1. Mrs. Dalia Kamal Eldien MSC in Microbiology
Blood Coccida Malaria
Mrs. Dalia Kamal Eldien
MSC in Microbiology
lecture NO-10-

2. Objectives Revision of the protozoa classification
Characteristics of plasmodium
Taxonomy of plasmodium
Main species of plasmodium
Distribution of the parasite over the world
Life cycle
Clinical features and pathology of malaria
Laboratory diagnosis

3. Entamoeba histolytica Acanthamoeba species Naegleria species
The basic generally accepted practical classification of the medically important parasitic protozoa
Amoebae
Entamoeba histolytica
Acanthamoeba species
Naegleria species
Flagellates
Giardia lamblia
Trichomonas vaginalis
Trypanosoma species
Leishmania species
Ciliates
Balantidium coli
Coccidia
Blood coccidia:
Plasmodium species
Tissue coccidia:
Toxoplasma gondii
Intestinal coccidia:
Isospora belli
Cryptosporidium parvum
Cyclospora cayetanensis
Microsporidia
Encephalitozoon species
Enterocytozoon species

4. General characteristic of the Coccidia
1. Locomotive organelles absent, the flagella present only in male gamete. 2. Life cycles are complex, with well-developed a sexual(which produce merozoites) and sexual stages (which produce oocysts) . 3. Microscopic, spore-forming parasite, sporozoa produce special spore like cells called sporozoites. 4. It obligate intracellular parasites belonging to the apicomplexan class.

5. Blood coccidia –Plasmodium-
Malaria is Potentially life-threatening disease caused by Plasmodium protozoa, transmitted to humans from infected female Anopheles mosquitoes
Malaria parasites are intracellular protozoa.
The Plasmodium parasite infect the red blood cells
Malaria is mainly a disease of tropical and subtropical areas.
Malaria is preventable and curable disease
If left untreated, the development of severe complications can cause death

6. Malaria Have Indirect life cycle.
Anopheles mosquito is the definitive host (development of the parasite refer as sporogony).
Human is the intermediate host (development of the parasite refer as schizogony).

7. Taxonomy Kingdom Animalia Subkingdom Protozoa Phylum Apicomplexa
Class Sporozoasida
Order Eucoccidiorida
Family Plasmodiidae
Genus Plasmodium
Species falciparum,  malariae,  ovale,  vivax

8. Plasmodium species:
Plasmodium falciparum.
Plasmodium vivax.
Plasmodium ovale.
Plasmodium malariae.
Plasmodium knowlesi, has recently been identified as a clinically significant pathogen in humans in Southeast Asia
Among patients with malaria, 5-7% are infected with more than a single Plasmodium species.
P falciparum and P vivax are responsible for most new infections.
Each species has a defined area of endemicity, although geographic overlap is common.

9. Distribution Of Plasmodium falciparum

10. Distribution Of Plasmodium vivax

11. The vector

12. Mode of Transmission Mosquitoes bites Blood transfusions
Transplacental (from infected mother to her fetus)

13. Life cycle The malaria parasite life cycle involves two hosts
During a blood meal, a malaria-infected female Anopheles mosquito inoculates sporozoites into the human host
Sporozoites infect liver cells (hepatic schizogony) and mature into schizonts
which rupture and release merozoites
Merozoites leave the liver and infect red blood cells (erythrocytic schizogony)
The trophozoites (ring stage the feeding stage of a protozoan parasite )mature into schizonts or gametocyte

14. Life cycle The schizonts rupture releasing more merozoites
The gametocytes is sexual erythrocytic stages, wait for mosquito
Gametocytes ingested by mosquito.
Male and female gametes produce Zygote which is become an ookinete
The ookinete attach to the mosquito gut and give oocyst.
Mature oocyst ruptures and release the Sporozoites reach salivary glands of mosquito.

17. Clinical features and pathology of malaria
The characteristic feature of malaria is fever caused by the release of toxins (when erythrocytic schizonts rupture) which stimulate the secretion of cytokines from leucocytes and other cells.
Incubation period 6-19 days
The classical attack lasts 6-10 hours.
a cold stage (sensation of cold, shivering)
a hot stage (fever, headaches, joint & muscle pain vomiting; seizures in young children)
and finally a sweating stage (sweats, return to normal temperature, tiredness)

18. Symptoms
Headache
Back & joints pain
Vomiting & diarrhoea.
Anemia & jaundice
Splenomegaly.

19. Severe malaria manifests as follows:
Cerebral malaria: This feature is always caused by P falciparum infection, coma may occur.
Severe anemia
Renal failure: a rare complication of malarial infection.
Respiratory symptoms: Patients with malaria may develop metabolic acidosis and associated respiratory distress.
Black water fever; rare complication, occur due to rapid massive intravascular hemolysis of both parasitized & nonparasitized RBCs, haemoglobinaemia, haemoglobinuria& renal failure.

20. Laboratory diagnosis
The diagnosis of malaria is by: 1- Detecting and identifying malaria parasites microscopically in blood films. In most endemic areas, microscopic slide examination of peripheral blood remains the most widely used test as well as the gold standard for detecting malaria parasitemia. Microscopy is based on examination of both thick and thin films made from the same sample of peripheral blood. 2- Concentrating parasites in venous blood by centrifugation when they cannot be found in blood films. 3- Using a malaria rapid diagnostic test (RDT) to detect malaria antigen.

21. Malaria parasites in thick and thin blood films, although thick films are more sensitive for detecting the presence of malaria parasites, they are not very useful in speciating the parasites, which should be done using the thin films. The blood film can stain stains by:
● Field’s stain
● Giemsa stain
Results
Chromatin of parasite Dark red
Cytoplasm of parasite Blue
Schuffner’s dots Red
Red cells Grey to pale mauve

22. Trphozoite of plasmodium

23. Gametocyte of plasmodium

24. ????

25. p. falciparum Not in peripheral blood In peripheral
Blood, trophozoite& gametocyte

26. Gametocyte of p. falciparum

28. Rapid Diagnostic test
ParaSight F and ICT Malaria PF:
Helpful , not need microscope, have results that are easy to interpret
It depends on detection of P.falciparum histidine rich protein 2 (HRP-2)
Disadvantage is used for p. falciparum only
OptiMal test:
Detects plasmodium lactate dehydrogenase (pLDH),
Advantage that is used for all species

29. Rapid Diagnostic test