The world health watchdogs are looking in the wrong places for
the next dangerous epidemics, according to an analysis of global trends in
emerging disease outbreaks over the past few decades. The study
gives a fresh perspective on global disease by tracking the history, from 1940
to 2004, of the emergence and spread of 335 infectious diseases. The extensive
work helps to quantify the effect of well-known risk factors, such as population
density, on the probability of a disease taking hold in a given area.
Although the data haven’t yet been used to map out specific future
hotspots for disease, they do suggest that watchdog groups should invest more in
monitoring regions such as tropical Africa, Latin America and Asia. These areas
have the greatest threats of newly emerging epidemics, say the survey’s authors,
but they have traditionally received the least surveillance. A
globally coordinated strategy is required to spot and stop outbreaks before they
can spread across the world, argues Kate Jones of the Institute of Zoology in
London, one of the researchers behind the new report. "We need
to think more broadly, with a global vision." she says, "Everyone will be
affected by new disease outbreaks. We are all on the same planet--there’s
nowhere to hide." Jones and her colleagues tracked the
infectious diseases over a 64-year span. They included many diseases that have
gone on to cause worldwide misery. The survey paints a picture in which new
diseases arise as a result of dramatic increases in human population density,
international trade and travel, and changes to agricultural practices.
Such changes have caused a dramatic increase in the rate at which new
diseases have emerged since the 1940s, the researchers say. During the 1980s
alone, the worst decade in their date set, almost 100 new pathogens
emerged. That is probably due to the ravages of the most
notorious pathogen(病原体，致病菌) to appear in the 1980s--HIV--the researchers
note. HIV, like 60% of the diseases studies by the researchers,
is a zoonotic(动物传染病的) pathogen-it leapt from animals to humans. Of these
zoonotic diseases, 72% came from wildlife as opposed to domesticated animals,
the researchers found. Recent examples include Nipah virus in Malaysia, and the
infamous SARS outbreak in Guangdong, China, which practically shut down
international travel in Southeast Asia in 2002. According to Kate Jones, what should be done to detect and stop the epidemics before they can spread across the world