Geography of infectious diseases (epidemiology geography)

Exploring the evolutionary the spread of many communicable (and invasive) disease, a prominent Russian scientist, academician e. n. Pavlovskiy created the doctrine of natural recordings of so-called vector-borne diseases. Identifying portions of natural foci of the disease to the specific geographical landscape can adequately predict the risk of epidemics. This applies above all to disease, disseminated infection sources — — animals and arthropods disease which "was chosen by" certain landscapes. So, the plague is found in the steppe, desert and semi-desert areas, populated by ground squirrels, Groundhogs, peschanky they and other natural carriers of the plague in nature; tick-borne encephalitis disease common in the forest zone, where live virus vectors of this disease is iksodovye (grazing) mites, etc.
Distribution and epidemiology of major infectious diseases are relatively well understood. In general, the magnitude of their increase from the temperate zone through the Mediterranean to tropical. One of the most popular in the world of serious diseases - malaria. Although about half of the world's population lives in malaria-endemic areas, the degree of "concentration" of the disease is highest in the tropics. In the mid-60s as a result of use of the achievements of modern medicine, pharmacology and chemistry in most of Asia and Latin America, malaria was considered virtually defeated. However, in subsequent years, there broke out not one outbreak of the disease. Much worse than was the case in Africa, where the conduct of anti-malaria activities for various reasons, have always held difficult. From malaria every year still die 7-9 million people. Hopes for the elimination of poverty with the help of drugs and insecticides are not justified, since the malaria drug resistance arose, and at the carrier - mosquito - resistance to insecticides.
In the tropics, the second place for the dissemination takes schistosomiasis - a parasitic invasive disease and its causative agents tested in freshwater mollusks all stages of development, except for one, which they spend in the human body. This disease rarely causes death, but dramatically reduces the efficiency of adults affects the physical and mental development of children.
Not healed remains trypanosomiasis ("sleeping sickness"), caused by a single-celled parasite, which serves as a carrier of the tsetse fly. The main area of ??distribution of this insect, there are several species, is confined to 15-21 ° S. sh. Africa, where there are about 40 states. Over the last two centuries of sleeping sickness killed millions of Africans. If we add that fly causes great damage to agriculture, livestock infected with the disease, it becomes clear why this insect is called the "curse" of Africa.
Today trypanosomiasis in principle curable. However, many patients seek treatment too late, when it struck the central nervous system and the brain processes began braking. We Africans, unlike Europeans who die within 1-2 months, the disease can last for years, even though, as a rule, too, ends in death.
Fight the tsetse fly in Africa started in the beginning of the century, producing, in particular, the mass shooting of sick animals. Then began to use insecticides, and in recent years used a specially designed traps and the sterile insect technique. Certain progress has been made, but before the final solution to the problem is still far.
In the world each year several hundred cases of plague and the complete elimination of the disease early to say, as it exists in nature, the causative agent of more than 200 species of rodents and small predators, suffering the plague as well as people. Carry the infection paratiziruyuschie animal fleas, although there are other ways of transmission. For example, in recent years in the south of the former Soviet Union enterprising businessmen engaged in catching gophers, fur which allows you to earn good. In Russia, the natural foci of plague (b of the known 11) are concentrated in the North Caucasus.
The history of plague epidemics suggests that this disease ("Black Death") always spread much faster in the most populated areas, as it was, for example, in Europe, in the XIV century. Conducted by scientists extrapolated data show that in 1400 in Europe, there were already 40% of the population is less than in 1348 - the year of the beginning of the epidemic. Turned out to be a very serious outbreak of plague in India in 1994
The global spread have other infectious diseases, the most massive of which - an ordinary flu. Only in recent years in some middle-income countries of the East have managed to cope with tuberculosis, where for a long time he was a universal scourge. In the underdeveloped countries in Africa and many were infectious diseases (in particular, onchocerciasis or "river blindness") acquired a mass character.
Mid-90s marked the cholera outbreak that swept nearly 80 countries, including Russia. In our country, cholera - a phenomenon that unfortunately frequent. It first appeared in 1831 in St. Petersburg and took the life of 7 thousand. Persons. Cholera came to us from India through Afghanistan, Khiva and Persia, and then through Orenburg, Tiflis and Astrakhan. Difficult nature of the disease, deaths caused terror and panic broke out cholera riot. Since cholera "visited" Russia regularly. In 1848 in Moscow Province sick 59 thousand., Of which about 30 thousand. Died. The cholera epidemic that raged in the Crimea during the Crimean War of 1853-1856., Not "left" Russia for a decade. Frequent cholera epidemic occurred later.
Epidemic, these have always been longer and more severe, if accounted for the wars and unrest - hence another name for cholera, "the military infection." In all likelihood, it was the collapse of the Soviet Union and the subsequent inter-ethnic conflicts in no small measure contributed to the latest epidemic of the disease in Russia in the mid-90s (after the parade of sovereignties started the "parade of infections").
Direct relevance to the plot also has AIDS, but let's talk about it specifically.