Malaria Parasites PDF

***[Malaria parasites]*** It is blood protozoan parasites, also it is an intermittent fever caused by protozoan parasite that invade red blood cells. Malaria means :- Male : Bad Area : Air Means bad atmosphere transmitted by inhalation. **[*Classification* :-]** Class: sporozoa Subclass: coc...

***[Malaria parasites]*** It is blood protozoan parasites, also it is an intermittent fever caused by protozoan parasite that invade red blood cells. Malaria means :- Male : Bad Area : Air Means bad atmosphere transmitted by inhalation. **[*Classification* :-]** Class: sporozoa Subclass: coccidian Family: Plasmodiidea Genus: Plasmodium Speacies: Falciprum Vivax Ovale Malarei ***[Plasmodium falciprum]*** Known as malignant tertian malaria ( Mt ) malaria. It is the most serious species, it is wide distributed up to 80% of malaria cases. It is malignant because it affect all ages of RBCs old and young. ***[Distribution:-]*** Found mainly in hot and humid regions in Africa, South America, India , Bangladesh, Pakistan. ***[Transmission :-]*** **- [ ]**By female anopheles mosquitoes 2-Blood donors (by needle). 3-Rarely congenital transmission (occur when mother with low immunity). ***[Life cycle :-]*** Sporozoite is an infective stage which injected by female anopheles mosquitoes when it take blood meal. Human act as intermediate host, while anopheles acts as a definitive host. ***[Life cycle in human :]**-* After inoculation of sporozoite, they are circulating in the blood for 1hr, then inter the liver cells (hepatocyte cell). In the liver cells sporozoite multiply and develop into schizont kown as:- Pre- erythrocytic schizont (PE). Take about 5-7 days to develop schizont in liver, it contain 30/000 merozoites. When schizont mature the liver cell rupture, merozoites come out in the blood, merozoite to complete cycle enter to the red blood cells (erythrocytes). Merozoites bind to specific protein found on the membrane of the red blood consider as receptors. Erythrocytic cycle take about 24- 36 hrs in P.f. Inside the red cells merozoites develop into trophozoite by forming a vacuole in the membrane of red blood cells, the trophozoite feed on Hb of RBCs, hemozoin is the pigment produced as the end product of Hb breakdown. When trophozoite is fully developed it is nucleus start to divide, this process called schizogony. P.f schizont contains (8-32) merozoites, schizont rupture from RBC so merozoite, toxins and pigments release in the plasma, causing fever, malaria attach. The incubation Merozoites invade new red cells, then develop into trophozoite, then schizont, casing further red cells destruction. In P.f one cell may contain more than one trophozoite (ring stage). After several erythrocytic cycles some merozoites invade red cell followed sexual development and give Gametocyte. Gametocytes not active stage, no feed, their presence in the blood means in active infection, and it is source of infection. Cycle to complete, gametocyte must be taken up by female anopheles mosquito, if not taken it will be die. ***[Life cycle in anopheles mosquito :-]*** The gametocyte differentiate into male and female inside anopheles stomach , both gametes fertilize together, the male nucleus fuse into female nucleus to give zygote , which is develop into motile ookinite, which is develop into oocyst which contain large number of sporozoites. When sporozoite mature it leaves oocyst and go to salivary glands, and be ready to infect. The development of P.f in mosquito (sporogony) takes 9-10 days. ***[Clinical features:-]*** ***[The general symptoms are:]*** 1-Fever 2-Cold 3-Headach 4-Vomiting 5-Sweat 6-Diarrhea ***[Complication of plasmodium falciprum:-]*** *P.f* is most complicated malaria species for human. 1-Erythrocytic shizogony takes place deep in capillaries of organs such as: brain, spleen, lung, intestine, bone marrow, heart. 2-Infected Red cells adhere together and lining in capillaries wall lead to blocking on capillaries of internal organs lead to congestion, hypoxia. 3-Cerebral malaria (CM):- 4-Black water fever:- There is massive haemolysis of infected and non infected red cells lead to hemoglobin. Urine appears dark red to brown -- black. 5-Anaemia:- Due to destruction of large number if infected RBCs. ***[Plasmodium vivax]*** Known as begin tertian malaria, found in tropical and sub tropical area, also in temperate area, Africa, Asia, south America. ***[Transmission:- ]*** Same way of *P.falciprum* by anopheles mosquitoes. ***[Life cycle:-]*** Same cycle except in liver cells some of sporozoites become dormant called Hypnozoites, they activated during 6-12 month up to 3 years cause Relapse fever. When they activate again they develop into pre erythrocytic schizont, which contain about 10,000 merozoites. *P*.*vivax* affects young RBCs only. The erythrocytic schizont contain up to 24merozoites. Then complete cycle same like falciprum. ***[Clinical features:-]*** 1-Fever 2-Cold 3-Vomiting 4-Nausea 5-Sweet ***[Complication:-]*** Enlargement of spleen Anemia Relapsing fever (in this case parasite is not found in the blood film). ***[Plasmodium oval]*** Known as tertian malaria. ***[Distribution:-]*** Found in tropical and sub tropical countries. ***[Transmission:-]*** Similar to other plasmodium species. ***[Life cycle:-]*** It is resembled to vivax in life cycle, the differences only in prerythrocytic schizont it contain 15,000merozoites, while erythrocytic cycle contain up to 10merozoites. It affects young RBCs. ***[Plasmodium malarei]*** Known as quart am malaria, it is less prevalence than P.f and P.v. ***[Distribution:-]*** Found in tropical and sub tropical area, Africa, India and Malaysia. ***[Transmission:-]*** Same way of Plasmodium species. ***[Life cycle:-]*** Same cycle the pre erythrocytic schizont contain about 15,000merozoites while the erythrocytic schizont contain about 10-12merozoites. *P*.*malarei* affect old RBCs only Here in p. m there is attack due to small number of infected RBCs in internal organs known as Recrudescence. ***[Prevention and control:-]*** 1-Void mosquitoes bite by:- Using bed net Wearing protective clothes (long). Using oil to kill mosquitoes in the water Using drugs Treat active infection Follow up treatment Destroy adult mosquitoes by spray Using chemicals Health education. ***[Diagnosis:- ]*** 1-Examination of blood thin and thick (Gold slandered techniques) blood films 2-Concentration techniques (by using hematocrite concentration technique). ***[3-Serological test:-]*** **[ICT (Immune chromatography test):-]** It is rapid test, Ag/Ab reaction **[4-Elisa (enzyme linkage immune sourbance assay).]** The main disadvantages of serology tests, that the parasite Ags (Histidine rich Protein2 and Parasite Lactate dehydrogenase PLDH) the remain in circulation even after clearance of the parasites for 2-3weeks, these give false Positive results which require un necessary teartment. **[5-PCR (polymerase chain reaction).]** Use for Research purpose ***[Natural immunity to malaria]*** People who are naturally resist malaria:- **1- Sickle cell anemia:-** Here HbSs found in the RBCs and its not suitable for malaria parasite. **2- HbF:-** This type of Hb found only in New borne, so it interferes with metabolism of Plasmodium parasites **3- Glycose-6-Phspate dehydrogenate deficiency:-** People deficiencies of G-6-PDD are resistant to Plasmodium **4-Duffy blood group:-** Consider as receptor on the RBCs, it facilitate penetration of Plasmodium to the cell, Black peoples Lack this receptors so they are naturally resistant. **5- Ovalocytosis (Elliptical):-** Oval shape of RBCs will not helped Plasmodium to enter inside. ***[Highly Susceptible People with Plasmodium:-]*** 1- Pregnant women:- Here schizogony occurs in Placenta. 2- Splenoctomized People (Removal of spleen). 3- Immune compromised People (HIV). ***[Types of Plasmodium treatment:-]*** 1- Chloroquine 2-meploquine 3- Sulphanogzine (Fansidar) 4- Primaquine 5- Quinine (in cerebral malaria) 6- Artimither 7-Artosunate