Introduction
Malaria is an infectious disease (mosquito-borne) caused by Plasmodium parasites. This parasitic infection in humans occurs mainly due to five parasitic species: Plasmodium vivax, Plasmodium falciparum, Plasmodium ovale, Plasmodium malaria, and Plasmodium knowlesi. Globally around 1.5 to three million people die each year due to malaria, and the greatest threats are posed mostly by Plasmodium falciparum and Plasmodium vivax.
How Is Malaria Transmitted?
Malaria is transmitted from one person to another through the bite of infected female Anopheles mosquitoes. As these parasites affect red blood cells, malaria can also be transmitted through infected blood via,
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The transplacental route (mother to fetus).
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By sharing used needles.
What Are the Symptoms of Malaria?
The approximate incubation period is 12 days for Plasmodium falciparum, 14 days for Plasmodium vivax and Plasmodium ovale, and 30 days for Plasmodium malariae. During that time, people will not develop any symptoms, but the malarial parasite will multiply. Following that, the typical symptoms seen are fever with chills and rigor.
This may also be associated with,
Nonspecific Symptoms:
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Headache.
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Tiredness.
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Pain in the muscles.
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Pain in joints.
Abdominal Symptoms:
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Nausea.
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Vomiting.
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Diarrhea (watery and loose stool).
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Abdominal pain.
Initially, there will be shaking chills for a few hours (cold stage), followed by high fever (hot stage) and marked sweating (sweating stage). The fever is intermittent, which may occur every other day in Plasmodium vivax and Plasmodium ovale infection (tertian malaria). In the case of Plasmodium malariae, fever occurs every third day (quartan malaria). However, Plasmodium falciparum has no specific pattern of fever. The patients may have anemia (lack of enough healthy red blood cells) and mild jaundice (bilirubin build-up in the blood causing yellow skin color) due to the breakdown of red blood cells. There are also chances for spleen enlargement when this occurs, and mild liver enlargement may also be seen.
What Are the Causes and Risk Factors of Malaria?
Malaria occurs with the bite of infected female Anopheles mosquitoes. When it bites, the uninfected humans undergo various stages with the breakdown of red blood cells to transmit malaria. The below flow chart will explain in detail how a mosquito causes malaria.
In the case of Plasmodium vivax and Plasmodium ovale infections, it is said that some sporozoites remain dormant in the liver as hypnozoites for up to a year or more. These hypnozoites can get reactivated later and cause delayed primary infections or relapses. Relapse can also occur if treatment is not given to eradicate hypnozoites.
In the case of Plasmodium falciparum, it invades red blood cells of all ages. In contrast, Plasmodium vivax and Plasmodium ovale invade immature red blood cells, and Plasmodium malariae invades the developing red blood cells (normoblasts). Parasitemia is most severe in Plasmodium falciparum infection, where more than two percent of all red blood cells can be infected. Hence, the breakdown of red blood cells is most severe in Plasmodium falciparum infection.
The red blood cells infected with Plasmodium falciparum get adhered to capillary endothelium, agglutinate with other infected RBCs (red blood cells), and form clusters with uninfected red blood cells. This leads to ischemia (reduced blood flow) and dysfunction of various organs such as the brain, liver, kidney, lungs, and gut.
How Is Malaria Diagnosed?
Early diagnosis is highly essential for recovery from malaria. When there are signs and symptoms, it is better to immediately reach the doctor and get treatment. The World Health Organization (WHO) says it is better to confirm the diagnosis through microscopic laboratory testing to identify the parasite. Alternatively, a rapid diagnostic test can be performed depending on the available facilities.
Malaria cannot be distinguished only by the symptoms available if there is a combination of symptoms. To distinguish, a parasitological test is essential to identify and treat the disease. In malaria-endemic areas, the severity of the disease causes a large proportion of the population to have mild immunity. So, some people will carry the parasite through the bloodstream but may not fall ill.
How Is Malaria Treated?
Treatment of malaria mainly aims to eliminate the Plasmodium parasite from the blood. People without symptoms are treated to reduce the risk of disease transmission. There are several drugs for the treatment of malaria, and they are:
How Can Malaria Be Prevented?
Several ways to prevent malaria are:
1. Vaccination:
Research is ongoing to develop safe vaccines for malaria. One vaccine has already been licensed in Europe but is not licensed in the United States. So, consult a doctor when there are suspected symptoms.
2. Advice for Travelers:
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Check if there is any risk of malaria in the traveling country.
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Seek the doctor’s help for a precautionary prescription to prevent the disease before visiting the country or place.
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Keep antimalarial drugs handy before leaving home or while traveling.
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Before traveling, consider the risks for pregnant women, children, and elderly patients.
3. Things to Carry:
People who travel should carry prevalent tools such as,
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Mosquito nets.
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Insect repellants. Insect repellants available online tend to provide protection for at least four hours.
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Insecticides.
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Appropriate clothing.
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Fogging or spraying pesticides, similar to those used in the household, is used by local health authorities in emergencies.
All these are not harmful to humans, as the concentration of pesticides kills only the mosquitoes and does not pose any risk to humans.
4. Precautions:
Avoid situations that may increase the risk of getting bitten by mosquitoes. Things to remember are:
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Choose an air-conditioned room.
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Do not stay near stagnant waters.
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Wear clothes that cover the whole body.
Up to around six months after traveling, a person may be able to develop symptoms, so it is not advisable to donate blood for some period.
What Are the Complications Associated With Malaria?
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Kidney failure.
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Brain infection.
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Meningitis or inflammation and infection of the spinal cord and brain.
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Liver failure.
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Hemolytic anemia or blood cell destruction.
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Pulmonary edema or respiratory failure due to fuel buildup in the lungs.
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Hemorrhage or spleen rupture causing internal bleeding.
Conclusion:
Malaria is a life-threatening disease that leads to thousands of deaths a year. To avoid this, we should create awareness and educate people properly to eradicate this disease. When immediate and proper treatment is given, the person can recover from malaria. So, reach out to the doctor when any symptoms appear.
