( About 11 months after the start of an E...)El Ni?o cycles linked to cholera outbreaks ,,,Health

About 11 months after the start of an El Ni?o event in the equatorial Pacific, hospitals thousands of miles away in Bangladesh can expect a surge of cholera cases, according to the first mathematical model to link climatic cycles with subsequent cholera outbreaks.

Details of the climate-disease model are reported in the latest issue of the journal Science by ecologists at Cornell University and the universities of Barcelona, Maryland and London. Cholera is caused by the pathogenic microorganism Vibrio cholerae , a bacterium that lives among zooplankton in brackish waters and in estuaries where rivers meet the sea, and infects humans through contaminated water.

Researchers previously had proposed a link between cholera outbreaks and distant El Ni?o Southern Oscillation (ENSO) events that were mediated by increased sea-surface temperatures and higher numbers of bacteria-bearing zooplankton. But it took a complex model that could account for all contributing factors while discounting insignificant correlations --as well as month-by-month records of cholera cases -- to prove the link. Data on cholera incidence, which normally can rise and fall twice each year with local influences such as monsoons and seasonal temperature changes, came from a hospital in Bangladesh that had tested all incoming patients for cholera for 18 years, from January 1980 to March 1998. The Ellner model took into consideration recent frequencies of cholera cases, an ENSO index based on sea-surface temperatures in the Pacific and seasonal variation in local climates. Peaks in cholera incidence at the Bangladesh hospital were found to occur every 3.7 years -- exactly the same frequency as of ENSO events between 1980 and 1998. But the cholera outbreaks and ENSO events did not precisely coincide: The scientists found an 11-month time lag from the start of an ENSO event near the equator and a peak in cholera incidence. A separate analysis o
'"/>




Page: 1 2
Related medicine news :

1. Regular exercise linked to extended menstrual cycles
2. Sleep cycles may be related to metabolism
3. Motorcycles Cause Greater Pollution
4. Cancers of Colon & Rectum linked to Cigarette Smoking
5. Gene linked to early puberty in girls
6. Maternal alcohol consumption linked to behavioral problems in children
7. Gene HPA-2 Met linked to cardiac arrest
8. Early puberty linked to nutrition
9. Alcohol linked to brain activity
10. Cement injections linked to osteoporosis
11. Asthma linked to obesity