When was the first cholera vaccine developed?

Waldemar Haffkine developed an early cholera vaccine in 1892 after extensive laboratory and field research. He tested it in India, where cholera was a major public health threat. His vaccine was among the first to be used on a large scale against a bacterial infection and helped pave the way for modern vaccine trials. Cholera remains a major global disease, but vaccines are now part of control efforts in high-risk areas.