Cholera is an acute diarrheal illness caused by ingesting food or water contaminated with the bacterium Vibrio cholerae. This infection releases a toxin in the small intestine that triggers profuse, watery diarrhea, which can lead to severe dehydration and life-threatening complications if not treated promptly. The disease spreads rapidly in areas with inadequate sanitation and limited access to clean water, making prevention a matter of securing the environment against this fecal-oral transmission route. This article details the essential, actionable steps individuals can take concerning water, food, and personal hygiene to prevent cholera infection.
Securing Water Sources and Treatment
Contaminated water is the primary vehicle for cholera transmission. Ensuring all water used for consumption and personal care is safe is the most direct preventative measure, utilizing treatment methods ranging from simple household techniques to specialized filtration systems designed to eliminate the bacteria.
Boiling is considered the most effective way to purify water, requiring a rolling boil for at least one minute to kill the Vibrio cholerae bacteria. Once boiled, the water must be stored in a clean, covered container to prevent recontamination from hands or the environment. If boiling is not possible, chemical disinfection using chlorine or iodine tablets is an alternative.
When using household bleach, add two drops of unscented bleach per liter of water and wait 30 minutes before drinking. Specialized microbiological filters (0.3 microns or smaller) can physically remove bacteria. Even after filtering, treating the water with a chemical disinfectant provides an added layer of protection. All water used for drinking, brushing teeth, washing produce, and making ice must be safely treated.
Essential Food Safety Protocols
Food becomes a source of infection when washed with contaminated water, handled by infected persons, or harvested from polluted sources. A simple principle for food safety is to “Boil it, cook it, peel it, or forget it.”
Thorough cooking is necessary, especially for seafood like shellfish, which can harbor Vibrio cholerae from brackish water environments. Food must be eaten while it is still hot and steaming, ensuring all parts of the meal have reached a temperature of at least 70°C (158°F). Any cooked food that has cooled runs the risk of recontamination and requires thorough reheating before consumption.
It is important to avoid raw vegetables and fruits that cannot be peeled, such as leafy greens, as they are often washed or prepared with unsafe water. Food from street vendors or establishments where preparation conditions cannot be verified should be approached with caution. Avoiding contact between raw and cooked foods during preparation also prevents cross-contamination from surfaces or utensils.
Personal Hygiene and Sanitation Practices
Maintaining scrupulous personal hygiene, particularly handwashing, forms a barrier against the fecal-oral spread of the bacteria. Hands must be washed frequently with soap and safe water, especially before preparing or eating food, and after using the toilet.
Proper handwashing involves wetting the hands, applying soap, and scrubbing all surfaces—including the backs of the hands, between the fingers, and under the nails—for at least 20 seconds. This duration allows for the friction and soap to effectively remove and kill pathogens. If soap and safe water are unavailable, an alcohol-based hand sanitizer containing at least 60% alcohol can be used as an interim measure.
Safe disposal of human waste is equally important to prevent environmental contamination of water sources. All feces must be contained and disposed of using a latrine or a toilet, rather than defecating near water bodies. For households with a cholera patient, contaminated surfaces should first be cleaned with soap, then disinfected using a solution of one part household bleach to nine parts water. Safe disposal of soiled items, such as diapers or bedding, is also necessary to break the cycle of infection.
Vaccination and Travel Preparedness
Vaccination provides an additional layer of protection, particularly for individuals traveling to high-risk areas or those residing in places experiencing an outbreak. Oral cholera vaccines are available and are typically administered in one or more doses, depending on the specific product.
For travelers, the oral vaccine is often recommended, as it can offer short-term protection and may also guard against other causes of traveler’s diarrhea. While no vaccine offers 100% effectiveness, it significantly reduces the risk of severe disease.
Travelers should still diligently adhere to all water and food safety precautions, even if vaccinated. Carrying essential supplies, such as hand sanitizer and a personal supply of water purification tablets, can help maintain these preventative measures while in areas where water quality is questionable. A traveler’s medical kit should also include oral rehydration salts, as prompt rehydration is the main treatment for cholera should infection occur.