Solar purification of drinking water in remote villages (where some forms of water purification are not available) was found to be negatively associated with cholera rates.

# Households using solar: 67
# Households not using solar: 64

# Cases of cholera in solar group: 3 (4%)
# Cases of cholera in non-solar group: 20 (31%)


Archives of Disease in Childhood 2001;85:293-295.

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