Malaria Parasite


Published on

by Vencinth Consular Romano

  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Malaria Parasite

  1. 1. Malaria Parasites ( P. malariae, P. vivax, P. ovale P. falciparum) By: Vencinth Romano
  2. 2. INTRODUCTION The term malaria was derived from the Latin words “mala aria or bad air”, denoting the diseases association with the bad smelling air coming from stagnant water, a favorite breeding sight of the mosquitoes that harbor the malaria parasite. Malaria is a disease of antiquity. It is characterized by intermittent chills, fever and sweating, anemia & splenomegaly. It is caused by protozoan parasites of the genus Plasmodium which is transmitted to man when the parasite infective stages are inoculated by the mosquito during a blood meal.
  3. 3. FOUR MAIN TYPES OF MALARIA PARASITES 1.Plasmodium Plasmodium malariae 1881 - intermittent fever every 72 hrs. It is also known as Quartan Malaria. 2. vivax 1890 - intermittent fever every 48 hrs. It is also known as benign Tertian Malaria. 3. Plasmodium falciparum 1897 - intermittent fever every 36 - 48 hrs. It is also known as Malignant tertian Malaria 4. Plasmodium ovale 1922 - intermittent fever every 48 hrs. It is also known as Ovale tertian Malaria.
  4. 4. MORPHOLOGY 1. Morphological features of P. malariae All the asexual stages of the parasites may be observed in the peripheral blood. The infected RBCs are normal in size. In the trophozoite stage, the young forms are about 1/3 of the diameter of the RBC and have a peculiarly solid appearance. The developing trophozoites lacks vacuole is band-like in form and pigment granules are large, numerous and dark. There are 6-12 merozoites (usually 8) in the schizont stage. These merozoites are usually arranged peripherally around a centrally clumped pigment in a rosseste formation. The gametocytes are spherical or oval in normal sized RBCs. There are abundant prominent dark brown coarse pigment scattered inside the RBC. Vencious_25
  5. 5. Rings Trophozoite Schizont Gametocyte P.MALRIAE
  6. 6. 2. Morphological features of P. vivax All the asexual stages are also seen in the peripheral blood. The infected RBCs are enlarged and decolorized. Shuffner’s dots are prominent. The ring form or young trophozoite occupies 1/3 of the diameter of the RBC and usually has 1 chromatin dot. The rings are definite but the outlines are irregular. The developing and older trophozoites are large with very irregular pseudopodial processes of the cytoplasm. The Schizont usally contains about 16 merozoites. The gametocytes are spherical or ovoidal in shape in enlarged RBC; the Shuffner’s dots are prominent. Vencious_25
  7. 7. Trophozoite Gametocyte Schizont Rings P. vivax
  8. 8. 3. Morphological features of P. falciparum The infected RBC are not enlarged or discolored. The multiple infection of the RBC is common. Normally, only the ring form or young trophozoites and gametocytes are observed in the peripheral blood. The ring forms have delicate, thread-like line of cytoplasm. Some have double chromatin dots; some are found in the margin of the RBC called “applique or acole forms”. Also, characteristically, red cells maybe invaded by several rings, even up to 8. Schizonts are usually not found in the peripheral blood. When seen, the merozoites usually number 8-24. The gametocyte seen in the peripheral blood are crescent or sausage shaped. The gametocytes appear in peripheral circulation after 8-11 days after patency, then disappear after about three (3) months. Vencious_25
  9. 9. Trophozoite Schizont Gametocyte Ring P. falciparum
  10. 10. 4. Morphological features of P. ovale The infected RBC is somewhat larger than normal, oval in shape and usually with fringed or irregular edge. Schuffner’s dots appear very early even in older rings. All the stages are found in peripheral blood. The trophozoites comprise a single bead of chromatin connected by a ring of cytoplasm surrounding a vacoule. Merozoites which are 6-12 in number, may be arranged in rossete formation arround a mass of brown pigment granules. Gametocytes are rather large, round or oval bodies and occupy th whole of the enlarged infected red blood cell. Vencious_25
  11. 11. Rings Trophozoite Schizont Gametocyte P.OVALE
  12. 12. LIFE CYCLE (ASEXUAL PHASE & SEXUAL PHASE)In liver tissues : In RBC: merozoites invade RBC young trophozoite (rings) Pre-erythrocytic phase Exo-erythrocytic phase Develop in liver cells to pre- Reinvade liver cells . Merozoites Mature Erythrocytic schizonts Develop to secondary (Reinvade RBC) trophozoites Exo-erythrocytic schizonts Sporozoites invade liver Hypnozoites Mature Schizonts Early Schizonts parenchymal cells Merozoites Macrogametocytes -Microgametocyte Mosquito become infected - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Sporogony or Sexual cycle in the Anopheline Mosquito Mosquito Infects Man Female gametocyte mature (macrogametes) Sporozoites (in salivary gland) Male gametocyte extraflagellates (microgametes)
  13. 13. Characteristic of life cycle  Intermediate host : human  Final host : mosquito  Infective stage : sporozoite in mosquito merozoites in human  Infective way : mosquito bite skin of human  Parasitic position : liver and red blood cells
  14. 14. PATHOLOGY The multiple organ pathology in malaria is essentially due to tissue anoxia (lack of oxygen) and immunopathological mechanism. The severity of tissue anoxia in malaria cannot be adequately explained by obstruction of blood flow due to the clumping of the parasitized RBC alone. Another factor has been recently implicated. Stasis resulting from sympathetic constriction of renal cortical and portal circulation leads to cellular ischemia and damage to the endothelium. Both of these as well as the release of kinins increase o the endothelium water and protein molecules so that edema occurs outside the blood vessels, while hyperviscosity and more red blood cells clumping and obstruction to blood flow occur inside the blood vessels. The end result is tissue anoxia to which the vital organs(brain, adrenals, kidneys, heart and lungs) are the most sensitive. Other organs that become involved are GI, liver and placenta. Under certain circumstances, the immune response may itself result in disease. Such in the case in malaria, because some immunological factors have been implicated in several malaria complication – glomerulonephritis, topical splenomegaly syndrome (TSS), cerebral malaria and hemolytic anemia.
  15. 15. Laboratory diagnosis laboratory diagnosis of malaria is confirmed by the demonstration of malarial parasites in the blood film under microscopic examination (using thick and thin blood smears) (takendurind the febrile state & stained with Giemsa or Wright’s stain) Serology – Rapid Diagnostic Tests
  16. 16. EPIDEMIOLOGY Malaria is the leading cause of death and disease in many developing countries. According to the World Health Organization’s World Malaria Report 2011 and the Global Malaria Action Plan, 3.3 billion people worldwide live in areas at risk of malaria transmission in 106 countries and territories. In 2012 malaria led to 216 million clinical episodes, and 655,000 deaths. An estimated 91% of deaths in 2010 were in the African Region, followed by 6% in the South-East Asian Region and 3% in the Eastern Mediterranean Region (3%). 86% of all deaths worldwide are children.
  17. 17. CONT.... In the Philippines, all provinces with slow flowing, partly shaded, clean mountain streams are endimic because these are breeding sites of the pricipal mosquito vector, Anopheles flavirostris. There are three secondary vectors: Anopheles mangyanus, which is also a clean stream breeder, Anopheles balabacensis, which is a forest rain fall breeeder; and Anopheles litoralis, which thrive in brackish water. Anopheles maculatus also a stream breeder, is a potential vector. The annual parasite incidence is 15/1000, with 70% of cases caused by P. falciparum and 30% of these cases are caused by P. vivax. Transmission is perinial with two (2) peaks, one at the beginning and the other at the end of rainy season. P. Malariae is, with few exceptions, found only in Sulo Archipelago. Two indigenous case of P. ovale infections were reported from Palawan Island in 1967. Malaria can also be transmitted thru infected bood during blood transfussion and also by congenital infection. In these cases the Exo- erythrocytic phase in the liver is absent.
  18. 18. PREVENTION & CONTROL Chemoprophylaxis Using Mosquito Net Avoid outdoor night activities (particularly during the vector's peak biting hours from 9pm - 3am Using mosquito repellents/repellants Vector Control Reconstruction of environment: eradicate the breeding places of mosquitoes. House Spraying (using insecticides
  19. 19. TREATMENT Choloroquine is the drug of choice for treatment in area where there is a little or no parasites resistance to this drug. Sulfadoxine/pyrimethamine combination is used where there is high level of resistance to Choloroquine. In areas where there is resistance to both, Mefloquine or Mefloquine/ Sulfadoxine/pyrimethamine combination may be used. Primaquine is the only drug currently available for the radical treatment of relapsing vivax or ovale malaria.
  20. 20. • Thanks !  I love MPZC… Vencinth here!