Cholera is a serious public health problem worldwide. Recently, unprecedented outbreaks have been seen in many countries including Zimbabwe, Haiti, Pakistan, Nepal, Guinea, Cuba, Congo, and Sierra Leone. These cholera outbreaks cause undue suffering with high mortality and morbidity figures as well as economic and social disruption. Bangladesh remains endemic for cholera, which peaks biannually with further increases seen during floods and cyclones .It affects all age groups, although the majority of fatal cases occur in children. Therefore, immunization against cholera remains an important public health tool for preventing and controlling the disease .