"Changes to the environment that are sweeping the planet are bringing about a rise in infectious diseases, the United Nations Environment Programme (Unep) has warned.
Loss of forests; the building of roads and dams; urban growth; the clearing of natural habitats for agriculture; mining; and pollution of coastal waters are promoting conditions under which new and old pathogens can thrive, according to research published today in Unep's Global Environment Outlook Year Book for 2004/2005.
Ailments previously unknown in human beings are appearing, such as the Nipah virus, which until recently was found normally in Asian fruit bats, according to the report. Nipah's emergence in the late 1990s as an often fatal disease in humans has been linked to a combination of forest fires in Sumatra and the clearance of natural forests in Malaysia for palm plantations. In searching for fruit, bats were forced into closer contact with domestic pigs, giving the virus its chance to spread to humans.
Climate change in particular may aggravate the threats of infectious diseases in three ways, the report suggests. First, by increasing the temperatures under which many diseases and their carriers flourish."
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http://news.independent.co.uk/world/environment/story.jsp?story=613488