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Name: Ahipa
Country: India
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History Charles Louis Alphonse Laveran Malaria has probably infected humans for over 50,000 years, and may have been a human pathogen for the entire history of our species.[1] Indeed, close relatives of the human malaria parasites remain common in chimpanzees, our own closest relatives.[2] References to the unique periodic fevers of malaria are found throughout recorded history, beginning in 2700 BC in China during the Xia Dynasty.[3] The term malaria originates from Medieval Italian: mala aria — "bad air"; and the disease was formerly called ague or marsh fever due to its association with swamps. Scientific studies on malaria made their first significant advance in 1880, when a French army doctor working in Algeria named Charles Louis Alphonse Laveran observed parasites inside the red blood cells of people suffering from malaria. He therefore proposed that malaria was caused by this protozoan, the first time protozoa were identified as causing disease. For this and later discoveries, he was awarded the 1907 Nobel Prize for Physiology or Medicine. A year later, Carlos Finlay, a Cuban doctor treating patients with yellow fever in Havana, first suggested that mosquitoes were transmitting disease to humans. However, it was Britain's Sir Ronald Ross working in India who finally proved in 1898 that malaria is transmitted by mosquitoes. He did this by showing that certain mosquito species transmit malaria to birds and isolating malaria parasites from the salivary glands of mosquitoes that had fed on infected birds. For this work Ross received the 1902 Nobel Prize in Medicine. After resigning from the Indian Medical Service, Ross worked at the newly-established Liverpool School of Tropical Medicine and directed malaria-control efforts in Egypt, Panama, Greece and Mauritius. The findings of Finlay and Ross were later confirmed by a medical board headed by Walter Reed in 1900, and its recommendations implemented by William C. Gorgas in the health measures undertaken during construction of the Panama Canal. This public-health work saved the lives of thousands of workers and helped develop the methods used in future public-health campaigns against this disease. In the early twentieth century, before antibiotics, patients with syphilis were intentionally infected with malaria to create a fever. By accurately controlling the fever with quinine, the effects of both syphilis and malaria could be minimised. Although some patients died from malaria, this was preferable than the almost-certain death from syphilis. Although the blood stage and mosquito stages of the malaria life cycle were established in the 19th and early 20th centuries, it was not until the 1980s that the liver stage of the parasite was observed. The discovery of this latent form of the parasite finally explained why people could appear to be cured of malaria but still relapse years after the parasite had disappeared from their bloodstreams. Distribution and impact Areas of the world where malaria is endemic (coloured blue). Malaria causes about 350–500 million infections in humans and approximately one to three million deaths annually this represents at least one death every 30 seconds. The vast majority of cases occur in children under the age of 5 years; pregnant women are also especially vulnerable. Despite efforts to reduce transmission and increase treatment, there has been little change in which areas are at risk of this disease since 1992. Indeed, if the prevalence of malaria stays on its present upwards course, the death rate could double in the next twenty years. Precise statistics are unknown because many cases occur in rural areas where people do not have access to hospitals or the means to afford health care. Consequently, the majority of cases are undocumented. Although co-infection with HIV and malaria does cause increased mortality, this is less of a problem than with HIV/tuberculosis co-infection, due to the two diseases usually attacking different age-ranges, with malaria being most common in the young and tuberculosis most common in the old. However, in areas of unstable malaria transmission, HIV does contribute to the incidence of severe malaria in adults during malaria outbreaks. Malaria is presently endemic in a broad band around the equator, in northern South America, South and Southeast Asia, and much of Africa; however, it is in sub-Saharan Africa where 85–90% of malaria fatalities occur. The geographic distribution of malaria within large regions is complex, and malarial and malaria-free areas are often found close to each other. In drier areas, outbreaks of malaria can be predicted with reasonable accuracy by mapping rainfall. Malaria is more common in rural areas than in cities; this is in contrast to dengue fever where urban areas present the greater risk. For example, the cities of the Philippines, Thailand and Sri Lanka are essentially malaria-free, but the disease is present in many rural regions. By contrast, in West Africa, Ghana and Nigeria have malaria throughout the entire country, though the risk is lower in the larger cities. Symptoms Symptoms of malaria include fever, shivering, arthralgia (joint pain), vomiting, anemia caused by hemolysis, hemoglobinuria, and convulsions. There may be the feeling of tingling in the skin, particularly with malaria caused by P. falciparum. The classical symptom of malaria is cyclical fevers, occuring every two days in P. vivax and P. ovale infections, every three days for P. falciparum, and every four for P. malariae. Severe malaria is almost exclusively caused by P. falciparum infection and usually arises 6-14 days after infection. Consequences of severe malaria include coma and death if untreated—young children and pregnant women are especially vulnerable. Splenomegaly (enlarged spleen), severe headache, cerebral ischemia, hepatomegaly (enlarged liver), and hemoglobinuria with renal failure may occur. Renal failure may cause blackwater fever, where hemoglobin from lysed red blood cells leaks into the urine. In the most severe cases of the disease fatality rates can exceed 20%, even with intensive care and treatment. In endemic areas, treatment is often less satisfactory and the overall fatality rate for all cases of malaria can be as high as one in ten. Over the longer term, developmental impairments have been documented in children who have suffered episodes of severe malaria. Causes Malaria parasites Malaria is caused by protozoan parasites of the genus Plasmodium (phylum Apicomplexa). In humans malaria is caused by P. falciparum, P. malariae, P. ovale, and P. vivax. P. falciparum is responsible for about 80% of infections and 90% of deaths. Parasitic Plasmodium species also infect birds, reptiles, monkeys, chimpanzees and rodents.[24] There has been documented human infections with several simian species of malaria, namely P. knowlesi, P. inui, P. cynomolgi[25] and P. simiovale; however these are mostly of limited public health importance. Although avian malaria can kill chickens and turkeys, this disease does not cause serious economic losses to poultry farmers.[26] Mosquito vectors The parasite's primary (definitive) hosts and transmission vectors are female mosquitoes of the Anopheles genus; it is within the mosquito that malaria undergoes the sexual stages of its life cycle, while humans act as intermediate hosts.[27] Only female mosquitoes feed on blood, thus males do not transmit the disease. The females of the Anopheles genus of mosquito prefer to feed at night. They usually start searching for a meal at dusk, and will continue throughout the night until taking a meal. Young mosquitoes first ingest the malaria parasite by feeding on a human carrier. Infected female Anopheles mosquitoes carry Plasmodium sporozoites in their salivary glands. Malaria can also be transmitted by blood transfusions, although this is rare.[28]

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