Due to an editing error, an article about a speech by Dr. Rita Colwell in some editions of the Sunday Sun incorrectly explained how women in Bangladesh can use the fabric of their saris to prevent cholera, which is spread by organisms in water. Four layers of the fabric are used to filter drinking water.
The Sun regrets the errors.
Carrying her young son in her arms, the woman is rushing into a hospital. There, doctors look at his shrunken, wrinkled abdomen. They diagnose him with cholera.
FOR THE RECORD - CORRECTION
Rita R. Colwell showed slides of this boy last night as she warned her fellow scientists that environmental factors are also implicated in the spread of the devastating disease, which is traditionally linked with the man-made problem of raw sewage mixing with drinking water.
Dr. Colwell, who is president of the American Association for the Advancement of Science and of the University of Maryland Biotechnology Institute, delivered a keynote address at the organization's annual meeting, held last week in Baltimore.
Dr. Colwell explained how seasonal outbreaks of cholera are correlated with weather patterns.
When coastal waters warm, the amount of plankton increases, and so do the numbers of microscopic copepods that feed on the plankton.
And, she said, the stomachs of these creatures were found to be teeming with the cholera bacteria.
The bacteria find their way to people because the copepods are a major food source for fish and are in the water people wash in and drink.
Dr. Colwell said these weather changes and other environmental factors can offer insight into the transmission and virulence of many of the infectious diseases that are emerging again as dangers in daily life.
"Because we are living in an age of antibiotics, we have developed a complacency about the unseen world around us," said Dr. Colwell.
"There is no reason why another great plague can't happen again."
Worldwide, infectious and parasitic diseases kill more people than cardiovascular disease, cancer or chronic obstructive pulmonary diseases, according to figures from the U.S. Centers for Disease Control and Prevention.
Some of the diseases that are considered most threatening include malaria, multidrug-resistant pneumococcal disease, E. coli disease, influenza A and hantavirus infections.
Tuberculosis is now the leading killer of adults worldwide, with 30 million adults expected to die from it in the next 10 years.
According to the World Health Organization, about one-third of the world's population has the disease.
Dr. Colwell's message was that society should respect these pathogens -- particularly viruses -- which can easily mutate to match new conditions.
She has found that cholera can enter a dormant stage and survive much longer than was previously thought. But, she emphasized that simple public health interventions can often save people from these diseases.
Her staff is studying whether women in Bangladesh could use the cheap cloth they dress in to protect them from the copepods.
They believe that if women wrap the material -- called saris -- around themselves four times, they can filter out the vast majority of copepods.