Malarial parasite, a global issue............

1. MALARI
AL
PARASI
TE
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PREPARED AND PRESENTED
BY
Mr. MAHESH LAMSAL
CENTRAL DEPARTMENT OF
BIOTECHNOLOGY,KIRTIPUR
31st JULY 2015

2. History and background…
• The word Malariais derived
from the Italian word Mal’ aria
which means Bad air.
Malaria occurs commonly in Africa, Asia,
South America, Central America, Southern
Mexico, Caribbean and North America. The most
common occurrence in -Sub-Saharan Africa.
The second place is the South East Asia.
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3. Prevalence and deaths….
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Malarial cases and deaths are reported maximum in African
countries followed by South East Asian countries.

4. Continued….
• Affects >2400 million people
• About 1.5 million to 3 million deaths every year.
• Malaria kills in one year what AIDS kills in 15 years.
• Out of 65 districts, 13 districts have been classified as high risk.
• Risk districts include:
• Ilam, Jhapa, Morang,
• Dhanusha, Mahottari, Kavre and Sindhuli
• Nawalparashi
• Banke and Bardiya,
• Kailali, Kanchanpur and Dadeldhura
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5. Risk districts from malarial parasites in Nepal.
5High prevalence of malaria is mainly found in the Terai Region.

6. Different Parasites:
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7. Continued….
Plasmodium knowlesi
The Fifth Human Malarial Parasite
•a primates malarial parasite commonly found
in Southeast Asia.
Plasmodium falciparum - most severe and life-
threatening one.
Plasmodium vivax- Most common parasite in Nepal
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8. Malarial parasites characteristics…..
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9. Transmissionofparasites:
.
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Usually, people get malaria by being bitten by an infective
female Anopheles mosquito.
When a mosquito bites an infected person, a small amount
of blood is taken in which contains microscopic malaria
parasites i.e. Plasmodium.
About 1 week later, when the mosquito takes its next
blood meal, these parasites mix with the mosquito’s saliva
and are injected into the person being bitten.

10. Continued….
•Intermediate host : human
•Final host : mosquito
•Infective stage : sporozoite
•Infective mode : mosquito bite skin of human
•Parasitic position : liver and red blood cells
•Transmitted stage : gametocytes
• Schizogonic cycle in red cells : 48 hrs/P.v；36-48 hrs/P.f
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11. Sexual and asexual life cycle of Plasmodium vivax ….
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12. Continued……
 Infection begins when sporozoites, the infective stages, are injected by a
mosquito and are carried around the body until they invade liver hepatocytes.
 Where they undergo a phase of asexual multiplication (exoerythrocytic
schizogony) resulting in the production of many uninucleate merozoites.
 These merozoites flood out into the blood and invade red blood cells where
they initiate a second phase of asexual multiplication (erythrocytic
schizogony) resulting in the production of about 8-16 merozoites which
invade new red blood cells.
 This process is repeated almost indefinitely and is responsible for the
disease, malaria.
 As the infection progresses, some young merozoites develop into male and
female gametocytes that circulate in the peripheral blood until they are taken
up by a female anopheles mosquito when it feeds.
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13. Continued……
 Within the mosquito the gametocytes mature into male and female
gametes,
 Male gametes  microgametocyte
 Female gametes  macrogametocyte
 Fertilization occurs and a motile zygote (ookinete) is formed within
the lumen of the mosquito gut, the beginning of a process known as
sporogony.
 The ookinete penetrates the gut wall and becomes a conspicuous
oocyst within which another phase of multiplication occurs resulting in
the formation of sporozoites that migrate to the salivary glands of a
mosquito and are injected when the mosquito feeds on a new host.
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14. Symptoms…..
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15. Parasitological diagnosis:
• Prompt parasitological confirmation by microscopy or
alternatively by RDTs
A. Clinical symptoms and history
B. Microscopic examination of blood.
1. Thin film and Thick(Giemsa's stain)
To master the morphology of parasites and
changes of infected red cells
2. P.f.: Only Ring forms and gametocytes can
be found in blood film.
C. Other methods: Immunologic/Biochemical/Molecular diagnosis.
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16. Treatment
1. Three principles:
• Control of clinical
symptoms
• Eradication of
gametocytes
• Prevent relapse
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17. 2. Medicines
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18. Prevention
Chemoprophylaxis
Chloroquine / pyrimethamine
used for
prophylaxis of malaria
Chemotherapy: 1 week before entry into the endemic area ;
for 4 weeks after returning from the endemic area.
Malaria vaccines
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19. Prevention….
Mosquito control
(1). Reconstruction of environment: eradicate the
breeding places of mosquitoes.
(2). Spray insecticides: DDVP and so on.
(3). Use mosquito nets (dipping in insecticide),
screen, or mosquito repellents to protect the person
from mosquito bites. 17

20. Something more……….
•Why do mosquitoes bite me and not my
friend?
•Do the male or female mosquitoes bite or is it
both?
•How do mosquitoes find a person to bite or
suck blood? 18

21. Take home message that………..
• Malaria has become a today’s global issue.
• Half of the population of the world are at risk.
• Wherever malaria is present, children are in danger.
• A child suffering or recovering from malaria needs plenty of
liquids and foods.
• Malaria is very dangerous for pregnant women.
• In 2014, 97 countries had on-going malaria transmission and
Nepal is no more far from this fact.
• The Ministry of health and population, through its National
Malaria Control Program, has ambitious vision of a malaria-
free Nepal by 2026.
• Be healthy and keep your environment healthy.
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22. References…….
• http://www.malaria.com/overview/malaria-symptoms-causes
• http://www.cdc.gov/dpdx/malaria/dx.html
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Malaria Overview - International Medical Corps
internationalmedicalcorps.org
List of Plasmodium species - Wikipedia, the free
encyclopedia
en.wikipedia.org
CDC - DPDx - Malaria - Diagnostic Findings
www.cdc.gov
Comparison of the Plasmodium Species Which Cause
Human Malaria - Google Search
www.google.com.np
BIOLOGY OF HUMAN MALARIA PLASMODIA INCLUDING PLASMODIUM KNOWLESI |
Antinori | Mediterranean Journal of Hematology and Infectious Diseases
www.mjhid.org

23. THANK YOU……
•MY SPECIAL THANKS GO TO,
MY RESPECTED TEACHERS
AND
MY FELLOW STUDENTS……
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