2. Introductio
n
• Malaria is a mosquito borne-disease
caused by plasmodium, which is
transmitted by the bite of infected female
anopheles mosquito.
• The term malaria originates from Italian word:
mala aria — "bad air"
• The disease is widespread
in tropical and subtropical regions that are present
in a broad band around the equator.[2] This
includes much of Sub-Saharan Africa, Asia, and
Latin America.
The World Health Organization estimates that in
2012, there were 207 million cases of malaria.
3. History
:
• Malaria or the associated disease have
been noted 4000 years ago.
• References to the unique periodic
fevers of malaria are found throughout
recorded history, beginning in 2700 BC
in China.
• Malaria may have contributed to the
decline of the Roman Empire, and was so
pervasive in Rome that it was known as
the "Roman fever".
4. History
:
• Scientific studies on malaria made their first
significant advance in 1880, when Charles Louis
Alphonse Laveran—a French army doctor
working in the military hospital of Constantine in
Algeria—observed parasites inside the red blood
cells of infected people for the first time. For this
and later discoveries, he was awarded the 1907
Nobel Prize for Physiology or Medicine.
• Scottish physician Sir Ronald Ross who proved
that the mosquito was the vector for malaria for
this he was awarded the Nobel prize in 1902.
5. Histor
y
• The first effective treatment for malaria
came from the bark of cinchona tree,
which contains quinine.
7. Epidemiolog
y
• The WHO estimates that in 2010 there were
219 million cases of malaria resulting in
660,000 deaths.
• Others have estimated the number of
cases at between 350 and 550 million for
falciparum
malaria and deaths in 2010 at 1.24 million up
from 1.0
million deaths in 1990.
• The majority of cases (65%) occur in children
under 15 years old.
• About 125 million pregnant women are at risk
of infection each year; in Sub-Saharan Africa,
maternal malaria is associated with up to
200,000 estimated infant deaths yearly.
8. Epidemiolog
y
• P.vivax is the most common cause of
malaria and is found in subtropical and
temperate areas of the world.
• P. vivaxand P.ovale causes relapsing
malaria.
• P.falciparum is found in the tropical region
and causes the most severe and fatal
disease.
• P.ovale is the least common malarial
species and is endemic in Africa.
11. Aetiolog
y
• Malaria parasites belong to the
genus Plasmodium (phylum Apicomplexa).
• In humans, malaria is caused
by P. falciparum, P. malariae, P. ovale, P. vivax and P.
knowle si.
• Among those infected, P. falciparum is the most
common species identified (~75%) followed by P.
vivax (~20%).
• Although P. falciparum traditionally accounts for
the majority of deaths, recent evidence
suggests
that P.vivax malaria is associated with potentially
life- threatening conditions about as often as with a
diagnosis of P. falciparum infection.
• P.vivax proportionally is more common outside of
Africa
14. Lifecycl
e
• The lifecycle of malaria parasite consists of
following phases:
sexual cycle: in female anopheles mosquito,
definitive host.
Asexual cycle: in human, as intermediate host.
• Sporozoites are the sexual form of the parasite.
• When the infected female anopheles mosquito
bites the human then the sporozoites enter the
human along with the saliva of the mosquito.
• Within 30 min they enter the parenchymal cells of
the liver, where, during next 10-14 days, they
undergo pre- erythrocytic stage of development
and multipication.
15. Lifecycl
e:
• Following mitotic replication of its nucleus, the
parasite is termed as schizont.
• At last the parasite rupture the liver cell and merozoites
are released.
• The merozoites from the liver cell then bind to or enter
the red blood cells and further develops into
trophozoites.
• The multipication here results to Erythrocytic schizont.
• Some merozoites of erythrocytic schizony develop into
male and female gametocytes known as
microgamates and macrogamates res.
• They are sexual form and are found in peripheral
blood.
16. Lifecycl
e:
• Some of the sporozoites also, on entering into
the liver cells, do not undergo asexual
multiplication but enter into a resting phase
called hypnozoite.
• The sexual cycle of malarial parasite
actually starts in the human host by the
formation of gametocytes which are
then transferred to mosquito for further
development.
• In the midgut of the mosquito, one
microgametocyte develops into 4 to 8 thread
like filamentous structures named
17. Lifecycl
e:
• From one macrogamate only one microgamate is
formed.
• The fertilization occurs, and the gamate is known as
zygote.
• The zygotes matures into an ookinete and it
further develops into an oocyst.
• An oocyst mature and it increases in size and a
large number of sporozoites develop inside it.
• The oocyst rupture and releases sporozoites in the
body cavity of mosquito.
• The sporozoites are distributed to different organs of
the mosquito and they have a special predilection
for salivary glands.
• The mosquito is now capable of transmitting the
infection to man.
18. Symptoms of
malaria:
Physical findings may
include:
oElevated
temperature
oPerspiration
oWeakness
oEnlarged spleen
oMild jaundice
oEnlargement of liver
oIncreased
respiration rate.
19. Symptoms of
malaria:
• Other symptoms of malaria are:
• Dry (nonproductive) cough.
• Muscle or back pain or both.
• Enlarged spleen.
• In rare cases, malaria can lead to impaired function of the
brain or
spinal cord, seizures, or loss of consciousness.
• Infection with the P. falciparum parasite is usually more
serious and may become life-threatening.
• Symptoms may appear in cycles. The time between
episodes of fever and other symptoms varies with the
specific parasite. Episodes of symptoms may occur:
Every 48 hours if you are infected with P. vivax or P.ovale.
Every 72 hours if you are infected with P. malariae. Other
common symptoms of malaria include:
20. Pathogenesi
s:
• Incubation period: 10-14 days in P.vivax,
P. falciparum and P.ovale but it is 28-30
days in
P. malariae.
• The typical clinical features consists of
febrile paroxysm, anaemia and
spleenomegaly.
26. .
. Examine blood under microscope
(geimsa stain)
chest x-ray: helpful if respiratory symptoms are
present
CT scan: to evaluate evidence of cerebral edema or
hemorrhage
Medical intervention:
27. Polymerase chain react.ion (PCR)
-determine the species of plasmodium
.Dipstick test
- not as effective when parasite levels
are below 100 parasites/mL of blood
Blood examination:
Thick and thin blood film
33. Malaria project in
Nepal:
• The initiation of Malaria control project
was first started in Nepal in 1954 with an
objective to study malaria in Terai belt of
central Nepal.
• Currently malaria control activities are
carried out in 65 districts at risk of
malaria.