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Malaria

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Malaria

Malaria (also called biduoterian fever, blackwater fever, falciparum malaria, plasmodium, Quartan malaria, and tertian malaria) is one of the most infectious and most common diseases in the world. This serious, sometimes-fatal disease is caused by a parasite that is carried by a certain species of mosquito called the Anopheles. It claims more lives every year than any other transmissible disease except tuberculosis. Every year, five hundred million adults and children (around nine percent of the world’s population) contract the disease and of these, one hundred million people die. Children are more susceptible to the disease than adults, and in Africa, where ninety percent of the world’s cases occur and where eighty percent of the cases are treated at home, one in twenty children die of the disease before they reach the age of five. Pregnant women are also more vulnerable to disease and in certain parts of Africa, they are four times as likely to contract the disease and only half as likely to survive it.

The most common sites of malaria-carrying mosquitoes is in tropical and subtropical areas with warm climates. Also, there must be a source of water, such as a lake, ocean, or stream, because this is where the mosquitoes breed. While Africa is the site of most malaria cases, there are a few other countries that account for some of the malaria cases. In fact, in 1990, seventy-five percent of all recorded malaria cases outside Africa were condensed in nine countries, which were India, Brazil, Afghanistan, Sri Lanka, Thailand, Vietnam, Cambodia, Indonesia, and China. There was once a small malaria epidemic in the United States. It occurred mainly in Army families. This was because U.S. troops in other countries were not on the proper medication, contracted the disease, and brought it back to the United States.

Malaria in humans is caused by four species of protozoa, sophisticated one-celled organisms, that can infect red blood cells. These four species are called Plasmodium falciparum, plasmodium vivax, plasmodium malariae, and plasmodium ovale. The worst cases are caused by the Plasmodium falciparum species, which is also the species with the most resistance to drugs. To contract malaria, a mosquito, but not just any mosquito must bite a human. The only type of mosquito that can infect humans with the malaria virus is the Anopheles mosquito. While there are around three hundred eighty species of the Anopheline mosquito, only about sixty are actually able to spread the disease to humans. Also, only female mosquitoes can distribute the disease, as male mosquitoes do not feed on humans.

Mosquitoes pass malaria to humans through their salivary glands. Once the parasites have entered the blood stream, they go to the liver. In the liver they mature and undergo reproduction, forming merozoites. These merozoites enter the blood stream and inject themselves into red blood cells. Once inside the blood cells, they reproduce rapidly and within forty-eight to seventy-two hours, the blood cell bursts, releasing hemoglobin into the blood stream. It is the destruction of these blood cells and the hemoglobin released into the blood stream that actually causes most of the symptoms.

While the most common way malaria is transmitted is from mosquitoes to humans, there are other ways of catching the disease. One way is from mother to her unborn child. When a disease is contracted this way it is said to have been transmitted congenitally. Another way is during blood transfusions. This is why it is important to be tested for diseases such as malaria before you give blood.

Malaria is diagnosed in two different ways. The most exact way is by an examination of the blood. To do this, a doctor would take a drop of blood, stain it, and look at it under a microscope to see if there were any parasites in it. Diagnosing malaria by the symptoms it causes is not as exact as blood examination, but is used a lot in Africa, where most cases are treated at home. In most cases, symptoms appear in ten to forty days. However, they can appear as early as eight days after the bite and as late as one year after the bite. One species of the parasite has been known to remain dormant in the liver for up to four years. Malaria has a lot of symptoms. Some of the most common symptoms of malaria include fever, chills, headache, weakness, vomiting, diarrhea, renal (liver) dysfunction, sweating, muscle pain, and even coma. The symptoms of malaria are some of the same symptoms associated with the flu and that is why so many cases of malaria are improperly diagnosed every year.

When traveling to an area of the world that is high in malaria-carrying mosquitoes, you should take certain precautions. The best way to prevent a case of malaria is to take prescription drugs.

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