
In Plasmodium ovale, infected RBCs have a weak wall and acquire an oval shape.
What is responsible for the recurrence of symptoms in malaria due to hypnozoites?
Recurrence of symptoms occurs after cure due to the reactivation of hypnozoites in Plasmodium vivax and ovale.
How does Plasmodium falciparum affect the shape of infected RBCs?
In Plasmodium falciparum, infected RBCs may exhibit Maurer’s clefts and have a distinct shape compared to other species.
Define relapse in the context of malaria caused by Plasmodium vivax and ovale.
Relapse refers to the recurrence of malaria symptoms due to the reactivation of dormant hypnozoites in the liver.
Explain the difference in liver involvement between blood-transmitted malaria and other forms.
In blood-transmitted malaria, merozoites released from ruptured erythrocytic schizonts do not invade the liver, resulting in no liver affection and no relapse.
Describe the appearance of Ziemann’s dots in Plasmodium malariae and ovale.
Ziemann’s dots are specific stippling patterns observed in infected RBCs of Plasmodium malariae and ovale.
Describe the morphological differences between Plasmodium vivax and Plasmodium falciparum in terms of infected red blood cells (RBCs).
Plasmodium vivax fills 1/3 of the RBC and has a very thin rim of cytoplasm, while Plasmodium falciparum fills 1/6 of the RBC and has a vacuole.
How does the appearance of the early trophozoite stage differ between Plasmodium vivax and Plasmodium falciparum?
In Plasmodium vivax, the early trophozoite has a thin rim of cytoplasm and a single ring with 1-3 chromatin dots. In contrast, Plasmodium falciparum has a very thin rim of cytoplasm and 1-2 chromatin dots in the ring.
Define the characteristics of the late trophozoite stage in Plasmodium vivax compared to Plasmodium falciparum.
The late trophozoite of Plasmodium vivax has irregular, amoeboid cytoplasm and is not seen in peripheral blood, while Plasmodium falciparum fills the RBC and has compact cytoplasm.
What is the structure of the schizont stage in both Plasmodium vivax and Plasmodium falciparum?
Both Plasmodium vivax and Plasmodium falciparum schizonts contain 12-24 merozoites and clumped malarial pigments, and neither is seen in peripheral blood.
How do the male microgametocytes of Plasmodium vivax and Plasmodium falciparum differ in appearance?
The male microgametocyte of Plasmodium vivax is rounded with diffuse chromatin, while that of Plasmodium falciparum is crescentic with diffuse chromatin.
Describe the female macrogametocyte characteristics in Plasmodium vivax versus Plasmodium falciparum.
The female macrogametocyte of Plasmodium vivax is rounded with compact chromatin, whereas in Plasmodium falciparum, it is crescentic with compact chromatin.
What changes occur in the infected RBCs of Plasmodium vivax and Plasmodium falciparum?
Infected RBCs in Plasmodium vivax become enlarged, while those in Plasmodium falciparum remain unchanged.
Define Schuffner’s dots and Maurer’s clefts in the context of Plasmodium species.
Schuffner’s dots are stippling seen in Plasmodium vivax, while Maurer’s clefts are associated with Plasmodium falciparum.
Describe the cause of a malarial paroxysmal attack.
A malarial paroxysmal attack is caused by the rupture of erythrocytic schizonts, leading to the release of toxins, pigments, debris, and pyrogens.
Define Tertian Malaria and its occurrence in different Plasmodium species.
Tertian Malaria occurs every third day and is associated with Plasmodium vivax and Plasmodium falciparum.