This is a wonderful story of a nasty water born disease and a simple prevention that costs next to nothing.
Cholera is a water borne disease and causes many deaths. In places like Bangladesh the women gather drinking water directly from rivers.
Cholera is a disease that continues to ravage developing countries and reemerges sporadically elsewhere throughout the world. According to the World Health Organization (WHO), 58 countries have officially reported cholera in 2001, with a total of 184,311 cases and 2,728 deaths (1). However, there were 293,113 cases of cholera worldwide in 1998, with 10,586 deaths. These annual figures of WHO actually represent the tip of the iceberg, because the morbidity and mortality caused by Vibrio cholerae is grossly underreported owing to surveillance difficulties and also for fear of economic and social consequences (2). In fact, several cholera endemic countries, e.g., Bangladesh, are not included in the WHO report. In 1991, after almost 100 years without cholera, outbreaks in 16 Latin American countries resulted in 400,000 reported cases of cholera and >4,000 reported deaths (3).
Reduction of cholera in Bangladeshi villages by simple filtration: Colwell, Et Al.
Cholera is a bacteria. It was discovered that outbreaks of Cholera seem to coincide with phytoplankton blooms. Further research showed that the Cholera bacterium tended to hang out on the mouths and egg cases of Copepods tiny microscopic crustaceans. To simplify, when phytoplankton was in season, Cholera outbreaks occurred because the bacteria was ingested through drinking water that contained the bacteria, and, the bacteria multiplied using the Copepods as a host.
Boiling drinking water is the best way to cleanse it. The problem in countries like Bangladesh is the scarcity of fuel for cooking. Boiling one's water becomes a very expensive luxury for the villagers. Many of the drilled wells in these areas have become contaminated with arsenic. Many villagers died each year from Cholera as a result.
Strangely enough the answer was so simple and elegant. Anwar Huq, an environmental microbiologist at the University of Maryland Biotechnology Institute in Baltimore is also a Bangledeshi. He had seen women using the cloth of an old Sari to filter water in preparing a sugar drink. Huq and a group of scientists discovered something very basic. Although the Cholera bacteria is so small it would pass right through the filter, the fact that the bacteria existed as a parasite on phytoplankton meant that using an old Sari cloth folded four times for filtration was an effective way to filter out the phytoplankton and the by proxy the Cholera!
Several conclusions can be drawn from this study, which was carried out by a highly interdisciplinary team, including sociologists, physicians, field extension agents, microbiologists, epidemiologists, ecologists, statisticians, and environmental scientists. First, significant reduction in cholera was achieved by filtering out zooplankton, namely copepods, and colonial phytoplankton from household water, both by nylon and sari filtration. From the laboratory and field studies, it was found that sari filtration removed all zooplankton, most of the phytoplankton, and all particulates >20 µm. The nylon filter removed the zooplankton, larger in size, and hence, was almost equally effective. Because cholera is dose dependent (20), by reducing the number of V. cholerae cells by filtration, we were able to achieve significant reduction in the number of cholera cases. Severity of the disease in those cases that did occur among the filtration population also appears to have been reduced. This observation will be confirmed in ongoing studies. Nylon material was also effective in filtering out copepods, but sari cloth is much less expensive, very effective, and readily available to all villagers in Bangladesh. Although sari cloth was used in Bangladesh and found to be effective, with even a visual difference in the quality of water being easily discernible, other material may be similarly functional and can be used in other parts of the world, where untreated water is used for domestic purposes and cholera is endemic. Interestingly, during the period of the study, meetings with the community health workers revealed that a large number of mothers using filtration perceived a positive decline in the incidence of diarrhea within their families. Therefore, efforts are currently being made to quantitate this finding. The importance of such a perception by a village mother would be significant in disseminating the message for effective implementation of the recommended procedure, when a filtration program is initiated. Other waterborne diarrheal diseases endemic in the Bangladesh villages are being analyzed to determine whether similar reduction was achieved and those results will be communicated separately.
Since saris have long been used to filter out insects from drinks, all that was left to do was start a PR campaign and teach the village mothers to fold the old clothes enough times to make the filter work. To clean the filter it need only be dried in the sun.
Folding four times, Cholera outbreaks in Bangladesh were reduced by half!
FILTERING DRINKING water from rivers and ponds through a folded piece of cotton cloth could cut disease by half in cholera-plagued countries, a new field study suggests.
Cholera causes acute watery diarrhoea that can lead to severe dehydration and death in infants and the elderly.
Putting water through an old piece of sari, the traditional garment worn by women in India, folded at least four times halved cholera cases
The results were published in the Journal of National Academy of Sciences. Rita Colwell of the University of Maryland, College Park, director of the US National Science Foundation and the team taught villagers how to fold the cloth, rinse it in filtered water and dry it completely in sunlight after use and why this might prevent disease.
The Hindu: Clothes Clean Drinking Water
Isn't it great to see the good we can do for the world when we put our minds to it? Who would have thought so many lives could be saved with such a simple fix, so inexpensively? I'd love to see more news like this from around the globe rather than all the hate and war we are causing in our lust for other people's resources. This story is inspiring. Let's globalise Peace!
Ted