WHO report published today.
"In our increasingly interconnected world, new diseases are emerging at an unprecedented rate, often with the ability to cross borders rapidly and spread. Since 1967, at least 39 new pathogens have been identified, including HIV, Ebola haemorrhagic fever, Marburg fever and SARS. Other centuries-old threats, such as pandemic influenza, malaria and tuberculosis, continue to pose a threat to health through a combination of mutation, rising resistance to antimicrobial medicines and weak health systems.
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The report shows how and why diseases are increasingly threatening global public health security. High and rapid mobility of people is one factor. Airlines now carry more than 2 billion passengers a year, enabling people and the diseases that travel with them to pass from one country to another in a matter of hours. The potential health and economic impact was seen in 2003 with SARS, which cost Asian countries an estimated US$ 60 billion of gross expenditure and business losses."
The World Health Organization link to introduction and report:
http://www.who.int/mediacentre/news/releases/2007/pr44/en/index.html