[OANNES Foro] Environmental signatures associated with cholera epidemics

[raul sanchez]

PNAS
November 10, 2008, doi: 10.1073/pnas.0809654105 

Environmental signatures associated with cholera epidemics
Guillaume Constantin de Magnya, Raghu Murtuguddeb, Mathew R. P. Sapianob, Azhar Nizamc, Christopher W. Brownb,d, Antonio J. Busalacchib, Mohammad Yunuse, G. Balakrish Nairf, Ana I. Gilg, Claudio F. Lanatag,h, John Calkinsi, Byomkesh Mannaf, Krishnan Rajendranf, Mihir Kumar Bhattacharyaf, Anwar Huqj, R. Bradley Sackk, and Rita R. Colwella,j,l,1 
-Author Affiliations

aInstitute for Advanced Computer Studies, 
bEarth System Science Interdisciplinary Center, and 
jMaryland Pathogen Research Institute, College of Chemical and Life Sciences, University of Maryland, College Park, MD 20742; 
cDepartment of Biostatistics, Emory University Rollins School of Public Health, Atlanta, GA 30329; 
dSatellite Climate Studies Branch, National Oceanic and Atmospheric Administration, College Park, MD 20742; 
eInternational Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, 1000, Bangladesh; 
fNational Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata 700010, India; 
gInstituto de Investigacion Nutricional, Lima 12, Peru; 
hSchool of Medicine, Universidad Peruana de Ciencias Aplicadas, Lima 12, Peru; 
iEnvironmental Systems Research Institute, Inc., Vienna, VA 22182; and 
kDepartment of International Health and 
lDepartment of Environmental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 
Contributed by Rita R. Colwell, September 26, 2008 (sent for review August 1, 2008)

Abstract
The causative agent of cholera, Vibrio cholerae, has been shown to be autochthonous to riverine, estuarine, and coastal waters along with its host, the copepod, a significant member of the zooplankton community. Temperature, salinity, rainfall and plankton have proven to be important factors in the ecology of V. cholerae, influencing the transmission of the disease in those regions of the world where the human population relies on untreated water as a source of drinking water. In this study, the pattern of cholera outbreaks during 1998–2006 in Kolkata, India, and Matlab, Bangladesh, and the earth observation data were analyzed with the objective of developing a prediction model for cholera. Satellite sensors were used to measure chlorophyll a concentration (CHL) and sea surface temperature (SST). In addition, rainfall data were obtained from both satellite and in situ gauge measurements. From the analyses, a statistically significant relationship
 between the time series for cholera in Kolkata, India, and CHL and rainfall anomalies was determined. A statistically significant one month lag was observed between CHL anomaly and number of cholera cases in Matlab, Bangladesh. From the results of the study, it is concluded that ocean and climate patterns are useful predictors of cholera epidemics, with the dynamics of endemic cholera being related to climate and/or changes in the aquatic ecosystem. When the ecology of V. cholerae is considered in predictive models, a robust early warning system for cholera in endemic regions of the world can be developed for public health planning and decision making. 

ecology epidemiology microbiology remote sensing 
Footnotes
1To whom correspondence should be addressed at: Institute for Advanced Computer Studies, Biomolecular Sciences Building 296, Room 3103, University of Maryland, College Park, MD 20742. E-mail: rcolwell en umiacs.umd.edu 

Saludos cordiales,

Raúl E. Sánchez Scaglioni