I am extremely tired of treating myself against malaria but what do I do? Malaria has become a part of our lives in so many countries in Africa, although I heard even that some countries in Africa are malaria-free. The countries are Algeria, Lesotho, Mauritius, and Seychelles, and they have been certified by the world health organization to be malaria-free. Is there a person who lives in this country and can confirm that these countries are malaria-free countries? If you are from any of these countries or have visited them, please share them in the comment section. That said, it is very annoying that I have to treat malaria all the time, and just wish there is something that can be done about it. So in my post today, I will be discussing the Biology, pathology, and recent development of malaria. So let's begin.
Malaria is caused by plasmodium which is carried by mosquitoes. Plasmodium is a parasite which is of the protozoan genus Plasmodium. Malaria is transmitted by the female Anopheles mosquito. In 2021, there were about 247 million cases of malaria worldwide with about 619 000 death which is mainly in children. There are different types of plasmodium that infect man and they include Plasmodium vivax, Plasmodium Falciparum, Plasmodium malariae, and Plasmodium ovale. Plasmodium Vivax and Falciparum are major agents of malaria. When the female anopheles mosquito bites humans, it feeds on their blood and transfers a sporozoite which is an immature form of Plasmodium.
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The sporozoite travels to the liver through the blood and starts to grow in the hepatocytes (the liver cell) and begins to reproduce asexually to form merozoites which are known as schizonts in groups. The liver cells release the merozoites into the bloodstream which occurs between 7 days to 10 days after infection. The merozoites begin to evade the red blood cell and begin to multiply in the red blood cell. In the red blood cell, the merozoite forms into a ring-like shaped immature protozoan called a trophozoite. The trophozoite multiplies asexually in the red blood cell and the red blood cell releases the merozoites into the bloodstream and they continue to evade more red blood cells. When this occurs, the patient starts to experience chills, fever, and sweating which are the typical symptoms of malaria. When it is untreated, the patients could die as the parasite keeps evading the red blood cell and lysing them after they reproduce. In the red blood cell, they can develop into sexual merozoites which reproduce sexually which are the plasmodium gametocyte which then becomes the infected form of the plasmodium that will be taken by the anopheles mosquito and transmitted to another person. So when an uninfected mosquito bites an infected human, they ingest the gametocyte while having their blood meal both male and female which will develop to become gamete in the mosquito which then fuses together to form a zygote when then develops to become an oocyst then a sporozoite which then is transported to the salivary gland of the mosquito where they are readily transmitted to another person.
In the case of treating malaria, there are different antimalaria medicine and different treatments. In the case of severe anemia as a result of the plasmodium lysing the red blood cell, a blood transfusion can be done. Drugs such as Quinolone can be used to treat the disease. The parasite uses the hemoglobin in the red blood cell, which is broken down to heme and protein in the vacuole of the parasite inside the red blood cell. The heme is used as energy and it is converted into hematine which is toxic to the parasite but then converts the hematine to hemozoin which is a non-toxic form. Quinolones which are drugs that include chloroquine, lumefantrine, and amodiaquine target inhibit the conversion of hematin to hemozoin which makes it toxic to the plasmodium but with Plasmodium falciparum, there is a resistance against chloroquine thereby allowing the protozoan to still convert hematin to hemozoin.
Atovaquone is another drug that targets the cytochrome electron transport chain in the mitochondria thereby inhibiting malaria from utilizing the heme to make energy. Side effects of this drug include rash, insomnia, fever, and nausea. There has also been resistance to this drug as a result of a mutation in the cytochrome genes. Drugs such as Sulphonamides inhibit the formation of folate from PABA, Diaminopirimidine which prevents the formation of tetrahydrofolate from folate. Artemisinin is another drug that is activated by ferrous heme which then creates a carbon-centered radical that kills the parasite by damaging the lipid and vacuole membrane of the parasite.
Can we eradicate malaria? It is very complicated that plasmodium is very fast to adapt to any drug created. Since they can resist drugs very fast, do you think continuous production of new drugs is the best option for eliminating the disease? Scientists are also working on gene drives where they make mosquitoes immune to malaria, and pass that immune gene to their offspring. The aim is to release the immune mosquitoes in areas so as to allow for herd immunity among mosquitoes to Plasmodium. While we hope that this becomes a lasting solution, I will advise that people in developing countries use mosquito nets and insecticides when needed to prevent falling ill from malaria.