You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is You have given ViPS vaccine to a person. How often will you ask him to take booster doses? and explain in detail?
The injectable typhoid vaccine ViPS is a single dose vaccine which requires booster doses every 3 year. Ty21a vaccine is the oral typhoid vaccine. 3 doses are taken on day 1,3 and 5. It is effective for up to 7 years after last dose. It is recommended in people travelling to endemic areas and during out breaks. Ref: Park, Edition 21, Page - 215