recentpopularlog in

jerryking : genetic_drift   2

What history can teach us about SARS
Apr. 14, 2003 | TIME |By Pete Davies .As scientists race to unravel the mysteries of SARS, one issue high on their agenda will be the likelihood that the new virus is a cross-species transmission in which the virus has mutated from its animal carrier so that it can infect humans, who have no immunity from the alien invader. The most obvious examples of this are HIV and influenza, and the latter disease has disturbing parallels with SARS. The flu virus lives usually in the stomachs of waterfowl, and the two are co-adapted — the birds don't get sick. It is widely believed among virologists, however, that with the domestication of ducks in southern China 2,000-3,000 years ago, flu jumped species.

This region has always had high densities of people living in close proximity to large populations of pigs and chickens. It's not known in which order, but with this ready pool of targets near at hand, flu has transferred from ducks to all three species — and once established, it can swap back and forth between its different new hosts with devastating effect. The virus survives and thrives by constantly mutating — so that just as our immune systems recognize and kill off one strain, a new one emerges against which our defenses don't work. Most are minor adaptations, the product of genetic "drift." Every now and then, however, something more dramatic occurs: a genetic "shift." Also termed "a reassortment event," this is the creation of a wholly new strain with genetic elements taken from viruses found in different species.
China  epidemics  genetic_drift  genetic_shift  viruses  flu_outbreaks  SARS  proximity  zoonosis  zoonotic  genes  HIV  influenza 
may 2012 by jerryking
The Age of Pandemics - WSJ.com
MAY 2, 2009 | Wall Street Journal | By LARRY BRILLIANT
Modernity--population growth, climate change and increased contact
between humans and animals--is causing more new viruses with pandemic
potential to jump from their traditional animal hosts to humans.
Brilliant outlines what the world needs to do to prepare.

Indeed, to the epidemiological community, the Influenza Pandemic of 2009 is one of the most widely anticipated diseases in history. ....The current pathogen creating the threat is actually a mixture of viral genetic elements from all over the globe that have sorted, shifted, sorted, shifted, drifted and recombined to form this worrisome virus.....Here's the good news: Compared with a few years ago, the world is somewhat better prepared to deal with pandemic influenza. There have been training meetings, table-top exercises, dry runs and preparedness drills at virtually every level of government and civil society. ......Here's the bad news: Today, we remain underprepared for any pandemic or major outbreak, whether it comes from newly emerging infectious diseases, bioterror attack or laboratory accident. We do not have the best general disease surveillance systems or "surge" capacity in our hospitals and health-care facilities......And there is worse news: The 2009 swine flu will not be the last and may not be the worst pandemic that we will face in the coming years. Indeed, we might be entering an Age of Pandemics........In our lifetimes, or our children's lifetimes, we will face a broad array of dangerous emerging 21st-century diseases, man-made or natural, brand-new or old, newly resistant to our current vaccines and antiviral drugs.....Bioterror weapons are cheap and do not need huge labs or government support. They are the poor man's WMD.....
21st._century  bad_news  bioterrorism  disaster_preparedness  disease  disease_surveillance  epidemics  flu_outbreaks  genetic_drift  genetic_shift  infections  influenza  man-made  modernity  pandemics  pathogens  preparation  sorting  surge_capacity  underprepared  viruses  zoonotic 
may 2009 by jerryking

Copy this bookmark:





to read