What is a key measure against cholera that has been used since 1911?

The correct answer highlights the importance of ensuring the separation of potable water from contaminated sources, which is a fundamental public health strategy to prevent the spread of cholera. Cholera is primarily transmitted through water contaminated with the Vibrio cholerae bacterium, usually due to sewage or fecal matter entering drinking water supplies.

Since cholera outbreaks are closely linked to water quality, measures aimed at maintaining safe drinking water are essential. This includes the implementation of improved sanitation infrastructure and practices to keep drinking water safe from contamination. The practice of separating potable water, which became a focus around 1911, has been crucial in reducing cholera transmission and protecting communities from outbreaks.

While public education campaigns, vaccination programs, and hand sanitation initiatives are certainly valuable components of broader public health efforts against cholera, the specific and direct action of controlling water quality through the separation of potable water has historically proven to be one of the most effective measures in preventing cholera outbreaks. This foundational approach remains relevant even today in areas susceptible to cholera.