2. Our case
• A 17-year-old women admitted to hospital after returning
from vacation in Malawi.
• She didn’t take preventing measures regarding malaria.
• 3 days after returning she had cold shiver, headache, dry
cough, lost weight and her stools became loose.
• Upon admission, she was ill, pale and slightly confused.
• Her lab test showed she had P. falciparum infection.
• She was treated with artemether and lumefantrine.
3. Learning objectives:
• Definition of malaria and types of malaria parasites.
• Epidemiology of malaria.
• Risk factor of malaria.
• Life cycle of malaria.
• Incubation period of the parasite.
• Pathophysiology of malaria.
• Signs and symptoms of malaria.
• Laboratory diagnosis of malaria.
• Treatment and prevention of malaria.
• Complication of malaria.
4. Definition of Malaria and type of
malaria parasite
Is an infection of liver and RBCs caused by
protozoan parasites of the genus plasmodium.
Malaria is caused by 5 species of plasmodium:
• P. falciparum (the most common and dangerous).
• P
. vivax.
• P
. ovale.
• P
. malaria.
• P
. knowlesi.
5. Epidemiology of malaria
• Malaria is widely distributed in tropics and subtropics of
Africa, Asia and Latin America.
• Malaria affecting 400 million people word-wide.
• Malaria causing 2 million death each year.
species Distribution
P.
falciparum
West, East and central
Africa, Middle East, Far
East, South America.
P. vivax India, North and East
Africa, Far East, South
America
P. ovale Tropical Africa, India, Far
East
P. malaria Tropical Africa.
6. What do you think about the
risk factor of malaria?
7. Risk factors of malaria
Living or traveling in a region where malaria is present.
Traveling to area where malaria is common:
- Without taking medicine to prevent malaria.
- Being outdoors, especially in rural areas.
- Not taking steps to protect yourself from mosquito bites.
Pregnant women.
Children under 5 years of age.
Patients with HIV/AIDS.
8. Life cycle of malaria
Microbiology 3th book by Richard A. Harvey.
10. Incubation period of the parasite
species Incubation period (Liver cycle)
P. falciparum 7-14 days
P. vivax 12-17 days ( with relapse up to 3 years)
P. ovale 9-18 days ( with relapse up to 20 years)
P. malaria 13-40 days.
11. Con…
• The time between the fever episodes can be
characteristics of the infecting plasmodium species.
species Duration of fever (erythrocytic cycle)
P. falciparum 36-48 h, Malignant tertian malaria.
P. vivax 48h, Benign tertian malaria.
P. ovale 48h, Ovale tertian malaria.
P. malaria 72h, Quartan malaria.
12. Pathophysiology of malaria
• Showers of new merozoites are released from the RBCs
at intervals of approximately 48h for P.vivax, P.ovale and
P.falciparum and 72h for P.malaria. The episodic shaking,
chills, and fever coincide with this release.
• The parasites destroy large numbers of infected RBC,
thereby causing a hemolytic anemia.
13. Pathophysiology of malaria
• A characteristic brown malaria pigment derived from
hemoglobin, called hematin is released from ruptured
RBCs and produces discoloration of the spleen, liver,
lymph nodes and bone marrow.
• Activation of defense mechanisms in the host leads to a
marked hyperplasia of mononuclear phagocytes,
producing massive splenomegaly and occasional
hepatomegaly.
14. What do you think about the signs
and the symptoms of malaria?
15. Signs and symptoms of malaria
• Cycles of shaking chills followed by fever and profuse sweating.
• Hemolytic anemia.
• Jaundice.
• Dark pigmented urine (blackwater fever)
• Stools became increasingly loose.
• Hepatomegaly.
• Splenomegaly.
• Headache.
• Dry cough.
• Lost weight.
16. Diagnosis of malaria
• 1) Medical history.
• 2) Physical examination.
• 3) Laboratory diagnosis:
Microscopy Immunological techniques Molecular
techniques
1- Films of blood (Thick
and thin blood smear
study).
1- Antibody-based
techniques(serologic tests):
• Indirect fluorescent antibody
test (IFAT)
• Enzyme- linked immunosorbent
assay (ELISA)
2- Antigen-based techniques
• Rapid Diagnostic Tests (RDTs)
Polymerase Chain
Reaction (PCR)
2- Quantitative Buffy
Coat (QBC) test.
17. P
. Falciparum P
. Vivax P
. Malaria P
. Ovate
Quinine, Mefloquin,
Sulfadoxine and
Pyrimethamine.
Chloroquine
With
primaquine.
Treatment of malaria
To treat Malaria we most understand 2 concept:
• The geographic pattern of susceptibility of P. Falciparum
to antimalarial drugs.
• The type of plasmodium species causing the infection.
Chloroquine-
sensetive
areas
Chloroquine
-resistant
areas
Chloroquine.
18. Prevention of malaria
1 Prevent mosquito bite by:
Covering the limbs.
Using insects repellents.
Sleeping under mosquito nets.
Stagnant water should be avoided.
2 Chemical prophylaxis for travelers:
When you traveling to area:
Without chloroquine resistance: chloroquine is used.
With chloroquine resistance: melfloquine or doxycycline
may be used.
19. Complication of malaria
species Major complication
P. falciparum Cerebral malaria, haemolytic anaemia
(blackwater fever), jaundice,
hypoglycaemia
P. vivax Relapse due to liver hypnozoites.
P. malaria Nephrotic syndrome
P. Ovate Relapse due to liver hypnozoites
21. Summary
• Malaria is an infection of liver and RBCs.
• Caused by 5 different species of plasmodium.
• Malaria is one of the most serious problems.
• Symptoms: Fever( which may be periodic), chills, sweeting,
hemolytic anemia and splenomegaly.
• Diagnosis is by seeing plasmodium in a peripheral blood
smear.
• Treatment and prophylaxis depend on the species and
drug sensitivity.
24. Reference
• The Merck Manual of Diagnosis & Therapy, page 1540.
• Medical Microbiology book Murray 7th, page 765.
• Clinical Microbiology made ridiculously simple book 3th
( p.240-244).
• Medical Microbiology made memorable (p.80).
• Microbiology Lippincott's Third Edition (P.221-222)
