Factors responsible for globalization pathogens not yet identified with certainty: some put the phenomenon down to "environmental promiscuity" of people, others blame the antibiotic resistance and growing international tourism. Sure it’s just that infectious diseases "exotic", considered a problem until recently ran ¬ ment, became again one of the most serious threats to global public health.
Spreading by: bio terrorism or clinical accident RATE MORTALITY: 30% BALANCE DEAD: 500 million, 2 million / year in the 60 Theoretically, the disease is controlled. Two government laboratories in the United States and Russia but owns “reserve” of the virus . A survey conducted several years ago by British newspaper The Guardian has determined that, although unlikely, virus smallpox could always be recreated or stolen. It was quite easy for journalists from The Guardian to show that anyterrorist has a laboratory and a medical degree can mail-order segments of DNA from devastating virus. Tube arrived by mail. In the vial, a drop of a white gel, an incomplete sequence, modified DNA extracted from smallpox. Price: 33 pounds and eight pence. Product ordered from a lab Britishbiotech , whose specialists do not even realize they have put in an envelope, stamped and they have sent a sample from a pathogen deadly . One study of 10 people infected with this virus could lead to illness of 2.2 million people in just 180 days. Responsible for smallpox viruses ( Poxviridae ) is an ancient virus family, branched in multiple species, only partially known, which, in turn, infect a host animal species, from mollusks to turkeys and camels. And one of the most famous examples that illustrate the ability of microorganisms to change is given just the family Poxviridae: a virus of this type (variation of bovine smallpox virus) became responsible for one of the most terrible plagues of humanity. Once killed, for several centuries, millions of people, smallpox was in turn killed by humans through a vaccination on a planetary scale. Gradually, smallpox vaccination was abandoned, as such, in the coming decades, an increasing number of human population will not have protection from this disease.
West Nile virus
Spread: mosquitoes RATE MORTALITY: 4% BALANCE DEAD: 1086 (U.S.) from the family ofarboviruses and was first isolated in 1937, a province of Uganda . Nobody knows how he came West Nile virus (West Nile) for the first time in the United States, something that occurred in 1999, but since then the disease that causes the “exploded” across the country. (Last year 4,200 cases were recorded, including 177 deaths.) According to a study by a group of researchers from the University of California , in recent years this virus has undergone mutations that make it more aggressive.Cases of human infection with West Nile virus have been reported recently in more countries of the European Union . People are contaminated mainly from the bite of mosquito , although infections were recorded occurred after transfusion of blood and organ transplants. A virus vector mosquito is feeding on the blood of infected birds. Have been identified as potential vectors for at least 26 species of this insect (several species of the genus Culex , as usual domestic mosquito C. pipiens and Aedes albopictus or tiger mosquito). Pathogen multiplies in the insect body and, after two weeks appears in its salivary glands. Now, the mosquito is ready to spread infection: intepand another flying, inoculate them small amounts of saliva, but enough to transmit the virus, which multiplies in the new “host” and the cycle repeats. Also, some cats can attack vector mosquitoes, horses, dogs, squirrels and rabbits. But these animals are considered “definitive host” virus because their bodies fail to proliferate so much that it can infect other mosquitoes. Contamination is always resume cycle through birds and the virus is not transmitted directly from person to person.