Malaria Lifecycle, Symptoms, and Treatment Explained

malaria is an infection that can be caused by a few different types of Plasmodium species which are

single-celled parasites that get spread around by mosquitoes once the Plasmodium gets into the bloodstream it starts to

infect and destroy mainly liver cells and red blood cells which causes a variety of symptoms and sometimes even

death malaria is a serious global health problem that affects millions of people

particularly young children under the age of five pregnant women patients with other

health conditions like HIV and AIDS and travelers who had no prior exposure to malaria

tropical and subtropical regions are hit the hardest together the most affected regions form the malaria belt which is a

broad band around the equator that includes much of Latin America sub-saharan Africa South Asia and

Southeast Asia there are hundreds of types of Plasmodium species but only five cause

malarial disease in humans and those are Plasmodium falciparum plasmodium vivax plasmodium malariae plasmodium ovale and

Plasmodium Noah see plasmodium vivax uses a specific urethra site surface receptor called the duffy

antigen and some individuals particularly those with sickle cell anemia lack this

receptor meaning that Plasmodium vivax can't get into their cells in other words having sickle cell anemia is

genetically related to having relative protection from Plasmodium vivax other diseases like thalassemia and g6pd

deficiency make the parasite infected ureter site and more susceptible to dying from oxidative stress so despite

the obvious downside to having any of these diseases they do offer an upside when it comes to warding off a malaria

infection in fact because malaria has historically circulated in Africa the genes underlying these diseases are

thought to have conferred a natural selection advantage and therefore become more common in the genetic pool

now malaria starts when a Plasmodium infected female Anopheles mosquito hunts for a blood meal in the evening in

through the night like a tiny flying vampire the mosquitoes drawn to carbon dioxide that gets breathed out as well

as bodily smells like foot odor at this point the Plasmodium is in a stage of development called the sporozoite

waiting patiently in the mosquitos salivary gland when the mosquito pierces a person's skin with its long and needle

shaped tusks called the proboscis the tiny worm-like sporozoites spill out of the mosquito saliva and make it into the

bloodstream within minutes the sporozoites reach the liver and mount an attack on the hepatic parenchymal cells

where they start asexual reproduction also known as skinny you

[Music] at this point the Plasmodium species vary a bit over the next one to two

weeks Plasmodium falciparum plasmodium malariae and Plasmodium Knology sporozoites multiply a sexually and

mature into Mara zou lights while host hepatic parenchymal cells die in contrast over the next few months to

years Plasmodium vivax in plasmodium ovale sporozoites enter into a dormant hepatic phase where they're called

Hypno's oh it's hypnotized don't divide instead they snooze for a period of time before entering the process of skits

agony causing a long delay between the initial infection and symptoms from the disease this is called the XO urine

through siddik phase because it happens outside of the earth recite or red blood cell and it's generally asymptomatic

the Marisa lights are then released into the blood and each one binds to a surface receptor and invades a red blood

cell plasmodium ovale and plasmodium falciparum invade red blood cells of all

ages whereas Plasmodium vivax prefers to invade reticulocytes which are young

immature red blood cells I'm plasmodium malariae and plasmodium Nala C preferred to invade older red

blood cells once inside the red blood cell the Marisa white undergoes a sexual

reproduction and a series of transformational changes this phase is known as the urethra siddik phase of

malaria because it happens inside of the red blood cell and generally lasts two to three days in the first stage of the

earth or siddik phase the marrow ZOA it looks like a tiny ring within the red blood cell and is called an early trophy

xuit or a ring form in the second stage the ring form trophies o8 grows and is referred to as a late trophies OA

in the third and final stage the parasite grows some more by digesting hemoglobin and leaves behind Hema xoan

which under a microscope looks a little like a brown faeces smudge on a red blood cell at this point the parasites

called asked its aunt this is the actual replicative phase in which the parasite undergoes mitosis and differentiates

into lots of Marisa whites which can get released into the blood now instead of going into the ear or

acidic phase again some of the marrow is undergo gamete agony which is where they divide and give rise to comida sites

which are little sausage shaped sexual forms that can be either male or female these can be decides to remain inside of

a red blood cell I could get sucked up by another female Anopheles mosquito that might take a blood meal from the

infected person the gamete asides can then reach the mosquitos gut where they mature a bit

more and then fuse together to form a zygote this part of the Plasmodium life cycle is called spur agony and it's

sexual reproduction as opposed to Skiz akane or asexual reproduction that happened in the liver and red blood

cells the zygote then goes on to develop further and it becomes an oaken eat and

then an O assist that ruptures in the mosquitos gut releasing thousands of sporozoites which navigate their way

into the mosquitos salivary gland in order to repeat the cycle all over again now the incubation time which is the

period of time between infection and symptom onset varies depending on the Plasmodium species Plasmodium falciparum

incubates for a few days wears plasmodium malariae incubates for a few weeks the release of tumor necrosis

factor-alpha and other inflammatory cytokines causes fevers that typically happens in paroxysms or short bursts and

correspond to the rupture of the infected red blood cells which happens in waves of reproductive cycles unique

for each Plasmodium species for plasmodium malariae fevers happen every 72 hours and is called a-courtin

fever for Plasmodium vivax in plasmodium ovale fevers happen every 48 hours and these are called tertian fevers

for plasmodium Nala see the fever happens every 24 hours and for Plasmodium falciparum the pattern can

vary sometimes following the pattern of a tertian fever while other times the fevers happen daily earning it the name

malignant tertian fever in addition to fevers the hemolytic anemia which is the destruction of red blood cells also

causes symptoms like extreme fatigue headaches jaundice and splenomegaly most Plasmodium infections have a mild course

of symptoms and are generally regarded as uncomplicated malarial infections out of all the Plasmodium species though

Plasmodium falciparum is known for causing the worst infections most Plasmodium infected red blood cells gets

screened and destroyed by the spleen Plasmodium falciparum though avoid this fate by generating a sticky protein that

coats the surface of the infected red blood cells and these look like knobs or little bumps

this protein causes the red blood cells to clump together and jam up tiny blood vessels a process known as Saito

adherence this literally blocks the flow of blood so that infected cells aren't able to flow into the spleen and it also

blocks blood flow from reaching other vital organs which can wreak havoc on them between hemolytic anemia and

ischemic damage from blocked blood flow organ failure can set in pretty quickly when the brains affected it's termed

cerebral malaria and results in altered Mental Status seizures and coma when the livers affected its term

bilious malaria and it results in diarrhea vomiting jaundice and liver failure other commonly affected organs

include the lungs the kidneys and the spleen which taken together create a sepsis like clinical picture that can

eventually lead to death together all these scenarios are called complicated malaria malaria is usually diagnosed

with a thick blood smear that locates parasites sitting within the red blood cells and a thin blood smear which

directly identifies the Plasmodium species it's also important to know the percentage of red blood cells infected

by a parasite because patients with greater than 5% parasite amia can have worse outcomes some common lab findings

include thrombocytopenia which is a low platelet count elevated lactate dehydrogenase levels due to hemolysis

and a normal chromic normal acidic type of anemia meaning that the red blood cells are few in number but those that

remain are of normal size in color treatment for malaria see divided into the different stages of infection

suppressive treatment or chemo prophylaxis is aimed at killing sporozoites before they infect

hepatocyte s-- so it's usually given to travelers that are headed to a country with endemic malaria therapeutic

treatments aimed at eliminating marisa whites in the urine through siddik phase so it's usually given during an active

infection the exact medication or a group of medications that are used to treat an active infection depends

largely on the severity of the infection the age and pregnancy status of the patient the local malarial resistance

pattern which depends on the geography and the Plasmodium species causing the infection it's also important to not

take the same medication to treat an active infection that was previously used as chemo prophylaxis

comedo Seidel treatments aimed at killing comida sites which prevents spread of disease and thus the creation

of future resistant forms of the parasite lastly radical treatments aimed at

killing hypnocil i'ts in the liver from a Plasmodium vivax and plasmodium ovale infection for the most part cases of

uncomplicated malaria resolved with treatment even after recovery some individuals can

get symptoms after a period of time and this is called recurrent malaria and it's broadly divided into three

underlying causes recrudescence relapse and reinfection recrudescence refers to ineffective treatment that didn't

completely clear the infection a problem common when there are high rates of anti malarial resistance relapse refers to

situations where the blood was cleared of Marisa lights but hypnotize persisted in the liver and then emerged to cause

more problems and reinfection is when an individual was effectively treated but a completely new infection caused a new

bout of malaria a problem common in endemic areas since a single infection doesn't make a person immune malaria

instead there's an acquired ability to tolerate Plasmodium infections which relates to the degree of exposure to a

variety of different strains since malaria is spread by mosquitoes anything that prevents mosquito bites

can help like full body clothing mosquito repellent sleeping in insecticide covered mosquito nets and

using indoor insecticide sprays in addition and all filiz mosquitoes like to lay their eggs in small shallow

collections of fresh water like containers sitting outdoors during the rainy season in tropical countries to

control the mosquito population it's important to empty out these containers and any other stagnant collections of

water alright as a quick recap malaria is a life-threatening mosquito transmitted infection caused by

Plasmodium parasites in which the Plasmodium feeds and grows inside hepatocytes and red blood cells symptoms

are primarily caused by the rupture of red blood cells that usually result in high-grade fever paroxysms that improve

over time but can occasionally cause severe complications in death [Music]

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