Malaria Flashcards
kills one child in 20
before the age of 5
Malaria
how many people are affected with Malaria every year?
Every year, more than 225 million people become
severely ill with malaria
How many people die from malaria?
800,000 people die each year.
Based on
epidemiological
considerations Alphonse
Laveran concluded what?
“Swamp fevers are due
to a germ”
He discovered Malaria’s life cycle
Alphonse Laveran, 1880
Who is Giovanni Maria Lancisi?
He first described a characteristic black pigmentation of the brain and
spleen in the victims of malaria. Lancisi linked malaria with poisonous
vapours of swamps or stagnant water on the ground
Who is Camillo Golgi?
an Italian neurophysiologist, established that there were at least two forms of the disease, one with tertian periodicity (fever every other day) and one with quartan periodicity (fever every third day). • He prepared high quality micrographs and described the asexual replication of the parasite within the red blood cell • He observed that fever coincided with the rupture and release of merozoites into the blood stream. • He was awarded a Nobel Prize in Medicine for his discoveries in neurophysiology in 1906.
Who is Patrick Manson?
Discovered the transmission of Wucheria
He demonstrated that mosquitos are also involved in the transmission of human malaria
battista Grassi
He identified the major vectors of plasmodium
Battista Grassi
He shows how plasmodium enters an orgnism
Ronald Ross, 1902
The first one to notice parasites in the blood of a patient suffering from malaria
Alphonse Laveran, 1907
Use plasmodium as a treatment for dementia
Junius Wagner-Jauregg. 1927
Discovered the high efficiency of DDT as a contact poison against several arthropods
Paul Muller
Discovered the structure of the nervous system - Malaria.
Camilo Golgi
The parasite spends part of its life cycle inside the red blood cells
Plasmodium
Humans act as intermediate hosts where sexual and asexual forms of the parasite are found.
Plasmodium
The parasite is transmitted by the
bite of the female anopheline
mosquito which acts as the
definitive host
Plasmodium
malignant tertian malaria. Tropics.
Accounts for 50% of all malaria cases. Most pathogenic.
Plasmodium falciparum:
causes benign tertian malaria. Tropics,
subtropics, and some temperate regions. Mostly found in Asia. About 43%
of all malaria cases. Some Africans are refractory to infection because
they lack the red cell receptor that the parasite use to enter.
Plasmodium vivax:
quartan malaria. Subtropics. About 7% of
malaria cases
Plasmodium malariae:
mild tertian malaria. West Africa,
occasionally East Africa. Rare. It was used to treat syphilis
Plasmodium ovale
Invades erythrocytes
Merozoite
invades mosquito salivary gland and liver cells
sporozites
invades mosquito’s gut epithelial cells
ookinete
blood forms what when infected with plasmodium?
merozoites rings trophozoite schizonts "MRTS"
Mosquito forms what when infected with plasmodium?
gametocytes oocyst ookinete sporozoite "GOOS"
Describe Malaria’s life cycle
zygote ookinete oocyst sporozoite mosquito's salivary gland female mosquito injects sporozoites sporozoites invade liver cells sporozoites turn to merozoite schizont ruptures and mezoroites are released into the blood merozoite transform into ring stage trophozoite and some become gametocytes. mosquito bites you and sucks blood with gametocytes. Release eggs infected with plasmodium. CYCLE GOES ON
How many days does it take for sporozoite development in mosquitoes?
10-14 days
made up of thousands of merozoites
schizont
What is a sporozoite?
• 10-15 μm long
• 2 sporozoite surface proteins contain hepatocyte
adhesive domains (CSP circumsporozoite protein and
TRAP thrombospondin related anonymous protein)
• Both proteins bind to glycosoaminoglycans on the surface
of hepatocytes and this binding is important for entry
schionts take how many days to develop?
5-7 days
the parasite undergoes multiple rounds of mitosis to generate nuclei that are assembled into the daughter merozoites. At 48 hours, the infected erythrocyte ruptures to release merozoites.What is this structure?
schizogony
What is the ring stage?
1st 14-16 hours spent as ring stage, or young trophozoite • little to no Hb degradation • only form seen in blood films of P. falciparum
What is a trophozoite?
It forms inside the RBC after 10-18 hours post infection.
It takes up Hg and digest it in a food vacuole
SCHIZOGONY
form of asexual reproduction in which multiple mitoses take place, followed by cytokinesis resulting in multiple daughter cells • multiple mitoses produce 20-24 nuclei • once nuclei & organelles replicated cytokinesis occurs • rupture of RBC membrane releases merozoites
What is gamogony?
Formation of gametocytes
form of asexual reproduction in which multiple mitoses take place, followed by cytokinesis resulting in multiple daughter cells • multiple mitoses produce 20-24 nuclei • once nuclei & organelles replicated cytokinesis occurs • rupture of RBC membrane releases merozoites
Ookinete
These invade the mosquito’s salivary gland
sporozoites
Clinical Symptoms of Malaria
patient’s symptoms and physical examination.
The first symptoms (fever, chills, sweats, headaches, muscle pains, nausea
and vomiting) are not specific.
In severe malaria, clinical findings are more striking (confusion, coma,
neurologic focal signs, severe anemia, respiratory difficulties.
Transmission of Malaria
Female anopheles mosquitoes, and blood transfusion (ei, organ transplant, sharing of needles)
** Transmission is greater in warmer areas
Species of anopheles present in the area influence the intensity of transmission. Might be resistant to insecticides
anopheles mosquitoes
Malaria and sickle cell, Malaria and negative duffy blood group
People with sickle cell are resistant to plasmodium
Prevention of Malaria
use of bed nets, getting rid of stagnant water, cleanliness, insecticides
Malaria and pregnancy
severe maternal anemia
delivery of low infant
fetal loss
Malaria and HIV
HIV-associated immunosuppression contributes to more and worse malaria and its consequences in adults, pregnant women, and children. • Malaria contributes to stimulus of HIV replication and possibly(?) to its consequences: disease progression, transmission in adults, and mother to child transmission. • Co-infection with Malaria and HIV in pregnant women contributes to anemia, low birth weight, and their risk for poor infant survival. • Malarial anemia in children too frequently requires blood transfusion and may still lead to HIV transmission
President’s Malaria Initiative (PMI)
represents an
historic five-year expansion of U.S. Government resources
to fight malaria in the region most affected by the disease.
• $30m (2006) - $500m (2010) in malaria funding to this
Initiative with the goal of reducing malaria-related deaths by
50% in 15 focus countries.
Human Malaria is what?
a blood disease but can causes pathology in a variety of most organs and tissues
What causes malaria?
It is due to the parasite’s development within the RBC
Incubation period
9-14 days
What is cerebral malaria?
is
characterized by multiple brain
hemorrhages (vessel rupture
and bleeding)
What is the pathogenesis of falciparum malaria?
Parasite infected RBC’s become ‘sticky’ and
adhere to endothelial cells
• Unique to falciparum malaria
• This phenomenon takes about 10-12 hours to
develop after parasite invasion
• Under high flow this first results in rolling and
then in attachment.
seems to be
the main culprit for
pathogenesis
Cytoadherance. Infected RBCs will adhere to the endothelium as well as to each other and cause clogging and hemorrhaging
The wonder drug
Chloroquine
a synthetic quinine analog developed by German and American chemists during WWII, was a very potent drug that was cheap to make, stable, and had no serious side effects
Chloroquine
Antifolates as malaria drugs
The synthesis of certain building blocks of DNA requires reduced folate (more specifically the synthesis of dTMP) • No reduced folate -- no DNA • The malaria drug Fansidar uses a drug combination to hit the same target pathway twice • Combinations that are more effective than the sum of their individual activities are called synergistic.
Human Malaria is what?
a blood disease but can causes pathology in a variety of most organs and tissues
Human Malaria is what?
a blood disease but can causes pathology in a variety of most organs and tissues
What causes malaria?
It is due to the parasite’s development within the RBC
What causes malaria?
It is due to the parasite’s development within the RBC
Incubation period
9-14 days
Incubation period
9-14 days
What is cerebral malaria?
is
characterized by multiple brain
hemorrhages (vessel rupture
and bleeding)
What is cerebral malaria?
is
characterized by multiple brain
hemorrhages (vessel rupture
and bleeding)
What is the pathogenesis of falciparum malaria?
Parasite infected RBC’s become ‘sticky’ and
adhere to endothelial cells
• Unique to falciparum malaria
• This phenomenon takes about 10-12 hours to
develop after parasite invasion
• Under high flow this first results in rolling and
then in attachment.
What is the pathogenesis of falciparum malaria?
Parasite infected RBC’s become ‘sticky’ and
adhere to endothelial cells
• Unique to falciparum malaria
• This phenomenon takes about 10-12 hours to
develop after parasite invasion
• Under high flow this first results in rolling and
then in attachment.
seems to be
the main culprit for
pathogenesis
Cytoadherance. Infected RBCs will adhere to the endothelium as well as to each other and cause clogging and hemorrhaging
seems to be
the main culprit for
pathogenesis
Cytoadherance. Infected RBCs will adhere to the endothelium as well as to each other and cause clogging and hemorrhaging
The wonder drug
Chloroquine
The wonder drug
Chloroquine
a synthetic quinine analog developed by German and American chemists during WWII, was a very potent drug that was cheap to make, stable, and had no serious side effects
Chloroquine
a synthetic quinine analog developed by German and American chemists during WWII, was a very potent drug that was cheap to make, stable, and had no serious side effects
Chloroquine
Antifolates as malaria drugs
The synthesis of certain building blocks of DNA requires reduced folate (more specifically the synthesis of dTMP) • No reduced folate -- no DNA • The malaria drug Fansidar uses a drug combination to hit the same target pathway twice • Combinations that are more effective than the sum of their individual activities are called synergistic.
Antifolates as malaria drugs
The synthesis of certain building blocks of DNA requires reduced folate (more specifically the synthesis of dTMP) • No reduced folate -- no DNA • The malaria drug Fansidar uses a drug combination to hit the same target pathway twice • Combinations that are more effective than the sum of their individual activities are called synergistic.
