Malaria is caused by a group of the microorganism: plasmodia, very weird microorganisms that consist of just a single cell, they are parasites that completely rely on mosquitoes. Malaria always starts with an insect bite. In its salivary gland, thousand of sporozoites wait until the insect penetrates your skin, immediately after invading you they head for the liver where they quietly enter big cells and hide from the immune system.
For up to a month they stay here in stealth mode consuming the cells alive and changing into their next form: small drop like merozoites, they multiply generating thousand of themselves and then burst out of the cells. So thousands of parasites head into the bloodstream to look for their next victims, Red blood cells, to stay unnoticed, they wrap themselves in the membranes of the cells they killed.
Imagine that! killing someone from the inside and then taking their skin as camouflage, brutal. They now violently attack red blood cells, multiplying inside them until they burst then finding more red blood cells and this cycle repeats over and over. Pieces of dead cells spread lots of toxic waste material, which activates a powerful immune response causing flu-like symptoms, among the symptoms are high fever, sweats and chill, convulsion, headaches and sometimes vomiting and diarrhea.
If malaria breaches the blood-brain barrier it can cause coma, neurological damage, and death. The parasites are already for evacuation now. When another mosquito bites the infected human they get a ride, the cycle can start over. In 2015, the Zika virus, which causes horrible birth defects if it infects pregnant women, spread rapidly into new areas around the globe.
It too is carried by a mosquito. The mosquito is the perfect carrier for human diseases they have been around for at least 200 million years. there are trillions of them and a single one can lay up to 300 eggs at a time. they are practical but today to eradicate and the perfect parasite taxi. Once the Plasmodium gets into the bloodstream of the human body, it starts to directly infect and destroy mainly liver cells and red blood cells, which causes a variety of symptoms and sometimes even death.
Malaria is a very serious health problem all over the world that had affected millions of people, particularly young children under age of 5, pregnant women, patients with other health conditions like HIV and AIDS, and traveler who have had no prior exposure to malaria.
Tropical and subtropical regions are the most suffering area, together with the most malaria-affected regions from the malaria belt, which is broadband 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 malaria, Plasmodium Ovale, and Plasmodium K
Plasmodium vivax make use of a specific erythrocyte surface receptor which is called the Duffy antigen. And some individuals, particularly those with sickle-cell anemia lack this receptor, meaning that Plasmodium vivax cannot get into their cells.
In other words, having sickle cell anemia in human is genetically related to having relative protection against Plasmodium vivax. Other diseases, like thalassemia and G6PD deficiency, make the parasite-infected erythrocyte more susceptible to dying from oxidation stress.
Now, malaria begins when a Plasmodium-infected female Anopheles mosquito hunts for a blood meal in the evening and through the night. Like a tiny flying vampire, the mosquito is drawn to carbon dioxide that gets breathed out as well as bodily smell, like foot odor. At this point, the Plasmodium gets into the stage of development called a sporozoite, waiting with patients in the mosquito’s salivary gland.
When the mosquito bites a person’s skin with its long and needle-shaped tusk, called a proboscis, the tiny, worm-like sporozoites get out of the mosquito‘s saliva and get into the bloodstream. within minutes, the sporozoites reach the liver and attack on hepatic parenchymal cells where they begin asexual reproduction also called as schizogony. At this point, the Plasmodium species very little. Over the next 1-2 weeks, Plasmodium falciparum, Plasmodium malaria, and Plasmodium Knowlesi sporozoites multiply asexually and mature into merozoites, while host hepatic parenchymal cells die.
In contrast, over the next few months, Plasmodium vivax and Plasmodium Ovalesporozoites get into a dormant hepatic phase, where they are called hypnozoites. Hypnozoites don’t divide – instead, they snooze for a period of time before entering the process of schizogony, causing a long delay between the initial infection and symptoms from the disease.
This is called the exoerythrocytic phase because it happens outside of the erythrocyte or red blood cells, and it’s generally asymptomatic. The merozoites are then released into the blood, 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, and Plasmodium malaria and Plasmodium Kowlesi prefer to invade red blood cells which are older.
Once inside the red blood cell, the merozoite undergoes sexual reproduction and a series of transformational changes. this phase is called s the erythrocytic phase of malaria, because it happens inside of the red blood cell and commonly lasts for 2 to 3 days.
Diagnosis of the malaria is usually done with a thick blood smear that locates parasites sitting within the red blood cells and 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% parasitemia can have worse outcomes.
Some of the common lab findings include thrombocytopenia, which is a low platelet count, elevated lactate dehydrogenase levels due to hemolysis, and a normochromic, normocytic type of anemia, meaning that red blood cells are few in number but those that remain are of normal size and color.