Because of the temperature limitations on its transmission by its mosquito vectors, P. ![]() It remains, however, very common throughout much of the tropics and subtropics. ![]() vivax is still found sporadically in some temperate regions, where in the past it was widely prevalent. falciparum are the most commonly encountered malaria parasites (Table (Table1). malariae has lost whatever predominance it may once have had and P. onward ( 29, 47, 95, 106).ĮData include all three species P. Tertian and quartan fevers are referred to with similar frequency in writings from northern Europe through much of the past millennium and from around the shores of the Mediterranean Sea from about the 5th century B.C. “Tertian” and “quartan” refers to their characteristic feature of an acute febrile episode, or paroxysm, that returns respectively every third ( P. “Benign tertian” fevers were so named because they were not associated with the severe and often fatal manifestations of the “subtertian, malignant” periodic fevers ( P. To the Europeans, these have been known and characterized since historically ancient times ( 5, 29, 95, 106) as the “benign tertian” ( P. The two which almost certainly achieved the widest global distribution are Plasmodium vivax and Plasmodium malariae. Four species of malaria parasite infect humans (Table (Table1). Malaria is due to blood infection by protozoan parasites of the genus Plasmodium, which are transmitted from one human to another by female Anopheles mosquitoes. The following, therefore, is a brief reconstruction of the evolution and history of malaria and its burdens as we may perceive them at the start of the 21st century. Within recent decades, and especially the last, biochemical and molecular genetic technologies to investigate distant events in the evolution and coevolution of malaria parasites and humans have become available. ![]() In the same period, we have witnessed both the achievements of the first globally coordinated health delivery programs and also their problems. It is only within the past half century that we have experienced malaria against a background of human health and health services which are, for the most part, vastly better than in all previous generations. Our present times also offer a unique perspective on this subject. They are informative and revealing, especially because each is a product of the medical and human health context, general outlook, and knowledge base of its time. But, while the picture remains blurred in a number of places, the many faces and features of malaria and its imprint on the human species emerge, usually clearly and unmistakably. Inferences or conclusions may vary from well-founded and widely accepted to tentative or controversial. It is hampered by difficulties of collecting appropriate and reliable data and by problems of their interpretation. It explores how, when, and where malaria parasites, their mosquito vectors, and humans, may have interacted and with what effect on ourselves, their human hosts. Many believe that the LHC, which stretches 250 feet beneath the ground along the border of France and Switzerland, will soon solve the mystery of the so-called God Particle and help explain the big bang.This article is about the nature and impact of malaria it is not a review of scientific research on malaria. Scientists study their wreckage to unlock the secrets of the subatomic universe. Like many daredevils, these super-accelerated particles will meet a violent end, crashing into one another head-on. When completed in 2005, CERN's Large Hadron Collider will send protons and ions from hydrogen nuclei rushing through a 17-mile circular tunnel at speeds of up to 52,200,000 miles per hour. Fastest Particle Accelerator: Large Hadron Collider.įastest Particle Accelerator: Large Hadron ColliderĬall it the ultimate nuclear drag strip. ![]() From there, scientists will finally be able to accurately map and describe deep space.Ĭhristian Richters. Launched in 1977 to delve far into the cosmos, Voyager 1 is two to three years away from reaching "termination shock," a spot where the outward blowing solar winds that dominate the planetary orbits meet inward moving stellar forces. That comes to 1 million miles every 24 hours, a 38,518-mph pace that makes the 1-ton cruiser the fastest man-made object in space. Every 3.8 minutes, NASA's Voyager 1 probe travels the distance between New York and California.
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