There is a serious disease that affects between 300 and 500 million people around the world every year. Every thirty seconds, a child dies from it, and over a million people die per year. At least forty percent of the world’s population is at risk of contracting it. That disease is malaria, and it all starts with a single-celled parasite.
Malaria is a parasitic illness caused by a single-celled organism known as Plasmodium. The parasite is carried from host to host by mosquitoes that have fed from an already-infected person. The mosquito, a female Anopheles, thrives in temperate climates like the tropics of Asia, Africa, South America, and Central America.
Malaria symptoms resemble the flu, including shaking chills, high fever, and sweating even as the body’s temperature falls. These symptoms can recur as long as the Plasmodium parasite is alive inside the body.
How is Malaria Contracted?
Malaria is spread through the bite of the female Anopheles mosquito. When it bites, the mosquito sucks in blood to nourish her eggs, and simultaneously deposits saliva into a person’s bloodstream. The saliva contains the single-celled Plasmodium parasites responsible for malaria.
Once Plasmodium enters the bloodstream, they travel to the liver, hiding from the immune system in red blood cells. The parasites mature quickly, multiplying 1000 times between three days and three weeks. The infected cells then rupture and an enormous amount of parasites enter back into the bloodstream, attacking red blood cells to feed on hemoglobin, the part of the blood that carries oxygen. Once this happens, the infection can only end in one of two ways: the infection is defeated through the immune system or medication, or the infected person is overwhelmed and dies.
There are four different species of Plasmodium, and each cause slightly different versions of malaria.
This parasite is the most serious of the four. It affects many more red blood cells and can develop suddenly, causing death within just a few hours if not treated.
Plasmodium vivax is the most common parasite throughout the world. It generally produces mild to moderate symptoms, but can last up to three years with relapses. This form of malaria may become chronic with symptoms that include an enlarged spleen and muscular weakness.
This type of infection can lie dormant in the blood for years and can be asymptomatic, meaning it shows no symptoms. Despite this, it can still be transferred through blood transfusions or mosquito bites. Plasmodium malariae exists mostly in Asia.
The rarest of the four, Plasmodium ovale is found only in West Africa. It is common for someone to have recurring malaria symptoms due to Plasmodium ovale.
In addition, there are several ways to become infected with malaria without receiving a mosquito bite. The first is through a blood transfusion or organ donation from an infected person. Another is through sharing dirty needles during drug use. Finally, a mother can transfer malaria to her unborn child.
Malaria symptoms begin as red blood cells burst and parasites are released. The attacks are recurrent, which means they will repeat more than once in the lifetime of the disease, sometimes as often as every other day. Generally, an attack will progress starting with chills, then a fever, and finally, sweating even as the body temperature falls. Additionally, a person may have headaches, fatigue, aches and pains, vomiting, or nausea. In some cases, malaria can lie dormant for years before presenting symptoms.
Each species of parasite contains slight variations on these symptoms. For instance, a person with P. vivax malaria will feel normal after the sweating stage while a person with P. falciparum will not feel well between attacks and can die without treatment.
P. falciparum is the most deadly malaria that can cause extreme symptoms and complications in a person. Damage to the brain, lungs, and kidneys is possible. Cerebral malaria can develop, leading to high fever, headache, confusion, seizures, and even coma. Additional complications include:
Anemia, or lack of red blood cells, can occur due to damage from parasites
Hypoglycemia, or low blood sugar, which can eventually lead to coma or death
Organ failure – kidneys, liver, or spleen
Fluid can gather in the lungs and cause breathing problems
Diagnosis and Treatment
Because the initial symptoms can be confused with the flu, malaria is sometimes difficult to diagnose. If the person shows symptoms in an area where malaria is prevalent, a doctor knows to test for the disease. Testing involves a blood sample drawn by finger prick. The blood is then examined under a microscope to identify the Plasmodium parasite in the blood.
If Plasmodium is found in the blood, the next step is to determine the species. It is possible to have more than one species in the blood at once. Since it is the most deadly, Plasmodium falciparum demands prompt identification and treatment.
Because early treatment is crucial, care for malaria can start even before diagnosis is confirmed. Once Plasmodium parasites are identified, treatment depends on the species of infecting parasite. Antimalarial medication known as chloroquine is commonly given to people with malaria, but some parasites have become resistant to it. If this is the case, a combination such as quinine with doxycycline can be given as an alternative.
If a patient is experiencing fever and headaches, they may be given aspirin. A hospital stay may also be required so the doctor may monitor the symptoms. Treatment will take effect within one to two days, but it may take weeks to recover fully.
There is currently no vaccine for malaria due to the complex lifecycle of Plasmodium parasites. Instead, the same drugs used to treat malaria are given to prevent it.
For those who live in areas populated with Anopheles mosquitoes, there are precautions that can limit exposure. Prevention starts in the home. Check all screen doors and windows and patch any holes. Treat your home with insecticide and sleep under a mosquito net sprayed with a repellent like permethrin. Mosquitoes are more active at dusk and in the evening, so if you are going to spend any time outside at night, wear long sleeve shirts and pants. You can also spray clothes with permethrin to ward off mosquitoes. Fortunately, these techniques for repelling mosquitoes are relatively effective and inexpensive.