2. An ancient disease : substantial toll of human life and
sufferings
Originated from Italian word Mala (bad) and ayia(air)
Latin word : Marshy
So
, malaria : disease caused by heat humidity and marshy areas
1st discovered : Alphonse Laveran : 1880 in RBC of patient
(Algeria)
3. Transmitted by female Anopheles mosquito
Common insect borne infection
Most deadly vector borne disease in the world
Life threatening parasitic problem : global problem worldwide
40% of world’s population : (2.4) billion risk
400-900 million people are affected
6. P.vivax and P.falciparum : account 95% of infection
Some estimate : P.vivax : accounts 80% of infections : widely
distributed in tropics, subtropics and temperate zones
11. 1.Pre-erythrocytic Schizogony
1st stage of human cycle
Sporozoites : doesn’t directly enter into RBC : so k/as PES
occurs : inside parenchyma of cells
Fully developed schizont measures 42µm : contains large no of
merozoites
Smaller micromerozoites : enter into circulation : to start ES
Larger macromerozoites : Re-enter liver cells : to start Exo ES
Some sporozoites : remain dormant in liver : Hypnozoites : cause relapse
12. Duration of this phase :
P.falciparum : 6 days
P.vivax : 8 days
P.ovale : 9days
P. malariae :13-16days
13. 2. Erythrocytic schizogony
Infected liver ruptures : merozoites release : invade RBC’s
Parasite reside the RBC and passes through :
RBC Trophozoite Schizont Merozoite
P.vivax : greater tendency for younger erythrocytes and
reticulocytes
P.falciparum : any age
P.malariae : old
P.ovale : Young
14. Parasitised red cells : enlarged : cells mature with parasites :
show stippling(formation of small dot)
P.vivax : Schuffner’s dot
P.falciparum : Maurer’s dot (large red spots)
P.malariae : Ziemann’s dot (few tiny dots)
P.ovale : Schuffner’s dot
15. Trophozoite : Have active amoeboid
2 forms :
1. Ring form (early trophozoite)
Nucleus : thinner side of ring
2. Amoeboid form (late trophozoite)
Presence of pseudopodia
Contains malarial pigment
16. Schizont
Appears after a period of 36-40 hours
Full grown trophozoite : ready to divide
Round in shape
Lost all amoeboid activities
Nucleus is large and lie at periphery
2 form :
Immature schizont (Nucleus not divided)
Mature schizont : Nucleus divided
17. 3.Gametogony
After ES : some merozoites : give rise to gametocytes : sexual function
after leaving man host
Occurs inside capillaries of bone marrow and spleen
Mature gametocytes : appears in peripheral blood
Microgametocyte (male) : boarder, shorter with blunt ends
Macrogametocyte (female): longer, narrower, pointed ends
Changes in infected RBC’s (increase in size, pallor and different dots )
18. 4.Exo-erythrocytic Schizogony
Resembles PE form in morphology
Maintained upto 3 yrs and independent of ES
Short term and long term relapses (deteriorate after a period of
improvement)
Sporozoite PES Development of hypnozoites
ES EES
primary malaria Relapses
19. Relapse :
in case of P.vivax and P.ovale
due to the presence of hypnozoites
Recrudescence :
situation : RBC infection is not eliminated by the immune
system or by therapy
No of RBCs begin to increase again with subsequent clinical
symptoms
All species may cause
20. Sexual cycle of malarial parasite
Starts in human body : formation of gametocytes
Mosquito : blood meal : ingests both sexual and asexual forms
Asexual forms : digested
Sexual forms (gametocyte) : undergo further development
Blood of human carrier : must contain 12 gametocytes/mm3
21. No of female gametocytes more than male gametocytes
1st phase : mid-gut of stomach
Nucleus of each male gametocyte : 8 long flagellates(microgamete)
: highly motile
Process : observed : outside mosquito : thick film: exflagellation
Female gametocyte : don't divide : Macrogamete
Fertilizes : Zygote : motion less: later becomes motile : Ookinite
22. Ookinite : migrates to stomach wall : oocyst
Large no of sporozoites inside oocyst
When fully mature : oocyst ruptures : liberates sporozoites :
spread all parts : salivary gland
Ready to be transmitted : when it takes blood meal
23. MOT : bite of Anopheles mosquito
Extrinsic Incubation period :
different periods for the development of sexual cycle at given
temp
Varies : 8 to 21 days
Incubation period
P. falciparum : 12 days(9-14 days)
P. vivax : 14 days (8-17 days)
P. malariae : 28 days (18-40 days)
P. ovale :17 days (16-18days)
24. Main features : fever peaks followed by anemia and splenomegaly
Mild to severe and complicated :
According to species of parasite present
Patient’s state of immunity
Certain disease like : malnutrition and other disease
Severe in children and pregnancy
25. Main clinical features
1.Prodromal period
Malarial paroxysm :preceed by prodromal period
Non-specific symptoms : malaise, myalgia, headache and
fatigue
Some localized symptoms :chest pain, abdominal pain and
arthalgia
2. Malarial paroxysm
Classical manifestation of acute malaria
Characterised by fever chills and rigors
26. Primary fever
Typical attack 3 distinct stages: cold stage, hot stage and
sweating stage
a. Cold stage :
Onset with lassitude (lethargy), headache, nausea and chilly
sensations followed in an hour or so by rigors
b. Hot stage :
Patient feels hot and the skin is hot and dry to touch
Headache intense
Lasts for 30 min to 6 hrs
27. c. Sweating stage
Profuse sweating follows the hot stage
Continues for hour or so
Temp drops rapidly to normal
Skin is cool and moist
So, primary attack follows a febrile interval of 48-72hrs
28. 3.Anemia
Normocytic normochromic anemia
Severe in falciparum malaria
4. Hepatospleenomegaly
Spleen : palpable after 2nd weeks of fever
Severe in P.falciparum : so K/as malignat malaria
5. Malaria in pregnancy
Miscarriage or abortion
6.Malaria in children
More severe than as in adults
May develop convulsion (muscular contarction) during malarial
attack
Dehydration: as a result of vomiting and sweating.
30. 1.Black water fever
Repeated infection of P.falciparum: inadequately treated
with quinine
Massive hemolysis followed by fever and
haemoglobinuria(black coloured urine),hyperbilirubenemia
Complication : uraemia (blood poisoning), renal failure
,anemia, pigment calculi
31. 2.Pernicious anemia (Cerebral malaria or algid malaria)
May be different forms :
a. Pernicious malaria affecting nervous system : cerebral malaria
b. Pernicious malaria affecting GIT system (algid malaria)
c. Pernicious types affecting cardiovascular, respiratory and
genitourinary tract
32. Specimen :
Blood (before antimalarial drug)
Earlobe or finger in adults
Toe in infants
Collected : peak fever
More imp : frequently examination of blood smear
33. 1.Light microscopy
2. Fluorescence microscopy
3. Quantitative buffy coat
1.Light microscope
Blood smear
Gold standard method
Most commonly used
Depends upon : demonstration of parasite in stained PBS
Ring forms and gametocyte : commonly seen in PBS
34. 1.Thick smear
Smear preparation
Dehaemoglobinisation with d/w
Dried and stained with Romanowsky’s stain : Leishman stain.
Geimsa stain
Uses
To detect parasite
Demonstrating malarial pigment
35.
36. P. falciparum : (only ring and crescent form)
Many ring forms
Crescent forms gametocyte
Malarial pigments : inside the blood
P. vivax
Trophozoites, Schizont and Gametocytes can be seen in PBS
Ring form : nucleus more thicker
Gametocyte : spherical or globular
Schufnner’s dot
37.
38.
39.
40.
41. Thin smear
Rapidly dried
Fixed in alcohol and stained
Uses
Detecting parasites
Identify species
P. falciparum
Ring form alone or along with gametocytes
Multiple rings in individual RBC’s
Presence of Maurer’s dot
Banana shaped gametocytes