This life-threatening disease called malaria is spread by the insect vector female Anopheles mosquito that has been infected by the Plasmodium parasite when it feeds on a human. It breeds mainly in a climate which is warm, where there is high humidity and rainy days and is recorded in about 103 countries around the world with an affection rate of 3.3billion people, but sub-Saharan Africa is where 90% of malaria-related deaths occur. Children below the age of five are the most affected.
History of Malaria
The discovery of malaria parasite was on the 6th of November 1880 by a French army surgeon posted in Constantine, Algeria named Charles Louis Alphonse Laveran. He first noticed it in the blood of patients suffering from malaria. Charles Louis Alphonse Laveran was granted a Nobel prize in 1907 for his discovery.
Types of Malaria
Plasmodium falciparum; is held accountable for the majority of malaria mortality worldwide. It is also the most widespread species in sub-Saharan Africa. The rest of the species are not typically as lethal as P. Falciparum.
Plasmodium Vivax is the second most notable species and is widespread in Southeast Asia and Latin America. Plasmodium vivax and Plasmodium Ovale have the added problem of a dormant liver stage, which can resurface even without the bite of a mosquito, which will result in clinical symptoms.
Plasmodium Ovale and Plasmodium malaria do not have a high recorded rate of infection. Plasmodium knowlesi; this particular species infects just primates, with an unclear mode of transmission has led to malaria in humans.
Causes of Malaria
The protozoan parasite of Genus Plasmodium is the causative agent of malaria. The most widespread causative agent of this is Plasmodium falciparum. It is responsible for 85% of malaria cases. The infection starts when an infected female Anopheles mosquito bites a human while feeding, the parasites which are sporozoites are transmitted via the saliva of the mosquito. This further moves in the bloodstream to the liver where it then invades the liver cells, where it undergoes asexual reproduction(tissue schizogony) and then produces lots of merozoites. These go to the red blood cells and infect them and also initiate asexual reproduction (blood schizogony), which produces 8-24 new infective merozoites, the cell then burst, and the infective cycle begins anew.
Also, merozoite can also form a gametocyte; this is the stage which the mosquito can be affected. There are two types of gametocytes which are the males (microgametes) and females (macrogametes). The mosquito ingests them when it sucks infected blood. Inside the mosquito’s midgut, the male and female gametocytes fuse together to form zygotes which then develop into ookinetes. The motile ookinetes pass through the midgut wall and turn into oocysts. The cysts then release sporozoites; these sporozoites migrate into the salivary glands of the mosquito where they get injected into humans while the mosquitos are feeding. The metamorphosis inside a mosquito takes up to two weeks, and after that time the mosquito can transmit the disease.Plasmodium falciparum life cycles cannot be completed at temperatures below 20 °C.
Signs and Symptoms of Malaria
Malaria symptoms can be grouped into two; uncomplicated and severe malaria.
Uncomplicated malaria is identified only when symptoms start to present themselves, but there are absences of signs to show severe infection or vital organs dysfunction. If it is not properly managed, there is a high chance of this form changing to severe malaria or if the host has poor or low immunity or even no immunity at all. Uncomplicated malaria symptoms usually last for about six to ten hours and reappear every second day. There can be longer cycles depending on the strain of the parasite, or mixed symptoms can be present.
As symptoms of malaria bear a resemblance to those of flu, they may be undiagnosed or misdiagnosed in regions where malaria is not so common. In uncomplicated malaria, symptoms have a particular pattern like cold, hot, and sweating stages:
- A cold sensation with a shiver
- High temperature (fever), vomiting, and headaches.
- Seizures may appear if the patient is young.
- The fatigue and sweats experienced will disappear soon after, and the patient will return to normal
In regions where malaria is rampant, many patients already know the symptoms of malaria and do not even bother to go to the doctor, so they treat themselves.
In the case of severe malaria, clinical or laboratory tests show signs of dysfunction of vital organs. Here are the symptoms of severe malaria:
- Fever (increased temperature) with chills.
- Diminished consciousness.
- The patient stays in a prone position.
- Several convulsions.
- Deep breathing and signs of respiratory distress.
- Unusual bleeding and signs of
- Presence of clinical jaundice and evidence of dysfunction of a vital organ.
Severe malaria can be deadly if left untreated.
Malaria: Treatment and Dosages
The primary purpose of the treatment is to eradicate Plasmodium from the bloodstream of the patient. Treatment can also be administered to those without symptoms of being infected so as to decrease the risk of transmission of the disease in the surrounding population. Patients who present with a severe form of malaria or are not able to use oral medications should be administered intravenous infusion.
To treat uncomplicated malaria, WHO recommends artemisinin-based combination therapy (ACT) which is gotten from a plant called Artemisia annua which is also known as the sweet wormwood. This has the potential to decrease the concentration of the Plasmodium parasite in the bloodstream at a very fast rate. The ACT is artemisinin in combination with a partner drug. Since the elimination of the malaria parasite is by artemisinin is done within the first three days, the role of the partner medication is to ensure the removal of the rest of the parasites.
Malaria Prevention
There are various ways of preventing malaria, and they are as follows;
If you are in a region where malaria is prevalent, endeavor to sleep under a mosquito net at all times to avoid the infected mosquito from biting you, cover your skin or use bug spray. The use of insecticides and insect repellants has also proven useful. Most importantly getting rid of any stagnant water in the area as this is a breeding ground for mosquitoes.
Malaria is a dangerous disease that if not treated will lead to a fatal outcome and in some cases death. It is caused by an infected mosquito that bites and transmits the parasite to humans. The symptoms can be misdiagnosed as it is similar to that of flu. Treatment should be done efficiently with ACT oral or intravenously. Ultimately prevention is better than cure.
References
11 Facts About Malaria | DoSomething.org | Volunteer for Social Change. (2018). Dosomething.org. Retrieved 18 April 2018, from https://www.dosomething.org/facts/11-facts-about-malaria
Causes. (2018). Nhs .uk. Retrieved 18 April 2018, from https://www.nhs.uk/conditions/malaria/causes/
CDC – Malaria – About Malaria – FAQs. (2018). Cdc.gov. Retrieved 18 April 2018, from https://www.cdc.gov/malaria/about/faqs.html
Five species | Medicines for Malaria Venture. (2018). Mmv.org. Retrieved 18 April 2018, from https://www.mmv.org/malaria-medicines/five-species
