SPOROZOA
Malaria and Babesiosis refers to the disease process resulting from the infections of parasites belonging to the
phylum Apicomplexa. Their respective genera are Plasmodium and Babesia. Both genera of parasites belong to
the class of parasites that have no obvious structures for the purpose of motility, known as Sporozoa. The most
clinically relevant organisms belonging to the genera of this discussion are Plasmodium vivax, Plasmodium
falciparum, Plasmodium ovale, Plasmodium malariae, Plasmodium knowlesi and Babesia microti.
A. Genus Plasmodium
(Include species causing malaria); these are the malarial parasites
Important species: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale
P. falciparum: Causes the most SERIOUS form of malaria because this species can infect almost half of the
total RBCs in the blood; 90% of malaria cases is due to this species
Plasmodium knowlesi – emerging Plasmodium species that can infect old world monkeys/macaques in SEA
countries including the Philippines
General characteristics common to all Plasmodium species
a. No definite organ for locomotion
b. Arthropod-transmitted (needs vector for transmission)
VECTOR: Female Anopheles Mosquitoes
- Male Anopheles is NOT capable of transmitting malaria since it is NOT blood feeder (does
not take blood meals)
c. MOT: Malarial Parasites, species under genus Plasmodium may be acquired thru SKIN
INOCULATION/BITES (this is the primary MOT)
Other MOT:
a. Blood transfusion – malaria maybe acquired thru transfusion of infected blood
b. Transplacental – vertical transmission from mother to fetus
d. Hosts: Requires 2 host to complete the cycle
DEFINITIVE HOST: Female Anopheles
INTERMEDIATE HOST: Man
e. Life cycle: consists of 2 phases/parts:
i. Sexual cycle aka SPOROGONY cycle – happens in the VECTOR
ii. Asexual cycle aka SCHIZOGONY cycle – happens in Man
Asexual cycle in Man has 2 parts:
i. Exo-erythrocytic cycle – part of the cycle that happens within LIVER/HEPATIC CELL
ii. Erythrocytic cycle – part of the cycle that happens within RBCs
o How long is the cycle in man (asexual cycle)? the length of the cycle varies according to species
o When Plasmodium parasites infect RBCs they alter/change RBC size. In addition, once they are within
RBCs, they consume hemoglobin so RBC stipplings may be found within infected RBCs.
, P. falciparum P. vivax P. ovale P. malariae P. knowlesi
Asexual cycle /
rupturing of infected 36hrs 48hrs 72hrs 24hrs
RBCs
Type of malaria Malignant tertian Benign Ovale malaria Quartan
malaria / Estivo tertian malaria
autumnal malaria malaria
Effect to RBC size No change in rbc Enlarged Enlarged RBC RBC reduced in
size RBC size
Stipplings are called Maurer’s dots Schuffer’s James dots Ziemann’s dots
granules
STAGES SEEN IN THE Only Ring and
BLOOD Gametocytes may All diagnostic stages
be found in the
blood
GAMETOCYTE Crescent/sausage or Round to oval shaped
banana shaped
RING FORM Aplique / accole Amoeboid Band form
TROPHOZOITE Forms
# OF MEROZOITES 6-12 average of 8-
PER INFECTED RBC 8-36 12-24 8, and arranged 10.
around a central Arranged in
block of pigment “rosette” or
“daisy” formation
Note: part of the asexual cycle in man is the RUPTURING of INFECTED RBC, and in the case of P. falciparum as
example, rupturing of RBC happens every 36 hrs. In P. vivax rupturing happens every 48 hrs.etc)
The primary mode of transmission is thru BITES/skin inoculation, and if Malaria is acquired thru bites BOTH exo-
erythrocytic and erythrocytic cycle happens in man. But if the mode of transmission is thru Blood transfusion or
transplacental, there is NO exo-erythrocytic cycle, in man it is only erythrocytic cycle
“Padaliin natin… pag kinagat ka ng infected Female anopheles, una syang pupunta sa liver/hepatic cell, part
ng life cycle ang pag rupture din ng infected liver cell, matapos mag rupture ang infected liver cell, ang next
naman na e-infect ay RBC.” – Dr. light
o Asexual/Schizogony cycle happens in Man (initially within liver cell, then within RBCs)
o Sexual/Sporogony cycle happens in the vector
o Infective stage of Plasmodium spp to Man: SPOROZOITES (given by vector to man)
o Infective stage of Plasmodium to Vector: Gametocyte (acquired by vector from an infected host)
Plasmodium species are INTRAERYTHROCYTIC parasites (they infect RBCs)
Plasmodium falciparum – infects RBCs of all ages (young & mature RBCs)
Plasmodium vivax and Plasmodium ovale – infect young/Immature/juvenile RBCs example of
which are the Reticulocytes
Plasmodium malariae – infects Mature/older RBCs
o All species can cause MALARIA
o Paroxysm is the characteristic /unique symptom of malaria characterized by chills fever and sweating.
This is the symptom regardless of malaria type.
Malaria and Babesiosis refers to the disease process resulting from the infections of parasites belonging to the
phylum Apicomplexa. Their respective genera are Plasmodium and Babesia. Both genera of parasites belong to
the class of parasites that have no obvious structures for the purpose of motility, known as Sporozoa. The most
clinically relevant organisms belonging to the genera of this discussion are Plasmodium vivax, Plasmodium
falciparum, Plasmodium ovale, Plasmodium malariae, Plasmodium knowlesi and Babesia microti.
A. Genus Plasmodium
(Include species causing malaria); these are the malarial parasites
Important species: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale
P. falciparum: Causes the most SERIOUS form of malaria because this species can infect almost half of the
total RBCs in the blood; 90% of malaria cases is due to this species
Plasmodium knowlesi – emerging Plasmodium species that can infect old world monkeys/macaques in SEA
countries including the Philippines
General characteristics common to all Plasmodium species
a. No definite organ for locomotion
b. Arthropod-transmitted (needs vector for transmission)
VECTOR: Female Anopheles Mosquitoes
- Male Anopheles is NOT capable of transmitting malaria since it is NOT blood feeder (does
not take blood meals)
c. MOT: Malarial Parasites, species under genus Plasmodium may be acquired thru SKIN
INOCULATION/BITES (this is the primary MOT)
Other MOT:
a. Blood transfusion – malaria maybe acquired thru transfusion of infected blood
b. Transplacental – vertical transmission from mother to fetus
d. Hosts: Requires 2 host to complete the cycle
DEFINITIVE HOST: Female Anopheles
INTERMEDIATE HOST: Man
e. Life cycle: consists of 2 phases/parts:
i. Sexual cycle aka SPOROGONY cycle – happens in the VECTOR
ii. Asexual cycle aka SCHIZOGONY cycle – happens in Man
Asexual cycle in Man has 2 parts:
i. Exo-erythrocytic cycle – part of the cycle that happens within LIVER/HEPATIC CELL
ii. Erythrocytic cycle – part of the cycle that happens within RBCs
o How long is the cycle in man (asexual cycle)? the length of the cycle varies according to species
o When Plasmodium parasites infect RBCs they alter/change RBC size. In addition, once they are within
RBCs, they consume hemoglobin so RBC stipplings may be found within infected RBCs.
, P. falciparum P. vivax P. ovale P. malariae P. knowlesi
Asexual cycle /
rupturing of infected 36hrs 48hrs 72hrs 24hrs
RBCs
Type of malaria Malignant tertian Benign Ovale malaria Quartan
malaria / Estivo tertian malaria
autumnal malaria malaria
Effect to RBC size No change in rbc Enlarged Enlarged RBC RBC reduced in
size RBC size
Stipplings are called Maurer’s dots Schuffer’s James dots Ziemann’s dots
granules
STAGES SEEN IN THE Only Ring and
BLOOD Gametocytes may All diagnostic stages
be found in the
blood
GAMETOCYTE Crescent/sausage or Round to oval shaped
banana shaped
RING FORM Aplique / accole Amoeboid Band form
TROPHOZOITE Forms
# OF MEROZOITES 6-12 average of 8-
PER INFECTED RBC 8-36 12-24 8, and arranged 10.
around a central Arranged in
block of pigment “rosette” or
“daisy” formation
Note: part of the asexual cycle in man is the RUPTURING of INFECTED RBC, and in the case of P. falciparum as
example, rupturing of RBC happens every 36 hrs. In P. vivax rupturing happens every 48 hrs.etc)
The primary mode of transmission is thru BITES/skin inoculation, and if Malaria is acquired thru bites BOTH exo-
erythrocytic and erythrocytic cycle happens in man. But if the mode of transmission is thru Blood transfusion or
transplacental, there is NO exo-erythrocytic cycle, in man it is only erythrocytic cycle
“Padaliin natin… pag kinagat ka ng infected Female anopheles, una syang pupunta sa liver/hepatic cell, part
ng life cycle ang pag rupture din ng infected liver cell, matapos mag rupture ang infected liver cell, ang next
naman na e-infect ay RBC.” – Dr. light
o Asexual/Schizogony cycle happens in Man (initially within liver cell, then within RBCs)
o Sexual/Sporogony cycle happens in the vector
o Infective stage of Plasmodium spp to Man: SPOROZOITES (given by vector to man)
o Infective stage of Plasmodium to Vector: Gametocyte (acquired by vector from an infected host)
Plasmodium species are INTRAERYTHROCYTIC parasites (they infect RBCs)
Plasmodium falciparum – infects RBCs of all ages (young & mature RBCs)
Plasmodium vivax and Plasmodium ovale – infect young/Immature/juvenile RBCs example of
which are the Reticulocytes
Plasmodium malariae – infects Mature/older RBCs
o All species can cause MALARIA
o Paroxysm is the characteristic /unique symptom of malaria characterized by chills fever and sweating.
This is the symptom regardless of malaria type.
