What is the least effective method of controlling spread of cholera?

The least effective method of controlling the spread of cholera is relying solely on quarantine measures. While isolating infected individuals can prevent direct transmission, it does not address the underlying issues such as contaminated water sources and poor sanitation, which are the primary drivers of cholera outbreaks. Without comprehensive public health interventions, including access to clean water, sanitation improvements, and education, quarantine alone is insufficient to control the disease's spread.